Commit Graph

4337 Commits

Author SHA1 Message Date
Kusanagi Kouichi
0e4a459f56 tracing: Remove unnecessary DEBUG_FS dependency
Tracing replaced debugfs with tracefs.

Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20191120104350753.EWCT.12796.ppp.dion.ne.jp@dmta0009.auone-net.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-22 16:19:13 +01:00
Steven Rostedt (VMware)
46f9469247 ftrace: Rename ftrace_graph_stub to ftrace_stub_graph
The ftrace_graph_stub was created and points to ftrace_stub as a way to
assign the functon graph tracer function pointer to a stub function with a
different prototype than what ftrace_stub has and not trigger the C
verifier. The ftrace_graph_stub was created via the linker script
vmlinux.lds.h. Unfortunately, powerpc already uses the name
ftrace_graph_stub for its internal implementation of the function graph
tracer, and even though powerpc would still build, the change via the linker
script broke function tracer on powerpc from working.

By using the name ftrace_stub_graph, which does not exist anywhere else in
the kernel, this should not be a problem.

Link: https://lore.kernel.org/r/1573849732.5937.136.camel@lca.pw

Fixes: b83b43ffc6 ("fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stub")
Reorted-by: Qian Cai <cai@lca.pw>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18 11:42:16 -05:00
Steven Rostedt (VMware)
ea806eb3ea ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization
If a direct ftrace callback is at a location that does not have any other
ftrace helpers attached to it, it is possible to simply just change the
text to call the new caller (if the architecture supports it). But this
requires special architecture code. Currently, modify_ftrace_direct() uses a
trick to add a stub ftrace callback to the location forcing it to call the
ftrace iterator. Then it can change the direct helper to call the new
function in C, and then remove the stub. Removing the stub will have the
location now call the new location that the direct helper is using.

The new helper function does the registering the stub trick, but is a weak
function, allowing an architecture to override it to do something a bit more
direct.

Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-18 11:42:09 -05:00
Steven Rostedt (VMware)
128161f47b ftrace: Add helper find_direct_entry() to consolidate code
Both unregister_ftrace_direct() and modify_ftrace_direct() needs to
normalize the ip passed in to match the rec->ip, as it is acceptable to have
the ip on the ftrace call site but not the start. There are also common
validity checks with the record found by the ip, these should be done for
both unregister_ftrace_direct() and modify_ftrace_direct().

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15 14:25:08 -05:00
Steven Rostedt (VMware)
406acdd32d ftrace: Add another check for match in register_ftrace_direct()
As an instruction pointer passed into register_ftrace_direct() may just
exist on the ftrace call site, but may not be the start of the call site
itself, register_ftrace_direct() still needs to update test if a direct call
exists on the normalized site, as only one direct call is allowed at any one
time.

Fixes: 763e34e74b ("ftrace: Add register_ftrace_direct()")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15 14:24:46 -05:00
Steven Rostedt (VMware)
1c7f9b673d ftrace: Fix accounting bug with direct->count in register_ftrace_direct()
The direct->count wasn't being updated properly, where it only was updated
when the first entry was added, but should be updated every time.

Fixes: 013bf0da04 ("ftrace: Add ftrace_find_direct_func()")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15 14:23:55 -05:00
Artem Bityutskiy
58a74a2925 tracing: Increase SYNTH_FIELDS_MAX for synthetic_events
Increase the maximum allowed count of synthetic event fields from 16 to 32
in order to allow for larger-than-usual events.

Link: http://lkml.kernel.org/r/20191115091730.9192-1-dedekind1@gmail.com

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15 11:30:29 -05:00
Steven Rostedt (VMware)
0567d68091 ftrace: Add modify_ftrace_direct()
Add a new function modify_ftrace_direct() that will allow a user to update
an existing direct caller to a new trampoline, without missing hits due to
unregistering one and then adding another.

Link: https://lore.kernel.org/r/20191109022907.6zzo6orhxpt5n2sv@ast-mbp.dhcp.thefacebook.com

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 22:45:47 -05:00
Steven Rostedt (VMware)
36b3615dc3 tracing: Add missing "inline" in stub function of latency_fsnotify()
The latency_fsnotify() stub when the function is not defined, was missing
the "inline".

Link: https://lore.kernel.org/r/20191115140213.74c5efe7@canb.auug.org.au

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 22:45:47 -05:00
Borislav Petkov
9b4712044d tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help text
There was a stray tab in the help text of the aforementioned config
option which showed like this:

  The "print fmt" of the trace events will show the enum/sizeof names
  instead        of their values. This can cause problems for user space tools
  ...

in menuconfig. Remove it and end a sentence with a fullstop.

No functional changes.

Link: http://lkml.kernel.org/r/20191112174219.10933-1-bp@alien8.de

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:15:12 -05:00
Piotr Maziarz
ef56e047b2 tracing: Use seq_buf_hex_dump() to dump buffers
Without this, buffers can be printed with __print_array macro that has
no formatting options and can be hard to read. The other way is to
mimic formatting capability with multiple calls of trace event with one
call per row which gives performance impact and different timestamp in
each row.

Link: http://lkml.kernel.org/r/1573130738-29390-2-git-send-email-piotrx.maziarz@linux.intel.com

Signed-off-by: Piotr Maziarz <piotrx.maziarz@linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:15:12 -05:00
Masami Hiramatsu
c7411a1a12 tracing/kprobe: Check whether the non-suffixed symbol is notrace
Check whether the non-suffixed symbol is notrace, since suffixed
symbols are generated by the compilers for optimization. Based on
these suffixed symbols, notrace check might not work because
some of them are just a partial code of the original function.
(e.g. cold-cache (unlikely) code is separated from original
 function as FUNCTION.cold.XX)

For example, without this fix,
  # echo p device_add.cold.67 > /sys/kernel/debug/tracing/kprobe_events
  sh: write error: Invalid argument

  # cat /sys/kernel/debug/tracing/error_log
  [  135.491035] trace_kprobe: error: Failed to register probe event
    Command: p device_add.cold.67
               ^
  # dmesg | tail -n 1
  [  135.488599] trace_kprobe: Could not probe notrace function device_add.cold.67

With this,
  # echo p device_add.cold.66 > /sys/kernel/debug/tracing/kprobe_events
  # cat /sys/kernel/debug/kprobes/list
  ffffffff81599de9  k  device_add.cold.66+0x0    [DISABLED]

Actually, kprobe blacklist already did similar thing,
see within_kprobe_blacklist().

Link: http://lkml.kernel.org/r/157233790394.6706.18243942030937189679.stgit@devnote2

Fixes: 45408c4f92 ("tracing: kprobes: Prohibit probing on notrace function")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:15:12 -05:00
Yuming Han
6ee40511cb tracing: use kvcalloc for tgid_map array allocation
Fail to allocate memory for tgid_map, because it requires order-6 page.
detail as:

c3 sh: page allocation failure: order:6,
   mode:0x140c0c0(GFP_KERNEL), nodemask=(null)
c3 sh cpuset=/ mems_allowed=0
c3 CPU: 3 PID: 5632 Comm: sh Tainted: G        W  O    4.14.133+ #10
c3 Hardware name: Generic DT based system
c3 Backtrace:
c3 [<c010bdbc>] (dump_backtrace) from [<c010c08c>](show_stack+0x18/0x1c)
c3 [<c010c074>] (show_stack) from [<c0993c54>](dump_stack+0x84/0xa4)
c3 [<c0993bd0>] (dump_stack) from [<c0229858>](warn_alloc+0xc4/0x19c)
c3 [<c0229798>] (warn_alloc) from [<c022a6e4>](__alloc_pages_nodemask+0xd18/0xf28)
c3 [<c02299cc>] (__alloc_pages_nodemask) from [<c0248344>](kmalloc_order+0x20/0x38)
c3 [<c0248324>] (kmalloc_order) from [<c0248380>](kmalloc_order_trace+0x24/0x108)
c3 [<c024835c>] (kmalloc_order_trace) from [<c01e6078>](set_tracer_flag+0xb0/0x158)
c3 [<c01e5fc8>] (set_tracer_flag) from [<c01e6404>](trace_options_core_write+0x7c/0xcc)
c3 [<c01e6388>] (trace_options_core_write) from [<c0278b1c>](__vfs_write+0x40/0x14c)
c3 [<c0278adc>] (__vfs_write) from [<c0278e10>](vfs_write+0xc4/0x198)
c3 [<c0278d4c>] (vfs_write) from [<c027906c>](SyS_write+0x6c/0xd0)
c3 [<c0279000>] (SyS_write) from [<c01079a0>](ret_fast_syscall+0x0/0x54)

Switch to use kvcalloc to avoid unexpected allocation failures.

Link: http://lkml.kernel.org/r/1571888070-24425-1-git-send-email-chunyan.zhang@unisoc.com

Signed-off-by: Yuming Han <yuming.han@unisoc.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:15:11 -05:00
Srivatsa S. Bhat (VMware)
0c3c86bdc6 tracing/hwlat: Fix a few trivial nits
Update the source file name in the comments, and fix a grammatical
error.

Link: http://lkml.kernel.org/r/157073346821.17189.8946944856026592247.stgit@srivatsa-ubuntu

Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:15:11 -05:00
Andy Shevchenko
80042c8f06 tracing: Use generic type for comparator function
Comparator function type, cmp_func_t, is defined in the types.h,
use it in the code.

Link: http://lkml.kernel.org/r/20191007135656.37734-3-andriy.shevchenko@linux.intel.com

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:15:11 -05:00
Steven Rostedt (VMware)
b83b43ffc6 fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stub
The C compiler is allowing more checks to make sure that function pointers
are assigned to the correct prototype function. Unfortunately, the function
graph tracer uses a special name with its assigned ftrace_graph_return
function pointer that maps to a stub function used by the function tracer
(ftrace_stub). The ftrace_graph_return variable is compared to the
ftrace_stub in some archs to know if the function graph tracer is enabled or
not. This means we can not just simply create a new function stub that
compares it without modifying all the archs.

Instead, have the linker script create a function_graph_stub that maps to
ftrace_stub, and this way we can define the prototype for it to match the
prototype of ftrace_graph_return, and make the compiler checks all happy!

Link: http://lkml.kernel.org/r/20191015090055.789a0aed@gandalf.local.home

Cc: linux-sh@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc:  Rich Felker <dalias@libc.org>
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14 13:13:43 -05:00
Divya Indi
953ae45a0c tracing: Adding NULL checks for trace_array descriptor pointer
As part of commit f45d1225ad ("tracing: Kernel access to Ftrace
instances") we exported certain functions. Here, we are adding some additional
NULL checks to ensure safe usage by users of these APIs.

Link: http://lkml.kernel.org/r/1565805327-579-4-git-send-email-divya.indi@oracle.com

Signed-off-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:29 -05:00
Divya Indi
e585e6469d tracing: Verify if trace array exists before destroying it.
A trace array can be destroyed from userspace or kernel. Verify if the
trace array exists before proceeding to destroy/remove it.

Link: http://lkml.kernel.org/r/1565805327-579-3-git-send-email-divya.indi@oracle.com

Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Divya Indi <divya.indi@oracle.com>
[ Removed unneeded braces ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:29 -05:00
Divya Indi
2d6425af61 tracing: Declare newly exported APIs in include/linux/trace.h
Declare the newly introduced and exported APIs in the header file -
include/linux/trace.h. Moving previous declarations from
kernel/trace/trace.h to include/linux/trace.h.

Link: http://lkml.kernel.org/r/1565805327-579-2-git-send-email-divya.indi@oracle.com

Signed-off-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:29 -05:00
Ben Dooks
6dff4d7dd3 tracing: Make internal ftrace events static
The event_class_ftrace_##call and event_##call do not seem
to be used outside of trace_export.c so make them both static
to avoid a number of sparse warnings:

kernel/trace/trace_entries.h:59:1: warning: symbol 'event_class_ftrace_function' was not declared. Should it be static?
kernel/trace/trace_entries.h:59:1: warning: symbol '__event_function' was not declared. Should it be static?
kernel/trace/trace_entries.h:77:1: warning: symbol 'event_class_ftrace_funcgraph_entry' was not declared. Should it be static?
kernel/trace/trace_entries.h:77:1: warning: symbol '__event_funcgraph_entry' was not declared. Should it be static?
kernel/trace/trace_entries.h:93:1: warning: symbol 'event_class_ftrace_funcgraph_exit' was not declared. Should it be static?
kernel/trace/trace_entries.h:93:1: warning: symbol '__event_funcgraph_exit' was not declared. Should it be static?
kernel/trace/trace_entries.h:129:1: warning: symbol 'event_class_ftrace_context_switch' was not declared. Should it be static?
kernel/trace/trace_entries.h:129:1: warning: symbol '__event_context_switch' was not declared. Should it be static?
kernel/trace/trace_entries.h:149:1: warning: symbol 'event_class_ftrace_wakeup' was not declared. Should it be static?
kernel/trace/trace_entries.h:149:1: warning: symbol '__event_wakeup' was not declared. Should it be static?
kernel/trace/trace_entries.h:171:1: warning: symbol 'event_class_ftrace_kernel_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:171:1: warning: symbol '__event_kernel_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:191:1: warning: symbol 'event_class_ftrace_user_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:191:1: warning: symbol '__event_user_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:214:1: warning: symbol 'event_class_ftrace_bprint' was not declared. Should it be static?
kernel/trace/trace_entries.h:214:1: warning: symbol '__event_bprint' was not declared. Should it be static?
kernel/trace/trace_entries.h:230:1: warning: symbol 'event_class_ftrace_print' was not declared. Should it be static?
kernel/trace/trace_entries.h:230:1: warning: symbol '__event_print' was not declared. Should it be static?
kernel/trace/trace_entries.h:247:1: warning: symbol 'event_class_ftrace_raw_data' was not declared. Should it be static?
kernel/trace/trace_entries.h:247:1: warning: symbol '__event_raw_data' was not declared. Should it be static?
kernel/trace/trace_entries.h:262:1: warning: symbol 'event_class_ftrace_bputs' was not declared. Should it be static?
kernel/trace/trace_entries.h:262:1: warning: symbol '__event_bputs' was not declared. Should it be static?
kernel/trace/trace_entries.h:277:1: warning: symbol 'event_class_ftrace_mmiotrace_rw' was not declared. Should it be static?
kernel/trace/trace_entries.h:277:1: warning: symbol '__event_mmiotrace_rw' was not declared. Should it be static?
kernel/trace/trace_entries.h:298:1: warning: symbol 'event_class_ftrace_mmiotrace_map' was not declared. Should it be static?
kernel/trace/trace_entries.h:298:1: warning: symbol '__event_mmiotrace_map' was not declared. Should it be static?
kernel/trace/trace_entries.h:322:1: warning: symbol 'event_class_ftrace_branch' was not declared. Should it be static?
kernel/trace/trace_entries.h:322:1: warning: symbol '__event_branch' was not declared. Should it be static?
kernel/trace/trace_entries.h:343:1: warning: symbol 'event_class_ftrace_hwlat' was not declared. Should it be static?
kernel/trace/trace_entries.h:343:1: warning: symbol '__event_hwlat' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20191015121012.18824-1-ben.dooks@codethink.co.uk

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:29 -05:00
Sebastian Andrzej Siewior
9c34fc4b7e tracing: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Add additional header output for PREEMPT_RT.
Link: http://lkml.kernel.org/r/20191015191821.11479-34-bigeasy@linutronix.de

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:28 -05:00
Viktor Rosendahl (BMW)
793937236d preemptirq_delay_test: Add the burst feature and a sysfs trigger
This burst feature enables the user to generate a burst of
preempt/irqsoff latencies. This makes it possible to test whether we
are able to detect latencies that systematically occur very close to
each other.

The maximum burst size is 10. We also create 10 identical test
functions, so that we get 10 different backtraces; this is useful
when we want to test whether we can detect all the latencies in a
burst. Otherwise, there would be no easy way of differentiating
between which latency in a burst was captured by the tracer.

In addition, there is a sysfs trigger, so that it's not necessary to
reload the module to repeat the test. The trigger will appear as
/sys/kernel/preemptirq_delay_test/trigger in sysfs.

Link: http://lkml.kernel.org/r/20191008220824.7911-3-viktor.rosendahl@gmail.com

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:28 -05:00
Viktor Rosendahl (BMW)
91edde2e6a ftrace: Implement fs notification for tracing_max_latency
This patch implements the feature that the tracing_max_latency file,
e.g. /sys/kernel/debug/tracing/tracing_max_latency will receive
notifications through the fsnotify framework when a new latency is
available.

One particularly interesting use of this facility is when enabling
threshold tracing, through /sys/kernel/debug/tracing/tracing_thresh,
together with the preempt/irqsoff tracers. This makes it possible to
implement a user space program that can, with equal probability,
obtain traces of latencies that occur immediately after each other in
spite of the fact that the preempt/irqsoff tracers operate in overwrite
mode.

This facility works with the hwlat, preempt/irqsoff, and wakeup
tracers.

The tracers may call the latency_fsnotify() from places such as
__schedule() or do_idle(); this makes it impossible to call
queue_work() directly without risking a deadlock. The same would
happen with a softirq,  kernel thread or tasklet. For this reason we
use the irq_work mechanism to call queue_work().

This patch creates a new workqueue. The reason for doing this is that
I wanted to use the WQ_UNBOUND and WQ_HIGHPRI flags.  My thinking was
that WQ_UNBOUND might help with the latency in some important cases.

If we use:

queue_work(system_highpri_wq, &tr->fsnotify_work);

then the work will (almost) always execute on the same CPU but if we are
unlucky that CPU could be too busy while there could be another CPU in
the system that would be able to process the work soon enough.

queue_work_on() could be used to queue the work on another CPU but it
seems difficult to select the right CPU.

Link: http://lkml.kernel.org/r/20191008220824.7911-2-viktor.rosendahl@gmail.com

Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com>
[ Added max() to have one compare for max latency ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:28 -05:00
Steven Rostedt (VMware)
da537f0aef ftrace: Add information on number of page groups allocated
Looking for ways to shrink the size of the dyn_ftrace structure, knowing the
information about how many pages and the number of groups of those pages, is
useful in working out the best ways to save on memory.

This adds one info print on how many groups of pages were used to allocate
the ftrace dyn_ftrace structures, and also shows the number of pages and
groups in the dyn_ftrace_total_info (which is used for debugging).

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:37:28 -05:00
Steven Rostedt (VMware)
a3ad1a7e39 ftrace/x86: Add a counter to test function_graph with direct
As testing for direct calls from the function graph tracer adds a little
overhead (which is a lot when tracing every function), add a counter that
can be used to test if function_graph tracer needs to test for a direct
caller or not.

It would have been nicer if we could use a static branch, but the static
branch logic fails when used within the function graph tracer trampoline.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:36:49 -05:00
Steven Rostedt (VMware)
013bf0da04 ftrace: Add ftrace_find_direct_func()
As function_graph tracer modifies the return address to insert a trampoline
to trace the return of a function, it must be aware of a direct caller, as
when it gets called, the function's return address may not be at on the
stack where it expects. It may have to see if that return address points to
the a direct caller and adjust if it is.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:36:48 -05:00
Steven Rostedt (VMware)
763e34e74b ftrace: Add register_ftrace_direct()
Add the start of the functionality to allow other trampolines to use the
ftrace mcount/fentry/nop location. This adds two new functions:

 register_ftrace_direct() and unregister_ftrace_direct()

Both take two parameters: the first is the instruction address of where the
mcount/fentry/nop exists, and the second is the trampoline to have that
location called.

This will handle cases where ftrace is already used on that same location,
and will make it still work, where the registered direct called trampoline
will get called after all the registered ftrace callers are handled.

Currently, it will not allow for IP_MODIFY functions to be called at the
same locations, which include some kprobes and live kernel patching.

At this point, no architecture supports this. This is only the start of
implementing the framework.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13 09:36:41 -05:00
Tejun Heo
743210386c cgroup: use cgrp->kn->id as the cgroup ID
cgroup ID is currently allocated using a dedicated per-hierarchy idr
and used internally and exposed through tracepoints and bpf.  This is
confusing because there are tracepoints and other interfaces which use
the cgroupfs ino as IDs.

The preceding changes made kn->id exposed as ino as 64bit ino on
supported archs or ino+gen (low 32bits as ino, high gen).  There's no
reason for cgroup to use different IDs.  The kernfs IDs are unique and
userland can easily discover them and map them back to paths using
standard file operations.

This patch replaces cgroup IDs with kernfs IDs.

* cgroup_id() is added and all cgroup ID users are converted to use it.

* kernfs_node creation is moved to earlier during cgroup init so that
  cgroup_id() is available during init.

* While at it, s/cgroup/cgrp/ in psi helpers for consistency.

* Fallback ID value is changed to 1 to be consistent with root cgroup
  ID.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-12 08:18:04 -08:00
Tejun Heo
40430452fd kernfs: use 64bit inos if ino_t is 64bit
Each kernfs_node is identified with a 64bit ID.  The low 32bit is
exposed as ino and the high gen.  While this already allows using inos
as keys by looking up with wildcard generation number of 0, it's
adding unnecessary complications for 64bit ino archs which can
directly use kernfs_node IDs as inos to uniquely identify each cgroup
instance.

This patch exposes IDs directly as inos on 64bit ino archs.  The
conversion is mostly straight-forward.

* 32bit ino archs behave the same as before.  64bit ino archs now use
  the whole 64bit ID as ino and the generation number is fixed at 1.

* 64bit inos still use the same idr allocator which gurantees that the
  lower 32bits identify the current live instance uniquely and the
  high 32bits are incremented whenever the low bits wrap.  As the
  upper 32bits are no longer used as gen and we don't wanna start ino
  allocation with 33rd bit set, the initial value for highbits
  allocation is changed to 0 on 64bit ino archs.

* blktrace exposes two 32bit numbers - (INO,GEN) pair - to identify
  the issuing cgroup.  Userland builds FILEID_INO32_GEN fids from
  these numbers to look up the cgroups.  To remain compatible with the
  behavior, always output (LOW32,HIGH32) which will be constructed
  back to the original 64bit ID by __kernfs_fh_to_dentry().

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
2019-11-12 08:18:04 -08:00
Tejun Heo
67c0496e87 kernfs: convert kernfs_node->id from union kernfs_node_id to u64
kernfs_node->id is currently a union kernfs_node_id which represents
either a 32bit (ino, gen) pair or u64 value.  I can't see much value
in the usage of the union - all that's needed is a 64bit ID which the
current code is already limited to.  Using a union makes the code
unnecessarily complicated and prevents using 64bit ino without adding
practical benefits.

This patch drops union kernfs_node_id and makes kernfs_node->id a u64.
ino is stored in the lower 32bits and gen upper.  Accessors -
kernfs[_id]_ino() and kernfs[_id]_gen() - are added to retrieve the
ino and gen.  This simplifies ID handling less cumbersome and will
allow using 64bit inos on supported archs.

This patch doesn't make any functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexei Starovoitov <ast@kernel.org>
2019-11-12 08:18:03 -08:00
Frederic Weisbecker
153bedbac2 irq_work: Convert flags to atomic_t
We need to convert flags to atomic_t in order to later fix an ordering
issue on atomic_cmpxchg() failure. This will allow us to use atomic_fetch_or().

Also clarify the nature of those flags.

[ mingo: Converted two more usage site the original patch missed. ]

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191108160858.31665-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-11 09:02:56 +01:00
Steven Rostedt (VMware)
7e16f581a8 ftrace: Separate out functionality from ftrace_location_range()
Create a new function called lookup_rec() from the functionality of
ftrace_location_range(). The difference between lookup_rec() is that it
returns the record that it finds, where as ftrace_location_range() returns
only if it found a match or not.

The lookup_rec() is static, and can be used for new functionality where
ftrace needs to find a record of a specific address.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08 12:26:46 -05:00
Steven Rostedt (VMware)
714641c367 ftrace: Separate out the copying of a ftrace_hash from __ftrace_hash_move()
Most of the functionality of __ftrace_hash_move() can be reused, but not all
of it. That is, __ftrace_hash_move() is used to simply make a new hash from
an existing one, using the same size as the original. Creating a dup_hash(),
where we can specify a new size will be useful when we want to create a hash
with a default size, or simply copy the old one.

Signed-off-by: Steven Rostedt (VMWare) <rostedt@goodmis.org>
2019-11-08 12:25:46 -05:00
Mark Rutland
fbf6c73c5b ftrace: add ftrace_init_nop()
Architectures may need to perform special initialization of ftrace
callsites, and today they do so by special-casing ftrace_make_nop() when
the expected branch address is MCOUNT_ADDR. In some cases (e.g. for
patchable-function-entry), we don't have an mcount-like symbol and don't
want a synthetic MCOUNT_ADDR, but we may need to perform some
initialization of callsites.

To make it possible to separate initialization from runtime
modification, and to handle cases without an mcount-like symbol, this
patch adds an optional ftrace_init_nop() function that architectures can
implement, which does not pass a branch address.

Where an architecture does not provide ftrace_init_nop(), we will fall
back to the existing behaviour of calling ftrace_make_nop() with
MCOUNT_ADDR.

At the same time, ftrace_code_disable() is renamed to
ftrace_nop_initialize() to make it clearer that it is intended to
intialize a callsite into a disabled state, and is not for disabling a
callsite that has been runtime enabled. The kerneldoc description of rec
arguments is updated to cover non-mcount callsites.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Tested-by: Sven Schnelle <svens@stackframe.org>
Tested-by: Torsten Duwe <duwe@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
2019-11-06 14:17:13 +00:00
Miroslav Benes
7162431dcf ftrace: Introduce PERMANENT ftrace_ops flag
Livepatch uses ftrace for redirection to new patched functions. It means
that if ftrace is disabled, all live patched functions are disabled as
well. Toggling global 'ftrace_enabled' sysctl thus affect it directly.
It is not a problem per se, because only administrator can set sysctl
values, but it still may be surprising.

Introduce PERMANENT ftrace_ops flag to amend this. If the
FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be
disabled by disabling ftrace_enabled. Equally, a callback with the flag
set cannot be registered if ftrace_enabled is disabled.

Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz

Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-04 09:33:15 -05:00
David S. Miller
ae8a76fb8b Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-11-02

The following pull-request contains BPF updates for your *net-next* tree.

We've added 30 non-merge commits during the last 7 day(s) which contain
a total of 41 files changed, 1864 insertions(+), 474 deletions(-).

The main changes are:

1) Fix long standing user vs kernel access issue by introducing
   bpf_probe_read_user() and bpf_probe_read_kernel() helpers, from Daniel.

2) Accelerated xskmap lookup, from Björn and Maciej.

3) Support for automatic map pinning in libbpf, from Toke.

4) Cleanup of BTF-enabled raw tracepoints, from Alexei.

5) Various fixes to libbpf and selftests.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-02 15:29:58 -07:00
David S. Miller
d31e95585c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The only slightly tricky merge conflict was the netdevsim because the
mutex locking fix overlapped a lot of driver reload reorganization.

The rest were (relatively) trivial in nature.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-02 13:54:56 -07:00
Daniel Borkmann
6ae08ae3de bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers
The current bpf_probe_read() and bpf_probe_read_str() helpers are broken
in that they assume they can be used for probing memory access for kernel
space addresses /as well as/ user space addresses.

However, plain use of probe_kernel_read() for both cases will attempt to
always access kernel space address space given access is performed under
KERNEL_DS and some archs in-fact have overlapping address spaces where a
kernel pointer and user pointer would have the /same/ address value and
therefore accessing application memory via bpf_probe_read{,_str}() would
read garbage values.

Lets fix BPF side by making use of recently added 3d7081822f ("uaccess:
Add non-pagefault user-space read functions"). Unfortunately, the only way
to fix this status quo is to add dedicated bpf_probe_read_{user,kernel}()
and bpf_probe_read_{user,kernel}_str() helpers. The bpf_probe_read{,_str}()
helpers are kept as-is to retain their current behavior.

The two *_user() variants attempt the access always under USER_DS set, the
two *_kernel() variants will -EFAULT when accessing user memory if the
underlying architecture has non-overlapping address ranges, also avoiding
throwing the kernel warning via 00c42373d3 ("x86-64: add warning for
non-canonical user access address dereferences").

Fixes: a5e8c07059 ("bpf: add bpf_probe_read_str helper")
Fixes: 2541517c32 ("tracing, perf: Implement BPF programs attached to kprobes")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/796ee46e948bc808d54891a1108435f8652c6ca4.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Daniel Borkmann
eb1b668874 bpf: Make use of probe_user_write in probe write helper
Convert the bpf_probe_write_user() helper to probe_user_write() such that
writes are not attempted under KERNEL_DS anymore which is buggy as kernel
and user space pointers can have overlapping addresses. Also, given we have
the access_ok() check inside probe_user_write(), the helper doesn't need
to do it twice.

Fixes: 96ae522795 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/841c461781874c07a0ee404a454c3bc0459eed30.1572649915.git.daniel@iogearbox.net
2019-11-02 12:39:12 -07:00
Alexei Starovoitov
f1b9509c2f bpf: Replace prog_raw_tp+btf_id with prog_tracing
The bpf program type raw_tp together with 'expected_attach_type'
was the most appropriate api to indicate BTF-enabled raw_tp programs.
But during development it became apparent that 'expected_attach_type'
cannot be used and new 'attach_btf_id' field had to be introduced.
Which means that the information is duplicated in two fields where
one of them is ignored.
Clean it up by introducing new program type where both
'expected_attach_type' and 'attach_btf_id' fields have
specific meaning.
In the future 'expected_attach_type' will be extended
with other attach points that have similar semantics to raw_tp.
This patch is replacing BTF-enabled BPF_PROG_TYPE_RAW_TRACEPOINT with
prog_type = BPF_RPOG_TYPE_TRACING
expected_attach_type = BPF_TRACE_RAW_TP
attach_btf_id = btf_id of raw tracepoint inside the kernel
Future patches will add
expected_attach_type = BPF_TRACE_FENTRY or BPF_TRACE_FEXIT
where programs have the same input context and the same helpers,
but different attach points.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191030223212.953010-2-ast@kernel.org
2019-10-31 15:16:59 +01:00
Ingo Molnar
65133033ee Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 12:38:26 +01:00
David S. Miller
5b7fe93db0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-10-27

The following pull-request contains BPF updates for your *net-next* tree.

We've added 52 non-merge commits during the last 11 day(s) which contain
a total of 65 files changed, 2604 insertions(+), 1100 deletions(-).

The main changes are:

 1) Revolutionize BPF tracing by using in-kernel BTF to type check BPF
    assembly code. The work here teaches BPF verifier to recognize
    kfree_skb()'s first argument as 'struct sk_buff *' in tracepoints
    such that verifier allows direct use of bpf_skb_event_output() helper
    used in tc BPF et al (w/o probing memory access) that dumps skb data
    into perf ring buffer. Also add direct loads to probe memory in order
    to speed up/replace bpf_probe_read() calls, from Alexei Starovoitov.

 2) Big batch of changes to improve libbpf and BPF kselftests. Besides
    others: generalization of libbpf's CO-RE relocation support to now
    also include field existence relocations, revamp the BPF kselftest
    Makefile to add test runner concept allowing to exercise various
    ways to build BPF programs, and teach bpf_object__open() and friends
    to automatically derive BPF program type/expected attach type from
    section names to ease their use, from Andrii Nakryiko.

 3) Fix deadlock in stackmap's build-id lookup on rq_lock(), from Song Liu.

 4) Allow to read BTF as raw data from bpftool. Most notable use case
    is to dump /sys/kernel/btf/vmlinux through this, from Jiri Olsa.

 5) Use bpf_redirect_map() helper in libbpf's AF_XDP helper prog which
    manages to improve "rx_drop" performance by ~4%., from Björn Töpel.

 6) Fix to restore the flow dissector after reattach BPF test and also
    fix error handling in bpf_helper_defs.h generation, from Jakub Sitnicki.

 7) Improve verifier's BTF ctx access for use outside of raw_tp, from
    Martin KaFai Lau.

 8) Improve documentation for AF_XDP with new sections and to reflect
    latest features, from Magnus Karlsson.

 9) Add back 'version' section parsing to libbpf for old kernels, from
    John Fastabend.

10) Fix strncat bounds error in libbpf's libbpf_prog_type_by_name(),
    from KP Singh.

11) Turn on -mattr=+alu32 in LLVM by default for BPF kselftests in order
    to improve insn coverage for built BPF progs, from Yonghong Song.

12) Misc minor cleanups and fixes, from various others.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-26 22:57:27 -07:00
Martin KaFai Lau
3820729160 bpf: Prepare btf_ctx_access for non raw_tp use case
This patch makes a few changes to btf_ctx_access() to prepare
it for non raw_tp use case where the attach_btf_id is not
necessary a BTF_KIND_TYPEDEF.

It moves the "btf_trace_" prefix check and typedef-follow logic to a new
function "check_attach_btf_id()" which is called only once during
bpf_check().  btf_ctx_access() only operates on a BTF_KIND_FUNC_PROTO
type now. That should also be more efficient since it is done only
one instead of every-time check_ctx_access() is called.

"check_attach_btf_id()" needs to find the func_proto type from
the attach_btf_id.  It needs to store the result into the
newly added prog->aux->attach_func_proto.  func_proto
btf type has no name, so a proper name should be stored into
"attach_func_name" also.

v2:
- Move the "btf_trace_" check to an earlier verifier phase (Alexei)

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191025001811.1718491-1-kafai@fb.com
2019-10-24 18:41:08 -07:00
Prateek Sood
6b1340cc00 tracing: Fix race in perf_trace_buf initialization
A race condition exists while initialiazing perf_trace_buf from
perf_trace_init() and perf_kprobe_init().

      CPU0                                        CPU1
perf_trace_init()
  mutex_lock(&event_mutex)
    perf_trace_event_init()
      perf_trace_event_reg()
        total_ref_count == 0
	buf = alloc_percpu()
        perf_trace_buf[i] = buf
        tp_event->class->reg() //fails       perf_kprobe_init()
	goto fail                              perf_trace_event_init()
                                                 perf_trace_event_reg()
        fail:
	  total_ref_count == 0

                                                   total_ref_count == 0
                                                   buf = alloc_percpu()
                                                   perf_trace_buf[i] = buf
                                                   tp_event->class->reg()
                                                   total_ref_count++

          free_percpu(perf_trace_buf[i])
          perf_trace_buf[i] = NULL

Any subsequent call to perf_trace_event_reg() will observe total_ref_count > 0,
causing the perf_trace_buf to be always NULL. This can result in perf_trace_buf
getting accessed from perf_trace_buf_alloc() without being initialized. Acquiring
event_mutex in perf_kprobe_init() before calling perf_trace_event_init() should
fix this race.

The race caused the following bug:

 Unable to handle kernel paging request at virtual address 0000003106f2003c
 Mem abort info:
   ESR = 0x96000045
   Exception class = DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
 Data abort info:
   ISV = 0, ISS = 0x00000045
   CM = 0, WnR = 1
 user pgtable: 4k pages, 39-bit VAs, pgdp = ffffffc034b9b000
 [0000003106f2003c] pgd=0000000000000000, pud=0000000000000000
 Internal error: Oops: 96000045 [#1] PREEMPT SMP
 Process syz-executor (pid: 18393, stack limit = 0xffffffc093190000)
 pstate: 80400005 (Nzcv daif +PAN -UAO)
 pc : __memset+0x20/0x1ac
 lr : memset+0x3c/0x50
 sp : ffffffc09319fc50

  __memset+0x20/0x1ac
  perf_trace_buf_alloc+0x140/0x1a0
  perf_trace_sys_enter+0x158/0x310
  syscall_trace_enter+0x348/0x7c0
  el0_svc_common+0x11c/0x368
  el0_svc_handler+0x12c/0x198
  el0_svc+0x8/0xc

Ramdumps showed the following:
  total_ref_count = 3
  perf_trace_buf = (
      0x0 -> NULL,
      0x0 -> NULL,
      0x0 -> NULL,
      0x0 -> NULL)

Link: http://lkml.kernel.org/r/1571120245-4186-1-git-send-email-prsood@codeaurora.org

Cc: stable@vger.kernel.org
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-21 19:38:28 -04:00
YueHaibing
1f5343c0ae bpf: Fix build error without CONFIG_NET
If CONFIG_NET is n, building fails:

kernel/trace/bpf_trace.o: In function `raw_tp_prog_func_proto':
bpf_trace.c:(.text+0x1a34): undefined reference to `bpf_skb_output_proto'

Wrap it into a #ifdef to fix this.

Fixes: a7658e1a41 ("bpf: Check types of arguments passed into helpers")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191018090344.26936-1-yuehaibing@huawei.com
2019-10-18 20:57:07 +02:00
Zhengjun Xing
9fa8c9c647 tracing: Fix "gfp_t" format for synthetic events
In the format of synthetic events, the "gfp_t" is shown as "signed:1",
but in fact the "gfp_t" is "unsigned", should be shown as "signed:0".

The issue can be reproduced by the following commands:

echo 'memlatency u64 lat; unsigned int order; gfp_t gfp_flags; int migratetype' > /sys/kernel/debug/tracing/synthetic_events
cat  /sys/kernel/debug/tracing/events/synthetic/memlatency/format

name: memlatency
ID: 2233
format:
        field:unsigned short common_type;       offset:0;       size:2; signed:0;
        field:unsigned char common_flags;       offset:2;       size:1; signed:0;
        field:unsigned char common_preempt_count;       offset:3;       size:1; signed:0;
        field:int common_pid;   offset:4;       size:4; signed:1;

        field:u64 lat;  offset:8;       size:8; signed:0;
        field:unsigned int order;       offset:16;      size:4; signed:0;
        field:gfp_t gfp_flags;  offset:24;      size:4; signed:1;
        field:int migratetype;  offset:32;      size:4; signed:1;

print fmt: "lat=%llu, order=%u, gfp_flags=%x, migratetype=%d", REC->lat, REC->order, REC->gfp_flags, REC->migratetype

Link: http://lkml.kernel.org/r/20191018012034.6404-1-zhengjun.xing@linux.intel.com

Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-18 14:42:53 -04:00
Kefeng Wang
3da2e1fd46 trace: Use pr_warn instead of pr_warning
As said in commit f2c2cbcc35 ("powerpc: Use pr_warn instead of
pr_warning"), removing pr_warning so all logging messages use a
consistent <prefix>_warn style. Let's do it.

Link: http://lkml.kernel.org/r/20191018031850.48498-26-wangkefeng.wang@huawei.com
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-10-18 15:01:57 +02:00
Joel Fernandes (Google)
da97e18458 perf_event: Add support for LSM and SELinux checks
In current mainline, the degree of access to perf_event_open(2) system
call depends on the perf_event_paranoid sysctl.  This has a number of
limitations:

1. The sysctl is only a single value. Many types of accesses are controlled
   based on the single value thus making the control very limited and
   coarse grained.
2. The sysctl is global, so if the sysctl is changed, then that means
   all processes get access to perf_event_open(2) opening the door to
   security issues.

This patch adds LSM and SELinux access checking which will be used in
Android to access perf_event_open(2) for the purposes of attaching BPF
programs to tracepoints, perf profiling and other operations from
userspace. These operations are intended for production systems.

5 new LSM hooks are added:
1. perf_event_open: This controls access during the perf_event_open(2)
   syscall itself. The hook is called from all the places that the
   perf_event_paranoid sysctl is checked to keep it consistent with the
   systctl. The hook gets passed a 'type' argument which controls CPU,
   kernel and tracepoint accesses (in this context, CPU, kernel and
   tracepoint have the same semantics as the perf_event_paranoid sysctl).
   Additionally, I added an 'open' type which is similar to
   perf_event_paranoid sysctl == 3 patch carried in Android and several other
   distros but was rejected in mainline [1] in 2016.

2. perf_event_alloc: This allocates a new security object for the event
   which stores the current SID within the event. It will be useful when
   the perf event's FD is passed through IPC to another process which may
   try to read the FD. Appropriate security checks will limit access.

3. perf_event_free: Called when the event is closed.

4. perf_event_read: Called from the read(2) and mmap(2) syscalls for the event.

5. perf_event_write: Called from the ioctl(2) syscalls for the event.

[1] https://lwn.net/Articles/696240/

Since Peter had suggest LSM hooks in 2016 [1], I am adding his
Suggested-by tag below.

To use this patch, we set the perf_event_paranoid sysctl to -1 and then
apply selinux checking as appropriate (default deny everything, and then
add policy rules to give access to domains that need it). In the future
we can remove the perf_event_paranoid sysctl altogether.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Co-developed-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: James Morris <jmorris@namei.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: rostedt@goodmis.org
Cc: Yonghong Song <yhs@fb.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: jeffv@google.com
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: primiano@google.com
Cc: Song Liu <songliubraving@fb.com>
Cc: rsavitski@google.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Matthew Garrett <matthewgarrett@google.com>
Link: https://lkml.kernel.org/r/20191014170308.70668-1-joel@joelfernandes.org
2019-10-17 21:31:55 +02:00
Alexei Starovoitov
a7658e1a41 bpf: Check types of arguments passed into helpers
Introduce new helper that reuses existing skb perf_event output
implementation, but can be called from raw_tracepoint programs
that receive 'struct sk_buff *' as tracepoint argument or
can walk other kernel data structures to skb pointer.

In order to do that teach verifier to resolve true C types
of bpf helpers into in-kernel BTF ids.
The type of kernel pointer passed by raw tracepoint into bpf
program will be tracked by the verifier all the way until
it's passed into helper function.
For example:
kfree_skb() kernel function calls trace_kfree_skb(skb, loc);
bpf programs receives that skb pointer and may eventually
pass it into bpf_skb_output() bpf helper which in-kernel is
implemented via bpf_skb_event_output() kernel function.
Its first argument in the kernel is 'struct sk_buff *'.
The verifier makes sure that types match all the way.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-11-ast@kernel.org
2019-10-17 16:44:36 +02:00
Alexei Starovoitov
9e15db6613 bpf: Implement accurate raw_tp context access via BTF
libbpf analyzes bpf C program, searches in-kernel BTF for given type name
and stores it into expected_attach_type.
The kernel verifier expects this btf_id to point to something like:
typedef void (*btf_trace_kfree_skb)(void *, struct sk_buff *skb, void *loc);
which represents signature of raw_tracepoint "kfree_skb".

Then btf_ctx_access() matches ctx+0 access in bpf program with 'skb'
and 'ctx+8' access with 'loc' arguments of "kfree_skb" tracepoint.
In first case it passes btf_id of 'struct sk_buff *' back to the verifier core
and 'void *' in second case.

Then the verifier tracks PTR_TO_BTF_ID as any other pointer type.
Like PTR_TO_SOCKET points to 'struct bpf_sock',
PTR_TO_TCP_SOCK points to 'struct bpf_tcp_sock', and so on.
PTR_TO_BTF_ID points to in-kernel structs.
If 1234 is btf_id of 'struct sk_buff' in vmlinux's BTF
then PTR_TO_BTF_ID#1234 points to one of in kernel skbs.

When PTR_TO_BTF_ID#1234 is dereferenced (like r2 = *(u64 *)r1 + 32)
the btf_struct_access() checks which field of 'struct sk_buff' is
at offset 32. Checks that size of access matches type definition
of the field and continues to track the dereferenced type.
If that field was a pointer to 'struct net_device' the r2's type
will be PTR_TO_BTF_ID#456. Where 456 is btf_id of 'struct net_device'
in vmlinux's BTF.

Such verifier analysis prevents "cheating" in BPF C program.
The program cannot cast arbitrary pointer to 'struct sk_buff *'
and access it. C compiler would allow type cast, of course,
but the verifier will notice type mismatch based on BPF assembly
and in-kernel BTF.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-7-ast@kernel.org
2019-10-17 16:44:35 +02:00
Petr Mladek
d303de1fcf tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
A customer reported the following softlockup:

[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002]  tracing_read_pipe+0x336/0x3c0
[899688.160002]  __vfs_read+0x26/0x140
[899688.160002]  vfs_read+0x87/0x130
[899688.160002]  SyS_read+0x42/0x90
[899688.160002]  do_syscall_64+0x74/0x160

It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.

Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.

The culprit seems to be in the code:

	/* reset all but tr, trace, and overruns */
	memset(&iter->seq, 0,
	       sizeof(struct trace_iterator) -
	       offsetof(struct trace_iterator, seq));

It was added by the commit 53d0aa7730 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:

     struct trace_seq {
	unsigned char		buffer[PAGE_SIZE];
	unsigned int		len;
     };

There was no "size" variable and zeroing was perfectly fine.

The solution is to reinitialize the structure after or without
zeroing.

Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com

Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:49:34 -04:00
Srivatsa S. Bhat (VMware)
fc64e4ad80 tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
max_latency is intended to record the maximum ever observed hardware
latency, which may occur in either part of the loop (inner/outer). So
we need to also consider the outer-loop sample when updating
max_latency.

Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu

Fixes: e7c15cd8a1 ("tracing: Added hardware latency tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:49:33 -04:00
Srivatsa S. Bhat (VMware)
98dc19c114 tracing/hwlat: Report total time spent in all NMIs during the sample
nmi_total_ts is supposed to record the total time spent in *all* NMIs
that occur on the given CPU during the (active portion of the)
sampling window. However, the code seems to be overwriting this
variable for each NMI, thereby only recording the time spent in the
most recent NMI. Fix it by accumulating the duration instead.

Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu

Fixes: 7b2c862501 ("tracing: Add NMI tracing in hwlat detector")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:49:33 -04:00
Steven Rostedt (VMware)
17911ff38a tracing: Add locked_down checks to the open calls of files created for tracefs
Added various checks on open tracefs calls to see if tracefs is in lockdown
mode, and if so, to return -EPERM.

Note, the event format files (which are basically standard on all machines)
as well as the enabled_functions file (which shows what is currently being
traced) are not lockde down. Perhaps they should be, but it seems counter
intuitive to lockdown information to help you know if the system has been
modified.

Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:48:06 -04:00
Steven Rostedt (VMware)
8530dec63e tracing: Add tracing_check_open_get_tr()
Currently, most files in the tracefs directory test if tracing_disabled is
set. If so, it should return -ENODEV. The tracing_disabled is called when
tracing is found to be broken. Originally it was done in case the ring
buffer was found to be corrupted, and we wanted to prevent reading it from
crashing the kernel. But it's also called if a tracing selftest fails on
boot. It's a one way switch. That is, once it is triggered, tracing is
disabled until reboot.

As most tracefs files can also be used by instances in the tracefs
directory, they need to be carefully done. Each instance has a trace_array
associated to it, and when the instance is removed, the trace_array is
freed. But if an instance is opened with a reference to the trace_array,
then it requires looking up the trace_array to get its ref counter (as there
could be a race with it being deleted and the open itself). Once it is
found, a reference is added to prevent the instance from being removed (and
the trace_array associated with it freed).

Combine the two checks (tracing_disabled and trace_array_get()) into a
single helper function. This will also make it easier to add lockdown to
tracefs later.

Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:44:07 -04:00
Steven Rostedt (VMware)
aa07d71f1b tracing: Have trace events system open call tracing_open_generic_tr()
Instead of having the trace events system open call open code the taking of
the trace_array descriptor (with trace_array_get()) and then calling
trace_open_generic(), have it use the tracing_open_generic_tr() that does
the combination of the two. This requires making tracing_open_generic_tr()
global.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:43:00 -04:00
Steven Rostedt (VMware)
194c2c74f5 tracing: Get trace_array reference for available_tracers files
As instances may have different tracers available, we need to look at the
trace_array descriptor that shows the list of the available tracers for the
instance. But there's a race between opening the file and an admin
deleting the instance. The trace_array_get() needs to be called before
accessing the trace_array.

Cc: stable@vger.kernel.org
Fixes: 607e2ea167 ("tracing: Set up infrastructure to allow tracers for instances")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:40:50 -04:00
Steven Rostedt (VMware)
9ef16693af ftrace: Get a reference counter for the trace_array on filter files
The ftrace set_ftrace_filter and set_ftrace_notrace files are specific for
an instance now. They need to take a reference to the instance otherwise
there could be a race between accessing the files and deleting the instance.

It wasn't until the :mod: caching where these file operations started
referencing the trace_array directly.

Cc: stable@vger.kernel.org
Fixes: 673feb9d76 ("ftrace: Add :mod: caching infrastructure to trace_array")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12 20:40:21 -04:00
Linus Torvalds
cf4f493b10 A few more tracing fixes:
- Fixed a buffer overflow by checking nr_args correctly in probes
 
  - Fixed a warning that is reported by clang
 
  - Fixed a possible memory leak in error path of filter processing
 
  - Fixed the selftest that checks for failures, but wasn't failing
 
  - Minor clean up on call site output of a memory trace event
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Merge tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "A few more tracing fixes:

   - Fix a buffer overflow by checking nr_args correctly in probes

   - Fix a warning that is reported by clang

   - Fix a possible memory leak in error path of filter processing

   - Fix the selftest that checks for failures, but wasn't failing

   - Minor clean up on call site output of a memory trace event"

* tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests/ftrace: Fix same probe error test
  mm, tracing: Print symbol name for call_site in trace events
  tracing: Have error path in predicate_parse() free its allocated memory
  tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
  tracing/probe: Fix to check the difference of nr_args before adding probe
2019-09-30 09:29:53 -07:00
Linus Torvalds
02dc96ef6c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Sanity check URB networking device parameters to avoid divide by
    zero, from Oliver Neukum.

 2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
    don't work properly. Longer term this needs a better fix tho. From
    Vijay Khemka.

 3) Small fixes to selftests (use ping when ping6 is not present, etc.)
    from David Ahern.

 4) Bring back rt_uses_gateway member of struct rtable, it's semantics
    were not well understood and trying to remove it broke things. From
    David Ahern.

 5) Move usbnet snaity checking, ignore endpoints with invalid
    wMaxPacketSize. From Bjørn Mork.

 6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.

 7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
    Alex Vesker, and Yevgeny Kliteynik

 8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.

 9) Fix crash when removing sch_cbs entry while offloading is enabled,
    from Vinicius Costa Gomes.

10) Signedness bug fixes, generally in looking at the result given by
    of_get_phy_mode() and friends. From Dan Crapenter.

11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.

12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.

13) Fix quantization code in tcp_bbr, from Kevin Yang.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
  net: tap: clean up an indentation issue
  nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
  tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
  sk_buff: drop all skb extensions on free and skb scrubbing
  tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
  mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
  Documentation: Clarify trap's description
  mlxsw: spectrum: Clear VLAN filters during port initialization
  net: ena: clean up indentation issue
  NFC: st95hf: clean up indentation issue
  net: phy: micrel: add Asym Pause workaround for KSZ9021
  net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
  ptp: correctly disable flags on old ioctls
  lib: dimlib: fix help text typos
  net: dsa: microchip: Always set regmap stride to 1
  nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
  nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
  net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
  vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
  net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
  ...
2019-09-28 17:47:33 -07:00
Navid Emamdoost
96c5c6e6a5 tracing: Have error path in predicate_parse() free its allocated memory
In predicate_parse, there is an error path that is not going to
out_free instead it returns directly which leads to a memory leak.

Link: http://lkml.kernel.org/r/20190920225800.3870-1-navid.emamdoost@gmail.com

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-28 17:13:39 -04:00
Nathan Chancellor
968e517093 tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
After r372664 in clang, the IF_ASSIGN macro causes a couple hundred
warnings along the lines of:

kernel/trace/trace_output.c:1331:2: warning: converting the enum
constant to a boolean [-Wint-in-bool-context]
kernel/trace/trace.h:409:3: note: expanded from macro
'trace_assign_type'
                IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,
                ^
kernel/trace/trace.h:371:14: note: expanded from macro 'IF_ASSIGN'
                WARN_ON(id && (entry)->type != id);     \
                           ^
264 warnings generated.

This warning can catch issues with constructs like:

    if (state == A || B)

where the developer really meant:

    if (state == A || state == B)

This is currently the only occurrence of the warning in the kernel
tree across defconfig, allyesconfig, allmodconfig for arm32, arm64,
and x86_64. Add the implicit '!= 0' to the WARN_ON statement to fix
the warnings and find potential issues in the future.

Link: 28b38c277a
Link: https://github.com/ClangBuiltLinux/linux/issues/686
Link: http://lkml.kernel.org/r/20190926162258.466321-1-natechancellor@gmail.com

Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-28 17:13:39 -04:00
Masami Hiramatsu
d2aea95a1a tracing/probe: Fix to check the difference of nr_args before adding probe
Steven reported that a test triggered:

==================================================================
 BUG: KASAN: slab-out-of-bounds in trace_kprobe_create+0xa9e/0xe40
 Read of size 8 at addr ffff8880c4f25a48 by task ftracetest/4798

 CPU: 2 PID: 4798 Comm: ftracetest Not tainted 5.3.0-rc6-test+ #30
 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
 Call Trace:
  dump_stack+0x7c/0xc0
  ? trace_kprobe_create+0xa9e/0xe40
  print_address_description+0x6c/0x332
  ? trace_kprobe_create+0xa9e/0xe40
  ? trace_kprobe_create+0xa9e/0xe40
  __kasan_report.cold.6+0x1a/0x3b
  ? trace_kprobe_create+0xa9e/0xe40
  kasan_report+0xe/0x12
  trace_kprobe_create+0xa9e/0xe40
  ? print_kprobe_event+0x280/0x280
  ? match_held_lock+0x1b/0x240
  ? find_held_lock+0xac/0xd0
  ? fs_reclaim_release.part.112+0x5/0x20
  ? lock_downgrade+0x350/0x350
  ? kasan_unpoison_shadow+0x30/0x40
  ? __kasan_kmalloc.constprop.6+0xc1/0xd0
  ? trace_kprobe_create+0xe40/0xe40
  ? trace_kprobe_create+0xe40/0xe40
  create_or_delete_trace_kprobe+0x2e/0x60
  trace_run_command+0xc3/0xe0
  ? trace_panic_handler+0x20/0x20
  ? kasan_unpoison_shadow+0x30/0x40
  trace_parse_run_command+0xdc/0x163
  vfs_write+0xe1/0x240
  ksys_write+0xba/0x150
  ? __ia32_sys_read+0x50/0x50
  ? tracer_hardirqs_on+0x61/0x180
  ? trace_hardirqs_off_caller+0x43/0x110
  ? mark_held_locks+0x29/0xa0
  ? do_syscall_64+0x14/0x260
  do_syscall_64+0x68/0x260

Fix to check the difference of nr_args before adding probe
on existing probes. This also may set the error log index
bigger than the number of command parameters. In that case
it sets the error position is next to the last parameter.

Link: http://lkml.kernel.org/r/156966474783.3478.13217501608215769150.stgit@devnote2

Fixes: ca89bc071d ("tracing/kprobe: Add multi-probe per event support")
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-28 17:07:53 -04:00
Linus Torvalds
aefcf2f4b5 Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
 "This is the latest iteration of the kernel lockdown patchset, from
  Matthew Garrett, David Howells and others.

  From the original description:

    This patchset introduces an optional kernel lockdown feature,
    intended to strengthen the boundary between UID 0 and the kernel.
    When enabled, various pieces of kernel functionality are restricted.
    Applications that rely on low-level access to either hardware or the
    kernel may cease working as a result - therefore this should not be
    enabled without appropriate evaluation beforehand.

    The majority of mainstream distributions have been carrying variants
    of this patchset for many years now, so there's value in providing a
    doesn't meet every distribution requirement, but gets us much closer
    to not requiring external patches.

  There are two major changes since this was last proposed for mainline:

   - Separating lockdown from EFI secure boot. Background discussion is
     covered here: https://lwn.net/Articles/751061/

   -  Implementation as an LSM, with a default stackable lockdown LSM
      module. This allows the lockdown feature to be policy-driven,
      rather than encoding an implicit policy within the mechanism.

  The new locked_down LSM hook is provided to allow LSMs to make a
  policy decision around whether kernel functionality that would allow
  tampering with or examining the runtime state of the kernel should be
  permitted.

  The included lockdown LSM provides an implementation with a simple
  policy intended for general purpose use. This policy provides a coarse
  level of granularity, controllable via the kernel command line:

    lockdown={integrity|confidentiality}

  Enable the kernel lockdown feature. If set to integrity, kernel features
  that allow userland to modify the running kernel are disabled. If set to
  confidentiality, kernel features that allow userland to extract
  confidential information from the kernel are also disabled.

  This may also be controlled via /sys/kernel/security/lockdown and
  overriden by kernel configuration.

  New or existing LSMs may implement finer-grained controls of the
  lockdown features. Refer to the lockdown_reason documentation in
  include/linux/security.h for details.

  The lockdown feature has had signficant design feedback and review
  across many subsystems. This code has been in linux-next for some
  weeks, with a few fixes applied along the way.

  Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
  when kernel lockdown is in confidentiality mode") is missing a
  Signed-off-by from its author. Matthew responded that he is providing
  this under category (c) of the DCO"

* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
  kexec: Fix file verification on S390
  security: constify some arrays in lockdown LSM
  lockdown: Print current->comm in restriction messages
  efi: Restrict efivar_ssdt_load when the kernel is locked down
  tracefs: Restrict tracefs when the kernel is locked down
  debugfs: Restrict debugfs when the kernel is locked down
  kexec: Allow kexec_file() with appropriate IMA policy when locked down
  lockdown: Lock down perf when in confidentiality mode
  bpf: Restrict bpf when kernel lockdown is in confidentiality mode
  lockdown: Lock down tracing and perf kprobes when in confidentiality mode
  lockdown: Lock down /proc/kcore
  x86/mmiotrace: Lock down the testmmiotrace module
  lockdown: Lock down module params that specify hardware parameters (eg. ioport)
  lockdown: Lock down TIOCSSERIAL
  lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
  acpi: Disable ACPI table override if the kernel is locked down
  acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
  ACPI: Limit access to custom_method when the kernel is locked down
  x86/msr: Restrict MSR access when the kernel is locked down
  x86: Lock down IO port access when the kernel is locked down
  ...
2019-09-28 08:14:15 -07:00
Allan Zhang
768fb61fcc bpf: Fix bpf_event_output re-entry issue
BPF_PROG_TYPE_SOCK_OPS program can reenter bpf_event_output because it
can be called from atomic and non-atomic contexts since we don't have
bpf_prog_active to prevent it happen.

This patch enables 3 levels of nesting to support normal, irq and nmi
context.

We can easily reproduce the issue by running netperf crr mode with 100
flows and 10 threads from netperf client side.

Here is the whole stack dump:

[  515.228898] WARNING: CPU: 20 PID: 14686 at kernel/trace/bpf_trace.c:549 bpf_event_output+0x1f9/0x220
[  515.228903] CPU: 20 PID: 14686 Comm: tcp_crr Tainted: G        W        4.15.0-smp-fixpanic #44
[  515.228904] Hardware name: Intel TBG,ICH10/Ikaria_QC_1b, BIOS 1.22.0 06/04/2018
[  515.228905] RIP: 0010:bpf_event_output+0x1f9/0x220
[  515.228906] RSP: 0018:ffff9a57ffc03938 EFLAGS: 00010246
[  515.228907] RAX: 0000000000000012 RBX: 0000000000000001 RCX: 0000000000000000
[  515.228907] RDX: 0000000000000000 RSI: 0000000000000096 RDI: ffffffff836b0f80
[  515.228908] RBP: ffff9a57ffc039c8 R08: 0000000000000004 R09: 0000000000000012
[  515.228908] R10: ffff9a57ffc1de40 R11: 0000000000000000 R12: 0000000000000002
[  515.228909] R13: ffff9a57e13bae00 R14: 00000000ffffffff R15: ffff9a57ffc1e2c0
[  515.228910] FS:  00007f5a3e6ec700(0000) GS:ffff9a57ffc00000(0000) knlGS:0000000000000000
[  515.228910] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  515.228911] CR2: 0000537082664fff CR3: 000000061fed6002 CR4: 00000000000226f0
[  515.228911] Call Trace:
[  515.228913]  <IRQ>
[  515.228919]  [<ffffffff82c6c6cb>] bpf_sockopt_event_output+0x3b/0x50
[  515.228923]  [<ffffffff8265daee>] ? bpf_ktime_get_ns+0xe/0x10
[  515.228927]  [<ffffffff8266fda5>] ? __cgroup_bpf_run_filter_sock_ops+0x85/0x100
[  515.228930]  [<ffffffff82cf90a5>] ? tcp_init_transfer+0x125/0x150
[  515.228933]  [<ffffffff82cf9159>] ? tcp_finish_connect+0x89/0x110
[  515.228936]  [<ffffffff82cf98e4>] ? tcp_rcv_state_process+0x704/0x1010
[  515.228939]  [<ffffffff82c6e263>] ? sk_filter_trim_cap+0x53/0x2a0
[  515.228942]  [<ffffffff82d90d1f>] ? tcp_v6_inbound_md5_hash+0x6f/0x1d0
[  515.228945]  [<ffffffff82d92160>] ? tcp_v6_do_rcv+0x1c0/0x460
[  515.228947]  [<ffffffff82d93558>] ? tcp_v6_rcv+0x9f8/0xb30
[  515.228951]  [<ffffffff82d737c0>] ? ip6_route_input+0x190/0x220
[  515.228955]  [<ffffffff82d5f7ad>] ? ip6_protocol_deliver_rcu+0x6d/0x450
[  515.228958]  [<ffffffff82d60246>] ? ip6_rcv_finish+0xb6/0x170
[  515.228961]  [<ffffffff82d5fb90>] ? ip6_protocol_deliver_rcu+0x450/0x450
[  515.228963]  [<ffffffff82d60361>] ? ipv6_rcv+0x61/0xe0
[  515.228966]  [<ffffffff82d60190>] ? ipv6_list_rcv+0x330/0x330
[  515.228969]  [<ffffffff82c4976b>] ? __netif_receive_skb_one_core+0x5b/0xa0
[  515.228972]  [<ffffffff82c497d1>] ? __netif_receive_skb+0x21/0x70
[  515.228975]  [<ffffffff82c4a8d2>] ? process_backlog+0xb2/0x150
[  515.228978]  [<ffffffff82c4aadf>] ? net_rx_action+0x16f/0x410
[  515.228982]  [<ffffffff830000dd>] ? __do_softirq+0xdd/0x305
[  515.228986]  [<ffffffff8252cfdc>] ? irq_exit+0x9c/0xb0
[  515.228989]  [<ffffffff82e02de5>] ? smp_call_function_single_interrupt+0x65/0x120
[  515.228991]  [<ffffffff82e020e1>] ? call_function_single_interrupt+0x81/0x90
[  515.228992]  </IRQ>
[  515.228996]  [<ffffffff82a11ff0>] ? io_serial_in+0x20/0x20
[  515.229000]  [<ffffffff8259c040>] ? console_unlock+0x230/0x490
[  515.229003]  [<ffffffff8259cbaa>] ? vprintk_emit+0x26a/0x2a0
[  515.229006]  [<ffffffff8259cbff>] ? vprintk_default+0x1f/0x30
[  515.229008]  [<ffffffff8259d9f5>] ? vprintk_func+0x35/0x70
[  515.229011]  [<ffffffff8259d4bb>] ? printk+0x50/0x66
[  515.229013]  [<ffffffff82637637>] ? bpf_event_output+0xb7/0x220
[  515.229016]  [<ffffffff82c6c6cb>] ? bpf_sockopt_event_output+0x3b/0x50
[  515.229019]  [<ffffffff8265daee>] ? bpf_ktime_get_ns+0xe/0x10
[  515.229023]  [<ffffffff82c29e87>] ? release_sock+0x97/0xb0
[  515.229026]  [<ffffffff82ce9d6a>] ? tcp_recvmsg+0x31a/0xda0
[  515.229029]  [<ffffffff8266fda5>] ? __cgroup_bpf_run_filter_sock_ops+0x85/0x100
[  515.229032]  [<ffffffff82ce77c1>] ? tcp_set_state+0x191/0x1b0
[  515.229035]  [<ffffffff82ced10e>] ? tcp_disconnect+0x2e/0x600
[  515.229038]  [<ffffffff82cecbbb>] ? tcp_close+0x3eb/0x460
[  515.229040]  [<ffffffff82d21082>] ? inet_release+0x42/0x70
[  515.229043]  [<ffffffff82d58809>] ? inet6_release+0x39/0x50
[  515.229046]  [<ffffffff82c1f32d>] ? __sock_release+0x4d/0xd0
[  515.229049]  [<ffffffff82c1f3e5>] ? sock_close+0x15/0x20
[  515.229052]  [<ffffffff8273b517>] ? __fput+0xe7/0x1f0
[  515.229055]  [<ffffffff8273b66e>] ? ____fput+0xe/0x10
[  515.229058]  [<ffffffff82547bf2>] ? task_work_run+0x82/0xb0
[  515.229061]  [<ffffffff824086df>] ? exit_to_usermode_loop+0x7e/0x11f
[  515.229064]  [<ffffffff82408171>] ? do_syscall_64+0x111/0x130
[  515.229067]  [<ffffffff82e0007c>] ? entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: a5a3a828cd ("bpf: add perf event notificaton support for sock_ops")
Signed-off-by: Allan Zhang <allanzhang@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20190925234312.94063-2-allanzhang@google.com
2019-09-27 11:24:29 +02:00
Linus Torvalds
7897c04ad0 Srikar Dronamraju fixed a bug in the newmulti probe code.
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Merge tag 'trace-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Srikar Dronamraju fixed a bug in the newmulti probe code"

* tag 'trace-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/probe: Fix same probe event argument matching
2019-09-26 13:07:38 -07:00
Srikar Dronamraju
f8d7ab2bde tracing/probe: Fix same probe event argument matching
Commit fe60b0ce8e ("tracing/probe: Reject exactly same probe event")
tries to reject a event which matches an already existing probe.

However it currently continues to match arguments and rejects adding a
probe even when the arguments don't match. Fix this by only rejecting a
probe if and only if all the arguments match.

Link: http://lkml.kernel.org/r/20190924114906.14038-1-srikar@linux.vnet.ibm.com

Fixes: fe60b0ce8e ("tracing/probe: Reject exactly same probe event")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-25 06:34:06 -04:00
Linus Torvalds
45824fc0da powerpc updates for 5.4
- Initial support for running on a system with an Ultravisor, which is software
    that runs below the hypervisor and protects guests against some attacks by
    the hypervisor.
 
  - Support for building the kernel to run as a "Secure Virtual Machine", ie. as
    a guest capable of running on a system with an Ultravisor.
 
  - Some changes to our DMA code on bare metal, to allow devices with medium
    sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space.
 
  - Support for firmware assisted crash dumps on bare metal (powernv).
 
  - Two series fixing bugs in and refactoring our PCI EEH code.
 
  - A large series refactoring our exception entry code to use gas macros, both
    to make it more readable and also enable some future optimisations.
 
 As well as many cleanups and other minor features & fixups.
 
 Thanks to:
   Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh
   Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin
   Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy,
   Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens,
   David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar,
   Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari
   Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras,
   Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
   Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor,
   Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram
   Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj,
   Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung
   Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde.
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Merge tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "This is a bit late, partly due to me travelling, and partly due to a
  power outage knocking out some of my test systems *while* I was
  travelling.

   - Initial support for running on a system with an Ultravisor, which
     is software that runs below the hypervisor and protects guests
     against some attacks by the hypervisor.

   - Support for building the kernel to run as a "Secure Virtual
     Machine", ie. as a guest capable of running on a system with an
     Ultravisor.

   - Some changes to our DMA code on bare metal, to allow devices with
     medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of
     DMA space.

   - Support for firmware assisted crash dumps on bare metal (powernv).

   - Two series fixing bugs in and refactoring our PCI EEH code.

   - A large series refactoring our exception entry code to use gas
     macros, both to make it more readable and also enable some future
     optimisations.

  As well as many cleanups and other minor features & fixups.

  Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew
  Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual,
  Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe
  JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig,
  Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand,
  Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg
  Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim
  Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo
  Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
  Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver
  O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm,
  Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu,
  Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom
  Lendacky, Vasant Hegde"

* tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits)
  powerpc/mm/mce: Keep irqs disabled during lockless page table walk
  powerpc: Use ftrace_graph_ret_addr() when unwinding
  powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
  ftrace: Look up the address of return_to_handler() using helpers
  powerpc: dump kernel log before carrying out fadump or kdump
  docs: powerpc: Add missing documentation reference
  powerpc/xmon: Fix output of XIVE IPI
  powerpc/xmon: Improve output of XIVE interrupts
  powerpc/mm/radix: remove useless kernel messages
  powerpc/fadump: support holes in kernel boot memory area
  powerpc/fadump: remove RMA_START and RMA_END macros
  powerpc/fadump: update documentation about option to release opalcore
  powerpc/fadump: consider f/w load area
  powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file
  powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes
  powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP
  powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
  powerpc/fadump: improve how crashed kernel's memory is reserved
  powerpc/fadump: consider reserved ranges while releasing memory
  powerpc/fadump: make crash memory ranges array allocation generic
  ...
2019-09-20 11:48:06 -07:00
Linus Torvalds
45979a956b Tracing updates:
- Addition of multiprobes to kprobe and uprobe events
    Allows for more than one probe attached to the same location
 
  - Addition of adding immediates to probe parameters
 
  - Clean up of the recordmcount.c code. This brings us closer
    to merging recordmcount into objtool, and reuse code.
 
  - Other small clean ups
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Merge tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Addition of multiprobes to kprobe and uprobe events (allows for more
   than one probe attached to the same location)

 - Addition of adding immediates to probe parameters

 - Clean up of the recordmcount.c code. This brings us closer to merging
   recordmcount into objtool, and reuse code.

 - Other small clean ups

* tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
  selftests/ftrace: Update kprobe event error testcase
  tracing/probe: Reject exactly same probe event
  tracing/probe: Fix to allow user to enable events on unloaded modules
  selftests/ftrace: Select an existing function in kprobe_eventname test
  tracing/kprobe: Fix NULL pointer access in trace_porbe_unlink()
  tracing: Make sure variable reference alias has correct var_ref_idx
  tracing: Be more clever when dumping hex in __print_hex()
  ftrace: Simplify ftrace hash lookup code in clear_func_from_hash()
  tracing: Add "gfp_t" support in synthetic_events
  tracing: Rename tracing_reset() to tracing_reset_cpu()
  tracing: Document the stack trace algorithm in the comments
  tracing/arm64: Have max stack tracer handle the case of return address after data
  recordmcount: Clarify what cleanup() does
  recordmcount: Remove redundant cleanup() calls
  recordmcount: Kernel style formatting
  recordmcount: Kernel style function signature formatting
  recordmcount: Rewrite error/success handling
  selftests/ftrace: Add syntax error test for multiprobe
  selftests/ftrace: Add syntax error test for immediates
  selftests/ftrace: Add a testcase for kprobe multiprobe event
  ...
2019-09-20 11:19:48 -07:00
Masami Hiramatsu
fe60b0ce8e tracing/probe: Reject exactly same probe event
Reject exactly same probe events as existing probes.

Multiprobe allows user to define multiple probes on same
event. If user appends a probe which exactly same definition
(same probe address and same arguments) on existing event,
the event will record same probe information twice.
That can be confusing users, so reject it.

Link: http://lkml.kernel.org/r/156879694602.31056.5533024778165036763.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-19 11:09:16 -04:00
Masami Hiramatsu
44d00dc7ce tracing/probe: Fix to allow user to enable events on unloaded modules
Fix to allow user to enable probe events on unloaded modules.

This operations was allowed before commit 60d53e2c3b ("tracing/probe:
Split trace_event related data from trace_probe"), because if users
need to probe module init functions, they have to enable those probe
events before loading module.

Link: http://lkml.kernel.org/r/156879693733.31056.9331322616994665167.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 60d53e2c3b ("tracing/probe: Split trace_event related data from trace_probe")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-19 09:55:42 -04:00
Linus Torvalds
81160dda9a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski.

 2) Use bio_vec in the networking instead of custom skb_frag_t, from
    Matthew Wilcox.

 3) Make use of xmit_more in r8169 driver, from Heiner Kallweit.

 4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen.

 5) Support all variants of 5750X bnxt_en chips, from Michael Chan.

 6) More RTNL avoidance work in the core and mlx5 driver, from Vlad
    Buslov.

 7) Add TCP syn cookies bpf helper, from Petar Penkov.

 8) Add 'nettest' to selftests and use it, from David Ahern.

 9) Add extack support to drop_monitor, add packet alert mode and
    support for HW drops, from Ido Schimmel.

10) Add VLAN offload to stmmac, from Jose Abreu.

11) Lots of devm_platform_ioremap_resource() conversions, from
    YueHaibing.

12) Add IONIC driver, from Shannon Nelson.

13) Several kTLS cleanups, from Jakub Kicinski.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits)
  mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer
  mlxsw: spectrum: Register CPU port with devlink
  mlxsw: spectrum_buffers: Prevent changing CPU port's configuration
  net: ena: fix incorrect update of intr_delay_resolution
  net: ena: fix retrieval of nonadaptive interrupt moderation intervals
  net: ena: fix update of interrupt moderation register
  net: ena: remove all old adaptive rx interrupt moderation code from ena_com
  net: ena: remove ena_restore_ethtool_params() and relevant fields
  net: ena: remove old adaptive interrupt moderation code from ena_netdev
  net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*()
  net: ena: enable the interrupt_moderation in driver_supported_features
  net: ena: reimplement set/get_coalesce()
  net: ena: switch to dim algorithm for rx adaptive interrupt moderation
  net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it
  net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable
  ethtool: implement Energy Detect Powerdown support via phy-tunable
  xen-netfront: do not assume sk_buff_head list is empty in error handling
  s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb”
  net: ena: don't wake up tx queue when down
  drop_monitor: Better sanitize notified packets
  ...
2019-09-18 12:34:53 -07:00
Naveen N. Rao
a3db31ff6c ftrace: Look up the address of return_to_handler() using helpers
This ensures that we use the right address on architectures that use
function descriptors.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8f6f14d192a994008ac370ce14036bbe67224c7d.1567707399.git.naveen.n.rao@linux.vnet.ibm.com
2019-09-18 12:24:47 +10:00
Masami Hiramatsu
d59fae6fea tracing/kprobe: Fix NULL pointer access in trace_porbe_unlink()
Fix NULL pointer access in trace_probe_unlink() by initializing
trace_probe.list correctly in trace_probe_init().

In the error case of trace_probe_init(), it can call trace_probe_unlink()
before initializing trace_probe.list member. This causes NULL pointer
dereference at list_del_init() in trace_probe_unlink().

Syzbot reported :

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 8633 Comm: syz-executor797 Not tainted 5.3.0-rc8-next-20190915
#0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__list_del_entry_valid+0x85/0xf5 lib/list_debug.c:51
Code: 0f 84 e1 00 00 00 48 b8 22 01 00 00 00 00 ad de 49 39 c4 0f 84 e2 00
00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 75
53 49 8b 14 24 4c 39 f2 0f 85 99 00 00 00 49 8d 7d
RSP: 0018:ffff888090a7f9d8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff88809b6f90c0 RCX: ffffffff817c0ca9
RDX: 0000000000000000 RSI: ffffffff817c0a73 RDI: ffff88809b6f90c8
RBP: ffff888090a7f9f0 R08: ffff88809a04e600 R09: ffffed1015d26aed
R10: ffffed1015d26aec R11: ffff8880ae935763 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88809b6f90c0 R15: ffff88809b6f90d0
FS:  0000555556f99880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000006cc090 CR3: 00000000962b2000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  __list_del_entry include/linux/list.h:131 [inline]
  list_del_init include/linux/list.h:190 [inline]
  trace_probe_unlink+0x1f/0x200 kernel/trace/trace_probe.c:959
  trace_probe_cleanup+0xd3/0x110 kernel/trace/trace_probe.c:973
  trace_probe_init+0x3f2/0x510 kernel/trace/trace_probe.c:1011
  alloc_trace_uprobe+0x5e/0x250 kernel/trace/trace_uprobe.c:353
  create_local_trace_uprobe+0x109/0x4a0 kernel/trace/trace_uprobe.c:1508
  perf_uprobe_init+0x131/0x210 kernel/trace/trace_event_perf.c:314
  perf_uprobe_event_init+0x106/0x1a0 kernel/events/core.c:8898
  perf_try_init_event+0x135/0x590 kernel/events/core.c:10184
  perf_init_event kernel/events/core.c:10228 [inline]
  perf_event_alloc.part.0+0x1b89/0x33d0 kernel/events/core.c:10505
  perf_event_alloc kernel/events/core.c:10887 [inline]
  __do_sys_perf_event_open+0xa2d/0x2d00 kernel/events/core.c:10989
  __se_sys_perf_event_open kernel/events/core.c:10871 [inline]
  __x64_sys_perf_event_open+0xbe/0x150 kernel/events/core.c:10871
  do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Link: http://lkml.kernel.org/r/156869709721.22406.5153754822203046939.stgit@devnote2

Reported-by: syzbot+2f807f4d3a2a4e87f18f@syzkaller.appspotmail.com
Fixes: ca89bc071d ("tracing/kprobe: Add multi-probe per event support")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-17 11:21:29 -04:00
Tom Zanussi
17f8607a16 tracing: Make sure variable reference alias has correct var_ref_idx
Original changelog from Steve Rostedt (except last sentence which
explains the problem, and the Fixes: tag):

I performed a three way histogram with the following commands:

echo 'irq_lat u64 lat pid_t pid' > synthetic_events
echo 'wake_lat u64 lat u64 irqlat pid_t pid' >> synthetic_events
echo 'hist:keys=common_pid:irqts=common_timestamp.usecs if function == 0xffffffff81200580' > events/timer/hrtimer_start/trigger
echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$irqts:onmatch(timer.hrtimer_start).irq_lat($lat,pid) if common_flags & 1' > events/sched/sched_waking/trigger
echo 'hist:keys=pid:wakets=common_timestamp.usecs,irqlat=lat' > events/synthetic/irq_lat/trigger
echo 'hist:keys=next_pid:lat=common_timestamp.usecs-$wakets,irqlat=$irqlat:onmatch(synthetic.irq_lat).wake_lat($lat,$irqlat,next_pid)' > events/sched/sched_switch/trigger
echo 1 > events/synthetic/wake_lat/enable

Basically I wanted to see:

 hrtimer_start (calling function tick_sched_timer)

Note:

  # grep tick_sched_timer /proc/kallsyms
ffffffff81200580 t tick_sched_timer

And save the time of that, and then record sched_waking if it is called
in interrupt context and with the same pid as the hrtimer_start, it
will record the latency between that and the waking event.

I then look at when the task that is woken is scheduled in, and record
the latency between the wakeup and the task running.

At the end, the wake_lat synthetic event will show the wakeup to
scheduled latency, as well as the irq latency in from hritmer_start to
the wakeup. The problem is that I found this:

          <idle>-0     [007] d...   190.485261: wake_lat: lat=27 irqlat=190485230 pid=698
          <idle>-0     [005] d...   190.485283: wake_lat: lat=40 irqlat=190485239 pid=10
          <idle>-0     [002] d...   190.488327: wake_lat: lat=56 irqlat=190488266 pid=335
          <idle>-0     [005] d...   190.489330: wake_lat: lat=64 irqlat=190489262 pid=10
          <idle>-0     [003] d...   190.490312: wake_lat: lat=43 irqlat=190490265 pid=77
          <idle>-0     [005] d...   190.493322: wake_lat: lat=54 irqlat=190493262 pid=10
          <idle>-0     [005] d...   190.497305: wake_lat: lat=35 irqlat=190497267 pid=10
          <idle>-0     [005] d...   190.501319: wake_lat: lat=50 irqlat=190501264 pid=10

The irqlat seemed quite large! Investigating this further, if I had
enabled the irq_lat synthetic event, I noticed this:

          <idle>-0     [002] d.s.   249.429308: irq_lat: lat=164968 pid=335
          <idle>-0     [002] d...   249.429369: wake_lat: lat=55 irqlat=249429308 pid=335

Notice that the timestamp of the irq_lat "249.429308" is awfully
similar to the reported irqlat variable. In fact, all instances were
like this. It appeared that:

  irqlat=$irqlat

Wasn't assigning the old $irqlat to the new irqlat variable, but
instead was assigning the $irqts to it.

The issue is that assigning the old $irqlat to the new irqlat variable
creates a variable reference alias, but the alias creation code
forgets to make sure the alias uses the same var_ref_idx to access the
reference.

Link: http://lkml.kernel.org/r/1567375321.5282.12.camel@kernel.org

Cc: Linux Trace Devel <linux-trace-devel@vger.kernel.org>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 7e8b88a30b ("tracing: Add hist trigger support for variable reference aliases")
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-17 11:21:29 -04:00
Andy Shevchenko
119cdbdb95 tracing: Be more clever when dumping hex in __print_hex()
Hex dump as many as 16 bytes at once in trace_print_hex_seq()
instead of byte-by-byte approach.

Link: http://lkml.kernel.org/r/20190806151543.86061-1-andriy.shevchenko@linux.intel.com

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-17 11:21:28 -04:00
Changbin Du
08468754c1 ftrace: Simplify ftrace hash lookup code in clear_func_from_hash()
Function ftrace_lookup_ip() will check empty hash table. So we don't
need extra check outside.

Link: http://lkml.kernel.org/r/20190910143336.13472-1-changbin.du@gmail.com

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-17 11:21:20 -04:00
Linus Torvalds
7e67a85999 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
   Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
   Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.

   As perf and the scheduler is getting bigger and more complex,
   document the status quo of current responsibilities and interests,
   and spread the review pain^H^H^H^H fun via an increase in the Cc:
   linecount generated by scripts/get_maintainer.pl. :-)

 - Add another series of patches that brings the -rt (PREEMPT_RT) tree
   closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
   into a new CONFIG_PREEMPTION category that will allow the eventual
   introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
   to go though.

 - Extend the CPU cgroup controller with uclamp.min and uclamp.max to
   allow the finer shaping of CPU bandwidth usage.

 - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).

 - Improve the behavior of high CPU count, high thread count
   applications running under cpu.cfs_quota_us constraints.

 - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.

 - Improve CPU isolation housekeeping CPU allocation NUMA locality.

 - Fix deadline scheduler bandwidth calculations and logic when cpusets
   rebuilds the topology, or when it gets deadline-throttled while it's
   being offlined.

 - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
   setscheduler() system calls without creating global serialization.
   Add new synchronization between cpuset topology-changing events and
   the deadline acceptance tests in setscheduler(), which were broken
   before.

 - Rework the active_mm state machine to be less confusing and more
   optimal.

 - Rework (simplify) the pick_next_task() slowpath.

 - Improve load-balancing on AMD EPYC systems.

 - ... and misc cleanups, smaller fixes and improvements - please see
   the Git log for more details.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
  sched/psi: Correct overly pessimistic size calculation
  sched/fair: Speed-up energy-aware wake-ups
  sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
  sched/uclamp: Update CPU's refcount on TG's clamp changes
  sched/uclamp: Use TG's clamps to restrict TASK's clamps
  sched/uclamp: Propagate system defaults to the root group
  sched/uclamp: Propagate parent clamps
  sched/uclamp: Extend CPU's cgroup controller
  sched/topology: Improve load balancing on AMD EPYC systems
  arch, ia64: Make NUMA select SMP
  sched, perf: MAINTAINERS update, add submaintainers and reviewers
  sched/fair: Use rq_lock/unlock in online_fair_sched_group
  cpufreq: schedutil: fix equation in comment
  sched: Rework pick_next_task() slow-path
  sched: Allow put_prev_task() to drop rq->lock
  sched/fair: Expose newidle_balance()
  sched: Add task_struct pointer to sched_class::set_curr_task
  sched: Rework CPU hotplug task selection
  sched/{rt,deadline}: Fix set_next_task vs pick_next_task
  sched: Fix kerneldoc comment for ia64_set_curr_task
  ...
2019-09-16 17:25:49 -07:00
Linus Torvalds
94d18ee934 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "This cycle's RCU changes were:

   - A few more RCU flavor consolidation cleanups.

   - Updates to RCU's list-traversal macros improving lockdep usability.

   - Forward-progress improvements for no-CBs CPUs: Avoid ignoring
     incoming callbacks during grace-period waits.

   - Forward-progress improvements for no-CBs CPUs: Use ->cblist
     structure to take advantage of others' grace periods.

   - Also added a small commit that avoids needlessly inflicting
     scheduler-clock ticks on callback-offloaded CPUs.

   - Forward-progress improvements for no-CBs CPUs: Reduce contention on
     ->nocb_lock guarding ->cblist.

   - Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
     list to further reduce contention on ->nocb_lock guarding ->cblist.

   - Miscellaneous fixes.

   - Torture-test updates.

   - minor LKMM updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits)
  MAINTAINERS: Update from paulmck@linux.ibm.com to paulmck@kernel.org
  rcu: Don't include <linux/ktime.h> in rcutiny.h
  rcu: Allow rcu_do_batch() to dynamically adjust batch sizes
  rcu/nocb: Don't wake no-CBs GP kthread if timer posted under overload
  rcu/nocb: Reduce __call_rcu_nocb_wake() leaf rcu_node ->lock contention
  rcu/nocb: Reduce nocb_cb_wait() leaf rcu_node ->lock contention
  rcu/nocb: Advance CBs after merge in rcutree_migrate_callbacks()
  rcu/nocb: Avoid synchronous wakeup in __call_rcu_nocb_wake()
  rcu/nocb: Print no-CBs diagnostics when rcutorture writer unduly delayed
  rcu/nocb: EXP Check use and usefulness of ->nocb_lock_contended
  rcu/nocb: Add bypass callback queueing
  rcu/nocb: Atomic ->len field in rcu_segcblist structure
  rcu/nocb: Unconditionally advance and wake for excessive CBs
  rcu/nocb: Reduce ->nocb_lock contention with separate ->nocb_gp_lock
  rcu/nocb: Reduce contention at no-CBs invocation-done time
  rcu/nocb: Reduce contention at no-CBs registry-time CB advancement
  rcu/nocb: Round down for number of no-CBs grace-period kthreads
  rcu/nocb: Avoid ->nocb_lock capture by corresponding CPU
  rcu/nocb: Avoid needless wakeups of no-CBs grace-period kthread
  rcu/nocb: Make __call_rcu_nocb_wake() safe for many callbacks
  ...
2019-09-16 16:28:19 -07:00
Ingo Molnar
563c4f85f9 Merge branch 'sched/rt' into sched/core, to pick up -rt changes
Pick up the first couple of patches working towards PREEMPT_RT.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-09-16 14:05:04 +02:00
David S. Miller
1e46c09ec1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add the ability to use unaligned chunks in the AF_XDP umem. By
   relaxing where the chunks can be placed, it allows to use an
   arbitrary buffer size and place whenever there is a free
   address in the umem. Helps more seamless DPDK AF_XDP driver
   integration. Support for i40e, ixgbe and mlx5e, from Kevin and
   Maxim.

2) Addition of a wakeup flag for AF_XDP tx and fill rings so the
   application can wake up the kernel for rx/tx processing which
   avoids busy-spinning of the latter, useful when app and driver
   is located on the same core. Support for i40e, ixgbe and mlx5e,
   from Magnus and Maxim.

3) bpftool fixes for printf()-like functions so compiler can actually
   enforce checks, bpftool build system improvements for custom output
   directories, and addition of 'bpftool map freeze' command, from Quentin.

4) Support attaching/detaching XDP programs from 'bpftool net' command,
   from Daniel.

5) Automatic xskmap cleanup when AF_XDP socket is released, and several
   barrier/{read,write}_once fixes in AF_XDP code, from Björn.

6) Relicense of bpf_helpers.h/bpf_endian.h for future libbpf
   inclusion as well as libbpf versioning improvements, from Andrii.

7) Several new BPF kselftests for verifier precision tracking, from Alexei.

8) Several BPF kselftest fixes wrt endianess to run on s390x, from Ilya.

9) And more BPF kselftest improvements all over the place, from Stanislav.

10) Add simple BPF map op cache for nfp driver to batch dumps, from Jakub.

11) AF_XDP socket umem mapping improvements for 32bit archs, from Ivan.

12) Add BPF-to-BPF call and BTF line info support for s390x JIT, from Yauheni.

13) Small optimization in arm64 JIT to spare 1 insns for BPF_MOD, from Jerin.

14) Fix an error check in bpf_tcp_gen_syncookie() helper, from Petar.

15) Various minor fixes and cleanups, from Nathan, Masahiro, Masanari,
    Peter, Wei, Yue.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-06 16:49:17 +02:00
Zhengjun Xing
ac68154626 tracing: Add "gfp_t" support in synthetic_events
Add "gfp_t" support in synthetic_events, then the "gfp_t" type
parameter in some functions can be traced.

Prints the gfp flags as hex in addition to the human-readable flag
string.  Example output:

  whoopsie-630 [000] ...1 78.969452: testevent: bar=b20 (GFP_ATOMIC|__GFP_ZERO)
    rcuc/0-11  [000] ...1 81.097555: testevent: bar=a20 (GFP_ATOMIC)
    rcuc/0-11  [000] ...1 81.583123: testevent: bar=a20 (GFP_ATOMIC)

Link: http://lkml.kernel.org/r/20190712015308.9908-1-zhengjun.xing@linux.intel.com

Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
[ Added printing of flag names ]
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-05 11:35:14 -04:00
Steven Rostedt (VMware)
a47b53e95a tracing: Rename tracing_reset() to tracing_reset_cpu()
The name tracing_reset() was a misnomer, as it really only reset a single
CPU buffer. Rename it to tracing_reset_cpu() and also make it static and
remove the prototype from trace.h, as it is only used in a single function.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:40 -04:00
Steven Rostedt (VMware)
58fe7a87db tracing: Document the stack trace algorithm in the comments
As the max stack tracer algorithm is not that easy to understand from the
code, add comments that explain the algorithm and mentions how
ARCH_FTRACE_SHIFT_STACK_TRACER affects it.

Link: http://lkml.kernel.org/r/20190806123455.487ac02b@gandalf.local.home

Suggested-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:40 -04:00
Steven Rostedt (VMware)
f7edb451fa tracing/arm64: Have max stack tracer handle the case of return address after data
Most archs (well at least x86) store the function call return address on the
stack before storing the local variables for the function. The max stack
tracer depends on this in its algorithm to display the stack size of each
function it finds in the back trace.

Some archs (arm64), may store the return address (from its link register)
just before calling a nested function. There's no reason to save the link
register on leaf functions, as it wont be updated. This breaks the algorithm
of the max stack tracer.

Add a new define ARCH_FTRACE_SHIFT_STACK_TRACER that an architecture may set
if it stores the return address (link register) after it stores the
function's local variables, and have the stack trace shift the values of the
mapped stack size to the appropriate functions.

Link: 20190802094103.163576-1-jiping.ma2@windriver.com

Reported-by: Jiping Ma <jiping.ma2@windriver.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:40 -04:00
Masami Hiramatsu
a42e3c4de9 tracing/probe: Add immediate string parameter support
Add immediate string parameter (\"string") support to
probe events. This allows you to specify an immediate
(or dummy) parameter instead of fetching a string from
memory.

This feature looks odd, but imagine that you put a probe
on a code to trace some string data. If the code is
compiled into 2 instructions and 1 instruction has a
string on memory but other has no string since it is
optimized out. In that case, you can not fold those into
one event, even if ftrace supported multiple probes on
one event. With this feature, you can set a dummy string
like foo=\"(optimized)":string instead of something
like foo=+0(+0(%bp)):string.

Link: http://lkml.kernel.org/r/156095691687.28024.13372712423865047991.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:39 -04:00
Masami Hiramatsu
6218bf9f4d tracing/probe: Add immediate parameter support
Add immediate value parameter (\1234) support to
probe events. This allows you to specify an immediate
(or dummy) parameter instead of fetching from memory
or register.

This feature looks odd, but imagine when you put a probe
on a code to trace some data. If the code is compiled into
2 instructions and 1 instruction has a value but other has
nothing since it is optimized out.
In that case, you can not fold those into one event, even
if ftrace supported multiple probes on one event.
With this feature, you can set a dummy value like
foo=\deadbeef instead of something like foo=%di.

Link: http://lkml.kernel.org/r/156095690733.28024.13258186548822649469.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:39 -04:00
Masami Hiramatsu
ab10d69eb7 tracing/uprobe: Add per-probe delete from event
Add per-probe delete method from one event passing the head of
definition. In other words, the events which match the head
N parameters are deleted.

Link: http://lkml.kernel.org/r/156095689811.28024.221706761151739433.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:39 -04:00
Masami Hiramatsu
eb5bf81330 tracing/kprobe: Add per-probe delete from event
Allow user to delete a probe from event. This is done by head
match. For example, if we have 2 probes on an event

$ cat kprobe_events
p:kprobes/testprobe _do_fork r1=%ax r2=%dx
p:kprobes/testprobe idle_fork r1=%ax r2=%cx

Then you can remove one of them by passing the head of definition
which identify the probe.

$ echo "-:kprobes/testprobe idle_fork" >> kprobe_events

Link: http://lkml.kernel.org/r/156095688848.28024.15798690082378432435.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:38 -04:00
Masami Hiramatsu
41af3cf587 tracing/uprobe: Add multi-probe per uprobe event support
Allow user to define several probes on one uprobe event.
Note that this only support appending method. So deleting
event will delete all probes on the event.

Link: http://lkml.kernel.org/r/156095687876.28024.13840331032234992863.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:38 -04:00
Masami Hiramatsu
ca89bc071d tracing/kprobe: Add multi-probe per event support
Add multi-probe per one event support to kprobe events.
User can define several different probes on one trace event
if those events have same "event signature",
e.g.

  # echo p:testevent _do_fork > kprobe_events
  # echo p:testevent fork_idle >> kprobe_events
  # kprobe_events
  p:kprobes/testevent _do_fork
  p:kprobes/testevent fork_idle

The event signature is defined by kprobe type (retprobe or not),
the number of args, argument names, and argument types.

Note that this only support appending method. Delete event
operation will delete all probes on the event.

Link: http://lkml.kernel.org/r/156095686913.28024.9357292202316540742.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:38 -04:00
Masami Hiramatsu
30199137c8 tracing/dynevent: Pass extra arguments to match operation
Pass extra arguments to match operation for checking
exact match. If the event doesn't support exact match,
it will be ignored.

Link: http://lkml.kernel.org/r/156095685930.28024.10405547027475590975.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:38 -04:00
Masami Hiramatsu
cb8e7a8d55 tracing/dynevent: Delete all matched events
When user gives an event name to delete, delete all
matched events instead of the first one.

This means if there are several events which have same
name but different group (subsystem) name, those are
removed if user passed only the event name, e.g.

  # cat kprobe_events
  p:group1/testevent _do_fork
  p:group2/testevent fork_idle
  # echo -:testevent >> kprobe_events
  # cat kprobe_events
  #

Link: http://lkml.kernel.org/r/156095684958.28024.16597826267117453638.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:38 -04:00
Masami Hiramatsu
60d53e2c3b tracing/probe: Split trace_event related data from trace_probe
Split the trace_event related data from trace_probe data structure
and introduce trace_probe_event data structure for its folder.
This trace_probe_event data structure can have multiple trace_probe.

Link: http://lkml.kernel.org/r/156095683995.28024.7552150340561557873.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 12:19:38 -04:00
Jakub Kicinski
c68c9ec1c5 tracing: Correct kdoc formats
Fix the following kdoc warnings:

kernel/trace/trace.c:1579: warning: Function parameter or member 'tr' not described in 'update_max_tr_single'
kernel/trace/trace.c:1579: warning: Function parameter or member 'tsk' not described in 'update_max_tr_single'
kernel/trace/trace.c:1579: warning: Function parameter or member 'cpu' not described in 'update_max_tr_single'
kernel/trace/trace.c:1776: warning: Function parameter or member 'type' not described in 'register_tracer'
kernel/trace/trace.c:2239: warning: Function parameter or member 'task' not described in 'tracing_record_taskinfo'
kernel/trace/trace.c:2239: warning: Function parameter or member 'flags' not described in 'tracing_record_taskinfo'
kernel/trace/trace.c:2269: warning: Function parameter or member 'prev' not described in 'tracing_record_taskinfo_sched_switch'
kernel/trace/trace.c:2269: warning: Function parameter or member 'next' not described in 'tracing_record_taskinfo_sched_switch'
kernel/trace/trace.c:2269: warning: Function parameter or member 'flags' not described in 'tracing_record_taskinfo_sched_switch'
kernel/trace/trace.c:3078: warning: Function parameter or member 'ip' not described in 'trace_vbprintk'
kernel/trace/trace.c:3078: warning: Function parameter or member 'fmt' not described in 'trace_vbprintk'
kernel/trace/trace.c:3078: warning: Function parameter or member 'args' not described in 'trace_vbprintk'

Link: http://lkml.kernel.org/r/20190828052549.2472-2-jakub.kicinski@netronome.com

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 06:51:56 -04:00
Xinpeng Liu
19a58ce1dc tracing/probe: Fix null pointer dereference
BUG: KASAN: null-ptr-deref in trace_probe_cleanup+0x8d/0xd0
Read of size 8 at addr 0000000000000000 by task syz-executor.0/9746
trace_probe_cleanup+0x8d/0xd0
free_trace_kprobe.part.14+0x15/0x50
alloc_trace_kprobe+0x23e/0x250

Link: http://lkml.kernel.org/r/1565220563-980-1-git-send-email-danielliu861@gmail.com

Fixes: e3dc9f898e ("tracing/probe: Add trace_event_call accesses APIs")
Signed-off-by: Xinpeng Liu <danielliu861@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 06:51:55 -04:00
Denis Efremov
595a438c78 tracing: Make exported ftrace_set_clr_event non-static
The function ftrace_set_clr_event is declared static and marked
EXPORT_SYMBOL_GPL(), which is at best an odd combination. Because the
function was decided to be a part of API, this commit removes the static
attribute and adds the declaration to the header.

Link: http://lkml.kernel.org/r/20190704172110.27041-1-efremov@linux.com

Fixes: f45d1225ad ("tracing: Kernel access to Ftrace instances")
Reviewed-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-31 06:51:49 -04:00
Naveen N. Rao
5b0022dd32 ftrace: Check for successful allocation of hash
In register_ftrace_function_probe(), we are not checking the return
value of alloc_and_copy_ftrace_hash(). The subsequent call to
ftrace_match_records() may end up dereferencing the same. Add a check to
ensure this doesn't happen.

Link: http://lkml.kernel.org/r/26e92574f25ad23e7cafa3cf5f7a819de1832cbe.1562249521.git.naveen.n.rao@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: 1ec3a81a0c ("ftrace: Have each function probe use its own ftrace_ops")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-30 16:49:07 -04:00
Steven Rostedt (VMware)
372e0d01da ftrace: Check for empty hash and comment the race with registering probes
The race between adding a function probe and reading the probes that exist
is very subtle. It needs a comment. Also, the issue can also happen if the
probe has has the EMPTY_HASH as its func_hash.

Cc: stable@vger.kernel.org
Fixes: 7b60f3d876 ("ftrace: Dynamically create the probe ftrace_ops for the trace_array")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-30 16:30:01 -04:00
Naveen N. Rao
7bd46644ea ftrace: Fix NULL pointer dereference in t_probe_next()
LTP testsuite on powerpc results in the below crash:

  Unable to handle kernel paging request for data at address 0x00000000
  Faulting instruction address: 0xc00000000029d800
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE SMP NR_CPUS=2048 NUMA PowerNV
  ...
  CPU: 68 PID: 96584 Comm: cat Kdump: loaded Tainted: G        W
  NIP:  c00000000029d800 LR: c00000000029dac4 CTR: c0000000001e6ad0
  REGS: c0002017fae8ba10 TRAP: 0300   Tainted: G        W
  MSR:  9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE>  CR: 28022422  XER: 20040000
  CFAR: c00000000029d90c DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0
  ...
  NIP [c00000000029d800] t_probe_next+0x60/0x180
  LR [c00000000029dac4] t_mod_start+0x1a4/0x1f0
  Call Trace:
  [c0002017fae8bc90] [c000000000cdbc40] _cond_resched+0x10/0xb0 (unreliable)
  [c0002017fae8bce0] [c0000000002a15b0] t_start+0xf0/0x1c0
  [c0002017fae8bd30] [c0000000004ec2b4] seq_read+0x184/0x640
  [c0002017fae8bdd0] [c0000000004a57bc] sys_read+0x10c/0x300
  [c0002017fae8be30] [c00000000000b388] system_call+0x5c/0x70

The test (ftrace_set_ftrace_filter.sh) is part of ftrace stress tests
and the crash happens when the test does 'cat
$TRACING_PATH/set_ftrace_filter'.

The address points to the second line below, in t_probe_next(), where
filter_hash is dereferenced:
  hash = iter->probe->ops.func_hash->filter_hash;
  size = 1 << hash->size_bits;

This happens due to a race with register_ftrace_function_probe(). A new
ftrace_func_probe is created and added into the func_probes list in
trace_array under ftrace_lock. However, before initializing the filter,
we drop ftrace_lock, and re-acquire it after acquiring regex_lock. If
another process is trying to read set_ftrace_filter, it will be able to
acquire ftrace_lock during this window and it will end up seeing a NULL
filter_hash.

Fix this by just checking for a NULL filter_hash in t_probe_next(). If
the filter_hash is NULL, then this probe is just being added and we can
simply return from here.

Link: http://lkml.kernel.org/r/05e021f757625cbbb006fad41380323dbe4e3b43.1562249521.git.naveen.n.rao@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: 7b60f3d876 ("ftrace: Dynamically create the probe ftrace_ops for the trace_array")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-30 16:23:47 -04:00
Ingo Molnar
6c06b66e95 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU and LKMM changes from Paul E. McKenney:

 - A few more RCU flavor consolidation cleanups.

 - Miscellaneous fixes.

 - Updates to RCU's list-traversal macros improving lockdep usability.

 - Torture-test updates.

 - Forward-progress improvements for no-CBs CPUs: Avoid ignoring
   incoming callbacks during grace-period waits.

 - Forward-progress improvements for no-CBs CPUs: Use ->cblist
   structure to take advantage of others' grace periods.

 - Also added a small commit that avoids needlessly inflicting
   scheduler-clock ticks on callback-offloaded CPUs.

 - Forward-progress improvements for no-CBs CPUs: Reduce contention
   on ->nocb_lock guarding ->cblist.

 - Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
   list to further reduce contention on ->nocb_lock guarding ->cblist.

 - LKMM updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-22 20:52:04 +02:00
Peter Wu
5cbd22c179 bpf: clarify description for CONFIG_BPF_EVENTS
PERF_EVENT_IOC_SET_BPF supports uprobes since v4.3, and tracepoints
since v4.7 via commit 04a22fae4c ("tracing, perf: Implement BPF
programs attached to uprobes"), and commit 98b5c2c65c ("perf, bpf:
allow bpf programs attach to tracepoints") respectively.

Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-08-21 10:17:24 -07:00
David Howells
9d1f8be5cf bpf: Restrict bpf when kernel lockdown is in confidentiality mode
bpf_read() and bpf_read_str() could potentially be abused to (eg) allow
private keys in kernel memory to be leaked. Disable them if the kernel
has been locked down in confidentiality mode.

Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: netdev@vger.kernel.org
cc: Chun-Yi Lee <jlee@suse.com>
cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
David Howells
a94549dd87 lockdown: Lock down tracing and perf kprobes when in confidentiality mode
Disallow the creation of perf and ftrace kprobes when the kernel is
locked down in confidentiality mode by preventing their registration.
This prevents kprobes from being used to access kernel memory to steal
crypto data, but continues to allow the use of kprobes from signed
modules.

Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: davem@davemloft.net
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Joel Fernandes (Google)
0a5b99f578 treewide: Rename rcu_dereference_raw_notrace() to _check()
The rcu_dereference_raw_notrace() API name is confusing.  It is equivalent
to rcu_dereference_raw() except that it also does sparse pointer checking.

There are only a few users of rcu_dereference_raw_notrace(). This patches
renames all of them to be rcu_dereference_raw_check() with the "_check()"
indicating sparse checking.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Fix checkpatch warnings about parentheses. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-08-01 14:16:21 -07:00
Thomas Gleixner
30c937043b tracing: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.

Switch the conditionals in the tracer over to CONFIG_PREEMPTION.

This is the first step to make the tracer work on RT. The other small
tweaks are submitted separately.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.409766323@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-31 19:03:35 +02:00
Thomas Gleixner
01b1d88b09 rcu: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.

Switch the conditionals in RCU to use CONFIG_PREEMPTION.

That's the first step towards RCU on RT. The further tweaks are work in
progress. This neither touches the selftest bits which need a closer look
by Paul.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.210156346@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-31 19:03:35 +02:00
Changbin Du
6c77221df9 fgraph: Remove redundant ftrace_graph_notrace_addr() test
We already have tested it before. The second one should be removed.
With this change, the performance should have little improvement.

Link: http://lkml.kernel.org/r/20190730140850.7927-1-changbin.du@gmail.com

Cc: stable@vger.kernel.org
Fixes: 9cd2992f2d ("fgraph: Have set_graph_notrace only affect function_graph tracer")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-30 21:50:03 -04:00
Matthew Wilcox (Oracle)
7b3c92b85a sched/core: Convert get_task_struct() to return the task
Returning the pointer that was passed in allows us to write
slightly more idiomatic code.  Convert a few users.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190704221323.24290-1-willy@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:51:54 +02:00
Linus Torvalds
41ba485ef1 Eiichi Tsukata found a small bug from the fixup of the stack code
Removing ULONG_MAX as the marker for the user stack trace end,
 made the tracing code not know where the end is. The end is now
 marked with a zero (NULL) pointer. Eiichi fixed this in the tracing
 code.
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Merge tag 'trace-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Eiichi Tsukata found a small bug from the fixup of the stack code

  Removing ULONG_MAX as the marker for the user stack trace end, made
  the tracing code not know where the end is. The end is now marked with
  a zero (NULL) pointer. Eiichi fixed this in the tracing code"

* tag 'trace-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix user stack trace "??" output
2019-07-19 12:18:46 -07:00
Eiichi Tsukata
6d54ceb539 tracing: Fix user stack trace "??" output
Commit c5c27a0a58 ("x86/stacktrace: Remove the pointless ULONG_MAX
marker") removes ULONG_MAX marker from user stack trace entries but
trace_user_stack_print() still uses the marker and it outputs unnecessary
"??".

For example:

            less-1911  [001] d..2    34.758944: <user stack trace>
   =>  <00007f16f2295910>
   => ??
   => ??
   => ??
   => ??
   => ??
   => ??
   => ??

The user stack trace code zeroes the storage before saving the stack, so if
the trace is shorter than the maximum number of entries it can terminate
the print loop if a zero entry is detected.

Link: http://lkml.kernel.org/r/20190630085438.25545-1-devel@etsukata.com

Cc: stable@vger.kernel.org
Fixes: 4285f2fcef ("tracing: Remove the ULONG_MAX stack trace hackery")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-19 12:12:39 -04:00
Linus Torvalds
818e95c768 The main changes in this release include:
- Add user space specific memory reading for kprobes
  - Allow kprobes to be executed earlier in boot
 
 The rest are mostly just various clean ups and small fixes.
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Merge tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The main changes in this release include:

   - Add user space specific memory reading for kprobes

   - Allow kprobes to be executed earlier in boot

  The rest are mostly just various clean ups and small fixes"

* tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
  tracing: Make trace_get_fields() global
  tracing: Let filter_assign_type() detect FILTER_PTR_STRING
  tracing: Pass type into tracing_generic_entry_update()
  ftrace/selftest: Test if set_event/ftrace_pid exists before writing
  ftrace/selftests: Return the skip code when tracing directory not configured in kernel
  tracing/kprobe: Check registered state using kprobe
  tracing/probe: Add trace_event_call accesses APIs
  tracing/probe: Add probe event name and group name accesses APIs
  tracing/probe: Add trace flag access APIs for trace_probe
  tracing/probe: Add trace_event_file access APIs for trace_probe
  tracing/probe: Add trace_event_call register API for trace_probe
  tracing/probe: Add trace_probe init and free functions
  tracing/uprobe: Set print format when parsing command
  tracing/kprobe: Set print format right after parsed command
  kprobes: Fix to init kprobes in subsys_initcall
  tracepoint: Use struct_size() in kmalloc()
  ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS
  ftrace: Enable trampoline when rec count returns back to one
  tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline
  tracing: Make a separate config for trace event self tests
  ...
2019-07-18 11:51:00 -07:00
Cong Wang
0aeb1def44 tracing: Make trace_get_fields() global
trace_get_fields() is the only way to read tracepoint fields at
run time, as their fields are defined at compile-time with macros.
Make this function visible to all users and it will be used by
trace event injection code to calculate the size of a tracepoint
entry.
Link: http://lkml.kernel.org/r/20190525165802.25944-4-xiyou.wangcong@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:48 -04:00
Cong Wang
5967bd5c42 tracing: Let filter_assign_type() detect FILTER_PTR_STRING
filter_assign_type() could detect dynamic string and static
string, but not string pointers. Teach filter_assign_type()
to detect string pointers, and this will be needed by trace
event injection code.

BTW, trace event hist uses FILTER_PTR_STRING too.
Link: http://lkml.kernel.org/r/20190525165802.25944-3-xiyou.wangcong@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:48 -04:00
Cong Wang
46710f3a34 tracing: Pass type into tracing_generic_entry_update()
All callers of tracing_generic_entry_update() have to initialize
entry->type, so let's just simply move it inside.
Link: http://lkml.kernel.org/r/20190525165802.25944-2-xiyou.wangcong@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:48 -04:00
Masami Hiramatsu
715fa2fd4c tracing/kprobe: Check registered state using kprobe
Change registered check only by trace_kprobe and remove
TP_FLAG_REGISTERED from trace_probe, since this feature
is only used for trace_kprobe.

Link: http://lkml.kernel.org/r/155931588704.28323.4952266828256245833.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
e3dc9f898e tracing/probe: Add trace_event_call accesses APIs
Add trace_event_call access APIs for trace_probe.
Instead of accessing trace_probe.call directly, use those
accesses by trace_probe_event_call() method. This hides
the relationship of trace_event_call and trace_probe from
trace_kprobe and trace_uprobe.

Link: http://lkml.kernel.org/r/155931587711.28323.8335129014686133120.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
b55ce203a8 tracing/probe: Add probe event name and group name accesses APIs
Add trace_probe_name() and trace_probe_group_name() functions
for accessing probe name and group name of trace_probe.

Link: http://lkml.kernel.org/r/155931586717.28323.8738615064952254761.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
747774d6b0 tracing/probe: Add trace flag access APIs for trace_probe
Add trace_probe_test/set/clear_flag() functions for accessing
trace_probe.flag field.
This flags field should not be accessed directly.

Link: http://lkml.kernel.org/r/155931585683.28323.314290023236905988.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
b5f935ee13 tracing/probe: Add trace_event_file access APIs for trace_probe
Add trace_event_file access APIs for trace_probe data structure.
This simplifies enabling/disabling operations in uprobe and kprobe
events so that those don't touch deep inside the trace_probe.

This also removing a redundant synchronization when the
kprobe event is used from perf, since the perf itself uses
tracepoint_synchronize_unregister() after disabling (ftrace-
defined) event, thus we don't have to synchronize in that
path. Also we don't need to identify local trace_kprobe too
anymore.

Link: http://lkml.kernel.org/r/155931584587.28323.372301976283354629.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
46e5376d40 tracing/probe: Add trace_event_call register API for trace_probe
Since trace_event_call is a field of trace_probe, these
operations should be done in trace_probe.c. trace_kprobe
and trace_uprobe use new functions to register/unregister
trace_event_call.

Link: http://lkml.kernel.org/r/155931583643.28323.14828411185591538876.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
455b289973 tracing/probe: Add trace_probe init and free functions
Add common trace_probe init and cleanup function in
trace_probe.c, and use it from trace_kprobe.c and trace_uprobe.c

Link: http://lkml.kernel.org/r/155931582664.28323.5934870189034740822.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
b4d4b96be8 tracing/uprobe: Set print format when parsing command
Set event call's print format right after parsed command for
simplifying (un)register_uprobe_event().

Link: http://lkml.kernel.org/r/155931581659.28323.5404667166417404076.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Masami Hiramatsu
f730e0f2da tracing/kprobe: Set print format right after parsed command
Set event call's print format right after parsed command for
simplifying (un)register_kprobe_event().

Link: http://lkml.kernel.org/r/155931580625.28323.5158822928646225903.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16 15:14:47 -04:00
Linus Torvalds
f632a8170a Driver Core and debugfs changes for 5.3-rc1
Here is the "big" driver core and debugfs changes for 5.3-rc1
 
 It's a lot of different patches, all across the tree due to some api
 changes and lots of debugfs cleanups.  Because of this, there is going
 to be some merge issues with your tree at the moment, I'll follow up
 with the expected resolutions to make it easier for you.
 
 Other than the debugfs cleanups, in this set of changes we have:
 	- bus iteration function cleanups (will cause build warnings
 	  with s390 and coresight drivers in your tree)
 	- scripts/get_abi.pl tool to display and parse Documentation/ABI
 	  entries in a simple way
 	- cleanups to Documenatation/ABI/ entries to make them parse
 	  easier due to typos and other minor things
 	- default_attrs use for some ktype users
 	- driver model documentation file conversions to .rst
 	- compressed firmware file loading
 	- deferred probe fixes
 
 All of these have been in linux-next for a while, with a bunch of merge
 issues that Stephen has been patient with me for.  Other than the merge
 issues, functionality is working properly in linux-next :)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...
2019-07-12 12:24:03 -07:00
Linus Torvalds
237f83dfbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
2019-07-11 10:55:49 -07:00
Linus Torvalds
608745f124 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main changes in this cycle on the kernel side were:

   - CPU PMU and uncore driver updates to Intel Snow Ridge, IceLake,
     KabyLake, AmberLake and WhiskeyLake CPUs.

   - Rework the MSR probing infrastructure to make it more robust, make
     it work better on virtualized systems and to better expose it on
     sysfs.

   - Rework PMU attributes group support based on the feedback from
     Greg. The core sysfs patch that adds sysfs_update_groups() was
     acked by Greg.

  There's a lot of perf tooling changes as well, all around the place:

   - vendor updates to Intel, cs-etm (ARM), ARM64, s390,

   - various enhancements to Intel PT tooling support:
      - Improve CBR (Core to Bus Ratio) packets support.
      - Export power and ptwrite events to sqlite and postgresql.
      - Add support for decoding PEBS via PT packets.
      - Add support for samples to contain IPC ratio, collecting cycles
        information from CYC packets, showing the IPC info periodically
      - Allow using time ranges

   - lots of updates to perf pmu, perf stat, perf trace, eBPF support,
     perf record, perf diff, etc. - please see the shortlog and Git log
     for details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (252 commits)
  tools arch x86: Sync asm/cpufeatures.h with the with the kernel
  tools build: Check if gettid() is available before providing helper
  perf jvmti: Address gcc string overflow warning for strncpy()
  perf python: Remove -fstack-protector-strong if clang doesn't have it
  perf annotate TUI browser: Do not use member from variable within its own initialization
  perf tests: Fix record+probe_libc_inet_pton.sh for powerpc64
  perf evsel: Do not rely on errno values for precise_ip fallback
  perf thread: Allow references to thread objects after machine__exit()
  perf header: Assign proper ff->ph in perf_event__synthesize_features()
  tools arch kvm: Sync kvm headers with the kernel sources
  perf script: Allow specifying the files to process guest samples
  perf tools metric: Don't include duration_time in group
  perf list: Avoid extra : for --raw metrics
  perf vendor events intel: Metric fixes for SKX/CLX
  perf tools: Fix typos / broken sentences
  perf jevents: Add support for Hisi hip08 L3C PMU aliasing
  perf jevents: Add support for Hisi hip08 HHA PMU aliasing
  perf jevents: Add support for Hisi hip08 DDRC PMU aliasing
  perf pmu: Support more complex PMU event aliasing
  perf diff: Documentation -c cycles option
  ...
2019-07-09 11:15:52 -07:00
Linus Torvalds
dad1c12ed8 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - Remove the unused per rq load array and all its infrastructure, by
   Dietmar Eggemann.

 - Add utilization clamping support by Patrick Bellasi. This is a
   refinement of the energy aware scheduling framework with support for
   boosting of interactive and capping of background workloads: to make
   sure critical GUI threads get maximum frequency ASAP, and to make
   sure background processing doesn't unnecessarily move to cpufreq
   governor to higher frequencies and less energy efficient CPU modes.

 - Add the bare minimum of tracepoints required for LISA EAS regression
   testing, by Qais Yousef - which allows automated testing of various
   power management features, including energy aware scheduling.

 - Restructure the former tsk_nr_cpus_allowed() facility that the -rt
   kernel used to modify the scheduler's CPU affinity logic such as
   migrate_disable() - introduce the task->cpus_ptr value instead of
   taking the address of &task->cpus_allowed directly - by Sebastian
   Andrzej Siewior.

 - Misc optimizations, fixes, cleanups and small enhancements - see the
   Git log for details.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  sched/uclamp: Add uclamp support to energy_compute()
  sched/uclamp: Add uclamp_util_with()
  sched/cpufreq, sched/uclamp: Add clamps for FAIR and RT tasks
  sched/uclamp: Set default clamps for RT tasks
  sched/uclamp: Reset uclamp values on RESET_ON_FORK
  sched/uclamp: Extend sched_setattr() to support utilization clamping
  sched/core: Allow sched_setattr() to use the current policy
  sched/uclamp: Add system default clamps
  sched/uclamp: Enforce last task's UCLAMP_MAX
  sched/uclamp: Add bucket local max tracking
  sched/uclamp: Add CPU's clamp buckets refcounting
  sched/fair: Rename weighted_cpuload() to cpu_runnable_load()
  sched/debug: Export the newly added tracepoints
  sched/debug: Add sched_overutilized tracepoint
  sched/debug: Add new tracepoint to track PELT at se level
  sched/debug: Add new tracepoints to track PELT at rq level
  sched/debug: Add a new sched_trace_*() helper functions
  sched/autogroup: Make autogroup_path() always available
  sched/wait: Deduplicate code with do-while
  sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity()
  ...
2019-07-08 16:39:53 -07:00
Ingo Molnar
552a031ba1 Linux 5.2
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Merge tag 'v5.2' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-08 18:04:41 +02:00
Linus Torvalds
550d1f5bda This includes three fixes:
- Fixes a deadlock from a previous fix to keep module loading
    and function tracing text modifications from stepping on each other.
    (this has a few patches to help document the issue in comments)
 
  - Fix a crash when the snapshot buffer gets out of sync with the
    main ring buffer.
 
  - Fix a memory leak when reading the memory logs
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Merge tag 'trace-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This includes three fixes:

   - Fix a deadlock from a previous fix to keep module loading and
     function tracing text modifications from stepping on each other
     (this has a few patches to help document the issue in comments)

   - Fix a crash when the snapshot buffer gets out of sync with the main
     ring buffer

   - Fix a memory leak when reading the memory logs"

* tag 'trace-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process() and ftrace_arch_code_modify_prepare()
  tracing/snapshot: Resize spare buffer if size changed
  tracing: Fix memory leak in tracing_err_log_open()
  ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()
  ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()
2019-07-04 10:26:17 +09:00
Eiichi Tsukata
46cc0b4442 tracing/snapshot: Resize spare buffer if size changed
Current snapshot implementation swaps two ring_buffers even though their
sizes are different from each other, that can cause an inconsistency
between the contents of buffer_size_kb file and the current buffer size.

For example:

  # cat buffer_size_kb
  7 (expanded: 1408)
  # echo 1 > events/enable
  # grep bytes per_cpu/cpu0/stats
  bytes: 1441020
  # echo 1 > snapshot             // current:1408, spare:1408
  # echo 123 > buffer_size_kb     // current:123,  spare:1408
  # echo 1 > snapshot             // current:1408, spare:123
  # grep bytes per_cpu/cpu0/stats
  bytes: 1443700
  # cat buffer_size_kb
  123                             // != current:1408

And also, a similar per-cpu case hits the following WARNING:

Reproducer:

  # echo 1 > per_cpu/cpu0/snapshot
  # echo 123 > buffer_size_kb
  # echo 1 > per_cpu/cpu0/snapshot

WARNING:

  WARNING: CPU: 0 PID: 1946 at kernel/trace/trace.c:1607 update_max_tr_single.part.0+0x2b8/0x380
  Modules linked in:
  CPU: 0 PID: 1946 Comm: bash Not tainted 5.2.0-rc6 #20
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014
  RIP: 0010:update_max_tr_single.part.0+0x2b8/0x380
  Code: ff e8 dc da f9 ff 0f 0b e9 88 fe ff ff e8 d0 da f9 ff 44 89 ee bf f5 ff ff ff e8 33 dc f9 ff 41 83 fd f5 74 96 e8 b8 da f9 ff <0f> 0b eb 8d e8 af da f9 ff 0f 0b e9 bf fd ff ff e8 a3 da f9 ff 48
  RSP: 0018:ffff888063e4fca0 EFLAGS: 00010093
  RAX: ffff888066214380 RBX: ffffffff99850fe0 RCX: ffffffff964298a8
  RDX: 0000000000000000 RSI: 00000000fffffff5 RDI: 0000000000000005
  RBP: 1ffff1100c7c9f96 R08: ffff888066214380 R09: ffffed100c7c9f9b
  R10: ffffed100c7c9f9a R11: 0000000000000003 R12: 0000000000000000
  R13: 00000000ffffffea R14: ffff888066214380 R15: ffffffff99851060
  FS:  00007f9f8173c700(0000) GS:ffff88806d000000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000714dc0 CR3: 0000000066fa6000 CR4: 00000000000006f0
  Call Trace:
   ? trace_array_printk_buf+0x140/0x140
   ? __mutex_lock_slowpath+0x10/0x10
   tracing_snapshot_write+0x4c8/0x7f0
   ? trace_printk_init_buffers+0x60/0x60
   ? selinux_file_permission+0x3b/0x540
   ? tracer_preempt_off+0x38/0x506
   ? trace_printk_init_buffers+0x60/0x60
   __vfs_write+0x81/0x100
   vfs_write+0x1e1/0x560
   ksys_write+0x126/0x250
   ? __ia32_sys_read+0xb0/0xb0
   ? do_syscall_64+0x1f/0x390
   do_syscall_64+0xc1/0x390
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

This patch adds resize_buffer_duplicate_size() to check if there is a
difference between current/spare buffer sizes and resize a spare buffer
if necessary.

Link: http://lkml.kernel.org/r/20190625012910.13109-1-devel@etsukata.com

Cc: stable@vger.kernel.org
Fixes: ad909e21bb ("tracing: Add internal tracing_snapshot() functions")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-28 14:58:52 -04:00
Takeshi Misawa
d122ed6288 tracing: Fix memory leak in tracing_err_log_open()
When tracing_err_log_open() calls seq_open(), allocated memory is not freed.

kmemleak report:

unreferenced object 0xffff92c0781d1100 (size 128):
  comm "tail", pid 15116, jiffies 4295163855 (age 22.704s)
  hex dump (first 32 bytes):
    00 f0 08 e5 c0 92 ff ff 00 10 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<000000000d0687d5>] kmem_cache_alloc+0x11f/0x1e0
    [<000000003e3039a8>] seq_open+0x2f/0x90
    [<000000008dd36b7d>] tracing_err_log_open+0x67/0x140
    [<000000005a431ae2>] do_dentry_open+0x1df/0x3a0
    [<00000000a2910603>] vfs_open+0x2f/0x40
    [<0000000038b0a383>] path_openat+0x2e8/0x1690
    [<00000000fe025bda>] do_filp_open+0x9b/0x110
    [<00000000483a5091>] do_sys_open+0x1ba/0x260
    [<00000000c558b5fd>] __x64_sys_openat+0x20/0x30
    [<000000006881ec07>] do_syscall_64+0x5a/0x130
    [<00000000571c2e94>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix this by calling seq_release() in tracing_err_log_fops.release().

Link: http://lkml.kernel.org/r/20190628105640.GA1863@DESKTOP

Fixes: 8a062902be ("tracing: Add tracing error log")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Takeshi Misawa <jeliantsurux@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-28 14:57:23 -04:00
Petr Mladek
d5b844a2cf ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()
The commit 9f255b632b ("module: Fix livepatch/ftrace module text
permissions race") causes a possible deadlock between register_kprobe()
and ftrace_run_update_code() when ftrace is using stop_machine().

The existing dependency chain (in reverse order) is:

-> #1 (text_mutex){+.+.}:
       validate_chain.isra.21+0xb32/0xd70
       __lock_acquire+0x4b8/0x928
       lock_acquire+0x102/0x230
       __mutex_lock+0x88/0x908
       mutex_lock_nested+0x32/0x40
       register_kprobe+0x254/0x658
       init_kprobes+0x11a/0x168
       do_one_initcall+0x70/0x318
       kernel_init_freeable+0x456/0x508
       kernel_init+0x22/0x150
       ret_from_fork+0x30/0x34
       kernel_thread_starter+0x0/0xc

-> #0 (cpu_hotplug_lock.rw_sem){++++}:
       check_prev_add+0x90c/0xde0
       validate_chain.isra.21+0xb32/0xd70
       __lock_acquire+0x4b8/0x928
       lock_acquire+0x102/0x230
       cpus_read_lock+0x62/0xd0
       stop_machine+0x2e/0x60
       arch_ftrace_update_code+0x2e/0x40
       ftrace_run_update_code+0x40/0xa0
       ftrace_startup+0xb2/0x168
       register_ftrace_function+0x64/0x88
       klp_patch_object+0x1a2/0x290
       klp_enable_patch+0x554/0x980
       do_one_initcall+0x70/0x318
       do_init_module+0x6e/0x250
       load_module+0x1782/0x1990
       __s390x_sys_finit_module+0xaa/0xf0
       system_call+0xd8/0x2d0

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(text_mutex);
                               lock(cpu_hotplug_lock.rw_sem);
                               lock(text_mutex);
  lock(cpu_hotplug_lock.rw_sem);

It is similar problem that has been solved by the commit 2d1e38f566
("kprobes: Cure hotplug lock ordering issues"). Many locks are involved.
To be on the safe side, text_mutex must become a low level lock taken
after cpu_hotplug_lock.rw_sem.

This can't be achieved easily with the current ftrace design.
For example, arm calls set_all_modules_text_rw() already in
ftrace_arch_code_modify_prepare(), see arch/arm/kernel/ftrace.c.
This functions is called:

  + outside stop_machine() from ftrace_run_update_code()
  + without stop_machine() from ftrace_module_enable()

Fortunately, the problematic fix is needed only on x86_64. It is
the only architecture that calls set_all_modules_text_rw()
in ftrace path and supports livepatching at the same time.

Therefore it is enough to move text_mutex handling from the generic
kernel/trace/ftrace.c into arch/x86/kernel/ftrace.c:

   ftrace_arch_code_modify_prepare()
   ftrace_arch_code_modify_post_process()

This patch basically reverts the ftrace part of the problematic
commit 9f255b632b ("module: Fix livepatch/ftrace module
text permissions race"). And provides x86_64 specific-fix.

Some refactoring of the ftrace code will be needed when livepatching
is implemented for arm or nds32. These architectures call
set_all_modules_text_rw() and use stop_machine() at the same time.

Link: http://lkml.kernel.org/r/20190627081334.12793-1-pmladek@suse.com

Fixes: 9f255b632b ("module: Fix livepatch/ftrace module text permissions race")
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
[
  As reviewed by Miroslav Benes <mbenes@suse.cz>, removed return value of
  ftrace_run_update_code() as it is a void function.
]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-28 14:20:25 -04:00
Yonghong Song
9db1ff0a41 bpf: fix compiler warning with CONFIG_MODULES=n
With CONFIG_MODULES=n, the following compiler warning occurs:
  /data/users/yhs/work/net-next/kernel/trace/bpf_trace.c:605:13: warning:
      ‘do_bpf_send_signal’ defined but not used [-Wunused-function]
  static void do_bpf_send_signal(struct irq_work *entry)

The __init function send_signal_irq_work_init(), which calls
do_bpf_send_signal(), is defined under CONFIG_MODULES. Hence,
when CONFIG_MODULES=n, nobody calls static function do_bpf_send_signal(),
hence the warning.

The init function send_signal_irq_work_init() should work without
CONFIG_MODULES. Moving it out of CONFIG_MODULES
code section fixed the compiler warning, and also make bpf_send_signal()
helper work without CONFIG_MODULES.

Fixes: 8b401f9ed2 ("bpf: implement bpf_send_signal() helper")
Reported-By: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-26 14:44:07 +02:00
Ingo Molnar
b9271f0c65 Linux 5.2-rc6
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Merge tag 'v5.2-rc6' into perf/core, to refresh branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24 19:25:52 +02:00
Ingo Molnar
d2abae71eb Linux 5.2-rc6
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Merge tag 'v5.2-rc6' into sched/core, to refresh the branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24 19:19:53 +02:00
David S. Miller
13091aa305 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Honestly all the conflicts were simple overlapping changes,
nothing really interesting to report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-17 20:20:36 -07:00
Linus Torvalds
da0f382029 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Lots of bug fixes here:

   1) Out of bounds access in __bpf_skc_lookup, from Lorenz Bauer.

   2) Fix rate reporting in cfg80211_calculate_bitrate_he(), from John
      Crispin.

   3) Use after free in psock backlog workqueue, from John Fastabend.

   4) Fix source port matching in fdb peer flow rule of mlx5, from Raed
      Salem.

   5) Use atomic_inc_not_zero() in fl6_sock_lookup(), from Eric Dumazet.

   6) Network header needs to be set for packet redirect in nfp, from
      John Hurley.

   7) Fix udp zerocopy refcnt, from Willem de Bruijn.

   8) Don't assume linear buffers in vxlan and geneve error handlers,
      from Stefano Brivio.

   9) Fix TOS matching in mlxsw, from Jiri Pirko.

  10) More SCTP cookie memory leak fixes, from Neil Horman.

  11) Fix VLAN filtering in rtl8366, from Linus Walluij.

  12) Various TCP SACK payload size and fragmentation memory limit fixes
      from Eric Dumazet.

  13) Use after free in pneigh_get_next(), also from Eric Dumazet.

  14) LAPB control block leak fix from Jeremy Sowden"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (145 commits)
  lapb: fixed leak of control-blocks.
  tipc: purge deferredq list for each grp member in tipc_group_delete
  ax25: fix inconsistent lock state in ax25_destroy_timer
  neigh: fix use-after-free read in pneigh_get_next
  tcp: fix compile error if !CONFIG_SYSCTL
  hv_sock: Suppress bogus "may be used uninitialized" warnings
  be2net: Fix number of Rx queues used for flow hashing
  net: handle 802.1P vlan 0 packets properly
  tcp: enforce tcp_min_snd_mss in tcp_mtu_probing()
  tcp: add tcp_min_snd_mss sysctl
  tcp: tcp_fragment() should apply sane memory limits
  tcp: limit payload size of sacked skbs
  Revert "net: phylink: set the autoneg state in phylink_phy_change"
  bpf: fix nested bpf tracepoints with per-cpu data
  bpf: Fix out of bounds memory access in bpf_sk_storage
  vsock/virtio: set SOCK_DONE on peer shutdown
  net: dsa: rtl8366: Fix up VLAN filtering
  net: phylink: set the autoneg state in phylink_phy_change
  net: add high_order_alloc_disable sysctl/static key
  tcp: add tcp_tx_skb_cache sysctl
  ...
2019-06-17 15:55:34 -07:00
Ingo Molnar
23da766ab1 Linux 5.2-rc5
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Merge tag 'v5.2-rc5' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:12:27 +02:00
Matt Mullins
9594dc3c7e bpf: fix nested bpf tracepoints with per-cpu data
BPF_PROG_TYPE_RAW_TRACEPOINTs can be executed nested on the same CPU, as
they do not increment bpf_prog_active while executing.

This enables three levels of nesting, to support
  - a kprobe or raw tp or perf event,
  - another one of the above that irq context happens to call, and
  - another one in nmi context
(at most one of which may be a kprobe or perf event).

Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Signed-off-by: Matt Mullins <mmullins@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-06-15 16:33:35 -07:00
Linus Torvalds
6a71398c6a This includes the following fixes:
- Out of range read of stack trace output
  - Fix for NULL pointer dereference in trace_uprobe_create()
  - Fix to a livepatching / ftrace permission race in the module code
  - Fix for NULL pointer dereference in free_ftrace_func_mapper()
  - A couple of build warning clean ups
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Merge tag 'trace-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Out of range read of stack trace output

 - Fix for NULL pointer dereference in trace_uprobe_create()

 - Fix to a livepatching / ftrace permission race in the module code

 - Fix for NULL pointer dereference in free_ftrace_func_mapper()

 - A couple of build warning clean ups

* tag 'trace-v5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Fix NULL pointer dereference in free_ftrace_func_mapper()
  module: Fix livepatch/ftrace module text permissions race
  tracing/uprobe: Fix obsolete comment on trace_uprobe_create()
  tracing/uprobe: Fix NULL pointer dereference in trace_uprobe_create()
  tracing: Make two symbols static
  tracing: avoid build warning with HAVE_NOP_MCOUNT
  tracing: Fix out-of-range read in trace_stack_print()
2019-06-15 07:24:11 -10:00
Wei Li
04e03d9a61 ftrace: Fix NULL pointer dereference in free_ftrace_func_mapper()
The mapper may be NULL when called from register_ftrace_function_probe()
with probe->data == NULL.

This issue can be reproduced as follow (it may be covered by compiler
optimization sometime):

/ # cat /sys/kernel/debug/tracing/set_ftrace_filter
#### all functions enabled ####
/ # echo foo_bar:dump > /sys/kernel/debug/tracing/set_ftrace_filter
[  206.949100] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[  206.952402] Mem abort info:
[  206.952819]   ESR = 0x96000006
[  206.955326]   Exception class = DABT (current EL), IL = 32 bits
[  206.955844]   SET = 0, FnV = 0
[  206.956272]   EA = 0, S1PTW = 0
[  206.956652] Data abort info:
[  206.957320]   ISV = 0, ISS = 0x00000006
[  206.959271]   CM = 0, WnR = 0
[  206.959938] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000419f3a000
[  206.960483] [0000000000000000] pgd=0000000411a87003, pud=0000000411a83003, pmd=0000000000000000
[  206.964953] Internal error: Oops: 96000006 [#1] SMP
[  206.971122] Dumping ftrace buffer:
[  206.973677]    (ftrace buffer empty)
[  206.975258] Modules linked in:
[  206.976631] Process sh (pid: 281, stack limit = 0x(____ptrval____))
[  206.978449] CPU: 10 PID: 281 Comm: sh Not tainted 5.2.0-rc1+ #17
[  206.978955] Hardware name: linux,dummy-virt (DT)
[  206.979883] pstate: 60000005 (nZCv daif -PAN -UAO)
[  206.980499] pc : free_ftrace_func_mapper+0x2c/0x118
[  206.980874] lr : ftrace_count_free+0x68/0x80
[  206.982539] sp : ffff0000182f3ab0
[  206.983102] x29: ffff0000182f3ab0 x28: ffff8003d0ec1700
[  206.983632] x27: ffff000013054b40 x26: 0000000000000001
[  206.984000] x25: ffff00001385f000 x24: 0000000000000000
[  206.984394] x23: ffff000013453000 x22: ffff000013054000
[  206.984775] x21: 0000000000000000 x20: ffff00001385fe28
[  206.986575] x19: ffff000013872c30 x18: 0000000000000000
[  206.987111] x17: 0000000000000000 x16: 0000000000000000
[  206.987491] x15: ffffffffffffffb0 x14: 0000000000000000
[  206.987850] x13: 000000000017430e x12: 0000000000000580
[  206.988251] x11: 0000000000000000 x10: cccccccccccccccc
[  206.988740] x9 : 0000000000000000 x8 : ffff000013917550
[  206.990198] x7 : ffff000012fac2e8 x6 : ffff000012fac000
[  206.991008] x5 : ffff0000103da588 x4 : 0000000000000001
[  206.991395] x3 : 0000000000000001 x2 : ffff000013872a28
[  206.991771] x1 : 0000000000000000 x0 : 0000000000000000
[  206.992557] Call trace:
[  206.993101]  free_ftrace_func_mapper+0x2c/0x118
[  206.994827]  ftrace_count_free+0x68/0x80
[  206.995238]  release_probe+0xfc/0x1d0
[  206.995555]  register_ftrace_function_probe+0x4a8/0x868
[  206.995923]  ftrace_trace_probe_callback.isra.4+0xb8/0x180
[  206.996330]  ftrace_dump_callback+0x50/0x70
[  206.996663]  ftrace_regex_write.isra.29+0x290/0x3a8
[  206.997157]  ftrace_filter_write+0x44/0x60
[  206.998971]  __vfs_write+0x64/0xf0
[  206.999285]  vfs_write+0x14c/0x2f0
[  206.999591]  ksys_write+0xbc/0x1b0
[  206.999888]  __arm64_sys_write+0x3c/0x58
[  207.000246]  el0_svc_common.constprop.0+0x408/0x5f0
[  207.000607]  el0_svc_handler+0x144/0x1c8
[  207.000916]  el0_svc+0x8/0xc
[  207.003699] Code: aa0003f8 a9025bf5 aa0103f5 f946ea80 (f9400303)
[  207.008388] ---[ end trace 7b6d11b5f542bdf1 ]---
[  207.010126] Kernel panic - not syncing: Fatal exception
[  207.011322] SMP: stopping secondary CPUs
[  207.013956] Dumping ftrace buffer:
[  207.014595]    (ftrace buffer empty)
[  207.015632] Kernel Offset: disabled
[  207.017187] CPU features: 0x002,20006008
[  207.017985] Memory Limit: none
[  207.019825] ---[ end Kernel panic - not syncing: Fatal exception ]---

Link: http://lkml.kernel.org/r/20190606031754.10798-1-liwei391@huawei.com

Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 17:40:21 -04:00
Josh Poimboeuf
9f255b632b module: Fix livepatch/ftrace module text permissions race
It's possible for livepatch and ftrace to be toggling a module's text
permissions at the same time, resulting in the following panic:

  BUG: unable to handle page fault for address: ffffffffc005b1d9
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0003) - permissions violation
  PGD 3ea0c067 P4D 3ea0c067 PUD 3ea0e067 PMD 3cc13067 PTE 3b8a1061
  Oops: 0003 [#1] PREEMPT SMP PTI
  CPU: 1 PID: 453 Comm: insmod Tainted: G           O  K   5.2.0-rc1-a188339ca5 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014
  RIP: 0010:apply_relocate_add+0xbe/0x14c
  Code: fa 0b 74 21 48 83 fa 18 74 38 48 83 fa 0a 75 40 eb 08 48 83 38 00 74 33 eb 53 83 38 00 75 4e 89 08 89 c8 eb 0a 83 38 00 75 43 <89> 08 48 63 c1 48 39 c8 74 2e eb 48 83 38 00 75 32 48 29 c1 89 08
  RSP: 0018:ffffb223c00dbb10 EFLAGS: 00010246
  RAX: ffffffffc005b1d9 RBX: 0000000000000000 RCX: ffffffff8b200060
  RDX: 000000000000000b RSI: 0000004b0000000b RDI: ffff96bdfcd33000
  RBP: ffffb223c00dbb38 R08: ffffffffc005d040 R09: ffffffffc005c1f0
  R10: ffff96bdfcd33c40 R11: ffff96bdfcd33b80 R12: 0000000000000018
  R13: ffffffffc005c1f0 R14: ffffffffc005e708 R15: ffffffff8b2fbc74
  FS:  00007f5f447beba8(0000) GS:ffff96bdff900000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffffffc005b1d9 CR3: 000000003cedc002 CR4: 0000000000360ea0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   klp_init_object_loaded+0x10f/0x219
   ? preempt_latency_start+0x21/0x57
   klp_enable_patch+0x662/0x809
   ? virt_to_head_page+0x3a/0x3c
   ? kfree+0x8c/0x126
   patch_init+0x2ed/0x1000 [livepatch_test02]
   ? 0xffffffffc0060000
   do_one_initcall+0x9f/0x1c5
   ? kmem_cache_alloc_trace+0xc4/0xd4
   ? do_init_module+0x27/0x210
   do_init_module+0x5f/0x210
   load_module+0x1c41/0x2290
   ? fsnotify_path+0x3b/0x42
   ? strstarts+0x2b/0x2b
   ? kernel_read+0x58/0x65
   __do_sys_finit_module+0x9f/0xc3
   ? __do_sys_finit_module+0x9f/0xc3
   __x64_sys_finit_module+0x1a/0x1c
   do_syscall_64+0x52/0x61
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

The above panic occurs when loading two modules at the same time with
ftrace enabled, where at least one of the modules is a livepatch module:

CPU0					CPU1
klp_enable_patch()
  klp_init_object_loaded()
    module_disable_ro()
    					ftrace_module_enable()
					  ftrace_arch_code_modify_post_process()
				    	    set_all_modules_text_ro()
      klp_write_object_relocations()
        apply_relocate_add()
	  *patches read-only code* - BOOM

A similar race exists when toggling ftrace while loading a livepatch
module.

Fix it by ensuring that the livepatch and ftrace code patching
operations -- and their respective permissions changes -- are protected
by the text_mutex.

Link: http://lkml.kernel.org/r/ab43d56ab909469ac5d2520c5d944ad6d4abd476.1560474114.git.jpoimboe@redhat.com

Reported-by: Johannes Erdfelt <johannes@erdfelt.com>
Fixes: 444d13ff10 ("modules: add ro_after_init support")
Acked-by: Jessica Yu <jeyu@kernel.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 17:01:50 -04:00
Eiichi Tsukata
a4158345ec tracing/uprobe: Fix obsolete comment on trace_uprobe_create()
Commit 0597c49c69 ("tracing/uprobes: Use dyn_event framework for
uprobe events") cleaned up the usage of trace_uprobe_create(), and the
function has been no longer used for removing uprobe/uretprobe.

Link: http://lkml.kernel.org/r/20190614074026.8045-2-devel@etsukata.com

Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 17:00:36 -04:00
Eiichi Tsukata
f01098c74b tracing/uprobe: Fix NULL pointer dereference in trace_uprobe_create()
Just like the case of commit 8b05a3a750 ("tracing/kprobes: Fix NULL
pointer dereference in trace_kprobe_create()"), writing an incorrectly
formatted string to uprobe_events can trigger NULL pointer dereference.

Reporeducer:

  # echo r > /sys/kernel/debug/tracing/uprobe_events

dmesg:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 8000000079d12067 P4D 8000000079d12067 PUD 7b7ab067 PMD 0
  Oops: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 1903 Comm: bash Not tainted 5.2.0-rc3+ #15
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014
  RIP: 0010:strchr+0x0/0x30
  Code: c0 eb 0d 84 c9 74 18 48 83 c0 01 48 39 d0 74 0f 0f b6 0c 07 3a 0c 06 74 ea 19 c0 83 c8 01 c3 31 c0 c3 0f 1f 84 00 00 00 00 00 <0f> b6 07 89 f2 40 38 f0 75 0e eb 13 0f b6 47 01 48 83 c
  RSP: 0018:ffffb55fc0403d10 EFLAGS: 00010293

  RAX: ffff993ffb793400 RBX: 0000000000000000 RCX: ffffffffa4852625
  RDX: 0000000000000000 RSI: 000000000000002f RDI: 0000000000000000
  RBP: ffffb55fc0403dd0 R08: ffff993ffb793400 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
  R13: ffff993ff9cc1668 R14: 0000000000000001 R15: 0000000000000000
  FS:  00007f30c5147700(0000) GS:ffff993ffda00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000007b628000 CR4: 00000000000006f0
  Call Trace:
   trace_uprobe_create+0xe6/0xb10
   ? __kmalloc_track_caller+0xe6/0x1c0
   ? __kmalloc+0xf0/0x1d0
   ? trace_uprobe_create+0xb10/0xb10
   create_or_delete_trace_uprobe+0x35/0x90
   ? trace_uprobe_create+0xb10/0xb10
   trace_run_command+0x9c/0xb0
   trace_parse_run_command+0xf9/0x1eb
   ? probes_open+0x80/0x80
   __vfs_write+0x43/0x90
   vfs_write+0x14a/0x2a0
   ksys_write+0xa2/0x170
   do_syscall_64+0x7f/0x200
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Link: http://lkml.kernel.org/r/20190614074026.8045-1-devel@etsukata.com

Cc: stable@vger.kernel.org
Fixes: 0597c49c69 ("tracing/uprobes: Use dyn_event framework for uprobe events")
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 16:51:14 -04:00
YueHaibing
ff585c5b9a tracing: Make two symbols static
Fix sparse warnings:

kernel/trace/trace.c:6927:24: warning:
 symbol 'get_tracing_log_err' was not declared. Should it be static?
kernel/trace/trace.c:8196:15: warning:
 symbol 'trace_instance_dir' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20190614153210.24424-1-yuehaibing@huawei.com

Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 16:49:26 -04:00
Vasily Gorbik
cbdaeaf050 tracing: avoid build warning with HAVE_NOP_MCOUNT
Selecting HAVE_NOP_MCOUNT enables -mnop-mcount (if gcc supports it)
and sets CC_USING_NOP_MCOUNT. Reuse __is_defined (which is suitable for
testing CC_USING_* defines) to avoid conditional compilation and fix
the following gcc 9 warning on s390:

kernel/trace/ftrace.c:2514:1: warning: ‘ftrace_code_disable’ defined
but not used [-Wunused-function]

Link: http://lkml.kernel.org/r/patch.git-1a82d13f33ac.your-ad-here.call-01559732716-ext-6629@work.hours

Fixes: 2f4df0017b ("tracing: Add -mcount-nop option support")
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 16:34:57 -04:00
Eiichi Tsukata
becf33f694 tracing: Fix out-of-range read in trace_stack_print()
Puts range check before dereferencing the pointer.

Reproducer:

  # echo stacktrace > trace_options
  # echo 1 > events/enable
  # cat trace > /dev/null

KASAN report:

  ==================================================================
  BUG: KASAN: use-after-free in trace_stack_print+0x26b/0x2c0
  Read of size 8 at addr ffff888069d20000 by task cat/1953

  CPU: 0 PID: 1953 Comm: cat Not tainted 5.2.0-rc3+ #5
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014
  Call Trace:
   dump_stack+0x8a/0xce
   print_address_description+0x60/0x224
   ? trace_stack_print+0x26b/0x2c0
   ? trace_stack_print+0x26b/0x2c0
   __kasan_report.cold+0x1a/0x3e
   ? trace_stack_print+0x26b/0x2c0
   kasan_report+0xe/0x20
   trace_stack_print+0x26b/0x2c0
   print_trace_line+0x6ea/0x14d0
   ? tracing_buffers_read+0x700/0x700
   ? trace_find_next_entry_inc+0x158/0x1d0
   s_show+0xea/0x310
   seq_read+0xaa7/0x10e0
   ? seq_escape+0x230/0x230
   __vfs_read+0x7c/0x100
   vfs_read+0x16c/0x3a0
   ksys_read+0x121/0x240
   ? kernel_write+0x110/0x110
   ? perf_trace_sys_enter+0x8a0/0x8a0
   ? syscall_slow_exit_work+0xa9/0x410
   do_syscall_64+0xb7/0x390
   ? prepare_exit_to_usermode+0x165/0x200
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f867681f910
  Code: b6 fe ff ff 48 8d 3d 0f be 08 00 48 83 ec 08 e8 06 db 01 00 66 0f 1f 44 00 00 83 3d f9 2d 2c 00 00 75 10 b8 00 00 00 00 04
  RSP: 002b:00007ffdabf23488 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
  RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f867681f910
  RDX: 0000000000020000 RSI: 00007f8676cde000 RDI: 0000000000000003
  RBP: 00007f8676cde000 R08: ffffffffffffffff R09: 0000000000000000
  R10: 0000000000000871 R11: 0000000000000246 R12: 00007f8676cde000
  R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000000ec0

  Allocated by task 1214:
   save_stack+0x1b/0x80
   __kasan_kmalloc.constprop.0+0xc2/0xd0
   kmem_cache_alloc+0xaf/0x1a0
   getname_flags+0xd2/0x5b0
   do_sys_open+0x277/0x5a0
   do_syscall_64+0xb7/0x390
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

  Freed by task 1214:
   save_stack+0x1b/0x80
   __kasan_slab_free+0x12c/0x170
   kmem_cache_free+0x8a/0x1c0
   putname+0xe1/0x120
   do_sys_open+0x2c5/0x5a0
   do_syscall_64+0xb7/0x390
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

  The buggy address belongs to the object at ffff888069d20000
   which belongs to the cache names_cache of size 4096
  The buggy address is located 0 bytes inside of
   4096-byte region [ffff888069d20000, ffff888069d21000)
  The buggy address belongs to the page:
  page:ffffea0001a74800 refcount:1 mapcount:0 mapping:ffff88806ccd1380 index:0x0 compound_mapcount: 0
  flags: 0x100000000010200(slab|head)
  raw: 0100000000010200 dead000000000100 dead000000000200 ffff88806ccd1380
  raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffff888069d1ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
   ffff888069d1ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  >ffff888069d20000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                     ^
   ffff888069d20080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
   ffff888069d20100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ==================================================================

Link: http://lkml.kernel.org/r/20190610040016.5598-1-devel@etsukata.com

Fixes: 4285f2fcef ("tracing: Remove the ULONG_MAX stack trace hackery")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-06-14 16:28:42 -04:00
Greg Kroah-Hartman
3e6f176f30 blktrace: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-block@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-03 15:39:39 +02:00
Greg Kroah-Hartman
6a54cd872f trace: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-03 15:39:39 +02:00