kernel_optimize_test/kernel/trace
Naveen N. Rao 760c6a6255 tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()
commit 823e670f7ed616d0ce993075c8afe0217885f79d upstream.

With the new osnoise tracer, we are seeing the below splat:
    Kernel attempted to read user page (c7d880000) - exploit attempt? (uid: 0)
    BUG: Unable to handle kernel data access on read at 0xc7d880000
    Faulting instruction address: 0xc0000000002ffa10
    Oops: Kernel access of bad area, sig: 11 [#1]
    LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
    ...
    NIP [c0000000002ffa10] __trace_array_vprintk.part.0+0x70/0x2f0
    LR [c0000000002ff9fc] __trace_array_vprintk.part.0+0x5c/0x2f0
    Call Trace:
    [c0000008bdd73b80] [c0000000001c49cc] put_prev_task_fair+0x3c/0x60 (unreliable)
    [c0000008bdd73be0] [c000000000301430] trace_array_printk_buf+0x70/0x90
    [c0000008bdd73c00] [c0000000003178b0] trace_sched_switch_callback+0x250/0x290
    [c0000008bdd73c90] [c000000000e70d60] __schedule+0x410/0x710
    [c0000008bdd73d40] [c000000000e710c0] schedule+0x60/0x130
    [c0000008bdd73d70] [c000000000030614] interrupt_exit_user_prepare_main+0x264/0x270
    [c0000008bdd73de0] [c000000000030a70] syscall_exit_prepare+0x150/0x180
    [c0000008bdd73e10] [c00000000000c174] system_call_vectored_common+0xf4/0x278

osnoise tracer on ppc64le is triggering osnoise_taint() for negative
duration in get_int_safe_duration() called from
trace_sched_switch_callback()->thread_exit().

The problem though is that the check for a valid trace_percpu_buffer is
incorrect in get_trace_buf(). The check is being done after calculating
the pointer for the current cpu, rather than on the main percpu pointer.
Fix the check to be against trace_percpu_buffer.

Link: https://lkml.kernel.org/r/a920e4272e0b0635cf20c444707cbce1b2c8973d.1640255304.git.naveen.n.rao@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Fixes: e2ace00117 ("tracing: Choose static tp_printk buffer by explicit nesting count")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-11 15:24:58 +01:00
..
blktrace.c blktrace: Fix uaf in blk_trace access after removing by sysfs 2021-09-30 10:11:05 +02:00
bpf_trace.c bpf: Add lockdown check for probe_write_user helper 2021-08-15 14:00:25 +02:00
bpf_trace.h bpf: Use dedicated bpf_trace_printk event instead of trace_printk() 2020-07-13 16:55:49 -07:00
fgraph.c fgraph: Initialize tracing_graph_pause at task creation 2021-02-10 09:29:16 +01:00
ftrace_internal.h x86/ftrace: Have ftrace trampolines turn read-only at the end of system boot up 2020-05-12 18:24:34 -04:00
ftrace.c tracing: Have all levels of checks prevent recursion 2021-10-27 09:56:56 +02:00
Kconfig tracing/kprobes: Do the notrace functions check without kprobes on ftrace 2021-01-19 18:27:19 +01:00
kprobe_event_gen_test.c tracing: Add kprobe event command generation test module 2020-01-30 09:46:28 -05:00
Makefile Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
power-traces.c
preemptirq_delay_test.c tracing: Wait for preempt irq delay thread to execute 2020-05-11 17:00:34 -04:00
ring_buffer_benchmark.c sched,tracing: Convert to sched_set_fifo() 2020-07-29 11:43:53 +02:00
ring_buffer.c ring-buffer: Protect ring_buffer_reset() from reentrancy 2021-11-18 14:03:49 +01:00
rpm-traces.c
synth_event_gen_test.c tracing: Add support for dynamic strings to synthetic events 2020-10-05 19:32:18 -04:00
trace_benchmark.c
trace_benchmark.h
trace_boot.c tracing/boot: Fix a hist trigger dependency for boot time tracing 2021-09-22 12:28:03 +02:00
trace_branch.c tracing: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
trace_clock.c tracing: Do no increment trace_clock_global() by one 2021-06-23 14:42:50 +02:00
trace_dynevent.c tracing: Delete repeated words in comments 2020-09-21 21:06:02 -04:00
trace_dynevent.h tracing: Remove check_arg() callbacks from dynevent args 2020-02-01 13:09:23 -05:00
trace_entries.h tracing: Make ftrace packed events have align of 1 2020-06-16 21:21:02 -04:00
trace_event_perf.c
trace_events_filter_test.h
trace_events_filter.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
trace_events_hist.c tracing/histograms: String compares should not care about signed values 2021-12-08 09:03:22 +01:00
trace_events_inject.c tracing: Initialize val to zero in parse_entry of inject code 2020-01-02 19:04:57 -05:00
trace_events_synth.c tracing: Make -ENOMEM the default error for parse_synth_field() 2020-11-02 15:58:32 -05:00
trace_events_trigger.c tracing: Fix event trigger to accept redundant spaces 2020-06-23 21:51:40 -04:00
trace_events.c tracing: Check pid filtering when creating events 2021-12-01 09:19:09 +01:00
trace_export.c treewide: Convert macro and uses of __section(foo) to __section("foo") 2020-10-25 14:51:49 -07:00
trace_functions_graph.c tracing: make tracing_init_dentry() returns an integer instead of a d_entry pointer 2020-09-18 22:17:14 -04:00
trace_functions.c tracing: Have all levels of checks prevent recursion 2021-10-27 09:56:56 +02:00
trace_hwlat.c tracing: Remove WARN_ON in start_thread() 2020-11-30 21:43:07 -05:00
trace_irqsoff.c tracing: Use pause-on-trace with the latency tracers 2021-02-10 09:29:16 +01:00
trace_kdb.c tracing: Rename trace_buffer to array_buffer 2020-01-13 13:19:38 -05:00
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_kprobe.c tracing/probes: Reject events which have the same name of existing one 2021-09-22 12:28:00 +02:00
trace_mmiotrace.c tracing: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
trace_nop.c
trace_output.c tracing: Make the space reserved for the pid wider 2020-09-18 12:42:11 -04:00
trace_output.h
trace_preemptirq.c lockdep: fix order in trace_hardirqs_off_caller() 2020-09-14 10:08:07 +02:00
trace_printk.c Updates for tracing and bootconfig: 2020-10-15 15:51:28 -07:00
trace_probe_tmpl.h
trace_probe.c tracing/probes: Reject events which have the same name of existing one 2021-09-22 12:28:00 +02:00
trace_probe.h tracing/probes: Reject events which have the same name of existing one 2021-09-22 12:28:00 +02:00
trace_sched_switch.c tracing: Fix sched switch start/stop refcount racy updates 2020-01-30 09:46:10 -05:00
trace_sched_wakeup.c tracing: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
trace_selftest_dynamic.c
trace_selftest.c tracing: Disable ftrace selftests when any tracer is running 2020-12-30 11:54:28 +01:00
trace_seq.c tracing: Remove unused TRACE_SEQ_BUF_USED 2020-01-21 18:39:54 -05:00
trace_stack.c tracing: make tracing_init_dentry() returns an integer instead of a d_entry pointer 2020-09-18 22:17:14 -04:00
trace_stat.c tracing: make tracing_init_dentry() returns an integer instead of a d_entry pointer 2020-09-18 22:17:14 -04:00
trace_stat.h
trace_synth.h tracing: Synthetic event field_pos is an index not a boolean 2021-07-28 14:35:45 +02:00
trace_syscalls.c Tracing updates: 2020-02-06 07:12:11 +00:00
trace_uprobe.c tracing/uprobe: Fix uprobe_perf_open probes iteration 2021-12-01 09:19:01 +01:00
trace.c tracing: Fix check for trace_percpu_buffer validity in get_trace_buf() 2022-01-11 15:24:58 +01:00
trace.h tracing: Fix pid filtering when triggers are attached 2021-12-01 09:19:01 +01:00
tracing_map.c tracing: Fix a kmemleak false positive in tracing_map 2021-12-17 10:14:40 +01:00
tracing_map.h