Pull cgroup changes from Tejun Heo:
"Out of the 8 commits, one fixes a long-standing locking issue around
tasklist walking and others are cleanups."
* 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: Walk task list under tasklist_lock in cgroup_enable_task_cg_list
cgroup: Remove wrong comment on cgroup_enable_task_cg_list()
cgroup: remove cgroup_subsys argument from callbacks
cgroup: remove extra calls to find_existing_css_set
cgroup: replace tasklist_lock with rcu_read_lock
cgroup: simplify double-check locking in cgroup_attach_proc
cgroup: move struct cgroup_pidlist out from the header file
cgroup: remove cgroup_attach_task_current_cg()
The following 4 functions:
move_addr_to_kernel
move_addr_to_user
verify_iovec
verify_compat_iovec
are always effectively called with a sockaddr_storage.
Make this explicit by changing their signature.
This removes a large number of casts from sockaddr_storage to sockaddr.
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/vmxnet3/vmxnet3_drv.c
Small vmxnet3 conflict with header size bug fix in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Some drivers use internal netdev stats member to store part of their
stats, yet advertize ndo_get_stats64() to implement some 64bit fields.
Allow them to use netdev_stats_to_stats64() helper to make the copy of
netdev stats before they compute their 64bit counters.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nlmsg_parse() might return an error, so test its return value before
potential random memory accesses.
Errors introduced in commit 115c9b8192 (rtnetlink: Fix problem with
buffer allocation)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add VF spoof check to IFLA policy. The original patch I submitted to
add the spoof checking feature to rtnl failed to add the proper policy
rule that identifies the data type and len. This patch corrects that
oversight. No bugs have been reported against this but it may cause
some problem for the netlink message parsing that uses the policy
table.
CC: stable@vger.kernel.org
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Conflicts:
drivers/net/ethernet/sfc/rx.c
Overlapping changes in drivers/net/ethernet/sfc/rx.c, one to change
the rx_buf->is_page boolean into a set of u16 flags, and another to
adjust how ->ip_summed is initialized.
Signed-off-by: David S. Miller <davem@davemloft.net>
Davem considers that the argument list of this interface is getting
out of control. This patch tries to address this issue following
his proposal:
struct netlink_dump_control c = { .dump = dump, .done = done, ... };
netlink_dump_start(..., &c);
Suggested by David S. Miller.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This flag requests that network devices pass all
received frames up the stack, even ones with errors
such as invalid FCS (frame check sum). This will
allow sniffers to see bad packets and perhaps
give the user some idea how to fix the problem.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This is useful for testing RX handling of frames with bad
CRCs.
Requires driver support to actually put the packet on the
wire properly.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
When set on hardware that supports the feature,
this causes the Ethernet FCS to be appended
to the end of the skb.
Useful for sniffing packets.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
So here's a boot tested patch on top of Jason's series that does
all the cleanups I talked about and turns jump labels into a
more intuitive to use facility. It should also address the
various misconceptions and confusions that surround jump labels.
Typical usage scenarios:
#include <linux/static_key.h>
struct static_key key = STATIC_KEY_INIT_TRUE;
if (static_key_false(&key))
do unlikely code
else
do likely code
Or:
if (static_key_true(&key))
do likely code
else
do unlikely code
The static key is modified via:
static_key_slow_inc(&key);
...
static_key_slow_dec(&key);
The 'slow' prefix makes it abundantly clear that this is an
expensive operation.
I've updated all in-kernel code to use this everywhere. Note
that I (intentionally) have not pushed through the rename
blindly through to the lowest levels: the actual jump-label
patching arch facility should be named like that, so we want to
decouple jump labels from the static-key facility a bit.
On non-jump-label enabled architectures static keys default to
likely()/unlikely() branches.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: a.p.zijlstra@chello.nl
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Implement a new netlink attribute type IFLA_EXT_MASK. The mask
is a 32 bit value that can be used to indicate to the kernel that
certain extended ifinfo values are requested by the user application.
At this time the only mask value defined is RTEXT_FILTER_VF to
indicate that the user wants the ifinfo dump to send information
about the VFs belonging to the interface.
This patch fixes a bug in which certain applications do not have
large enough buffers to accommodate the extra information returned
by the kernel with large numbers of SR-IOV virtual functions.
Those applications will not send the new netlink attribute with
the interface info dump request netlink messages so they will
not get unexpectedly large request buffers returned by the kernel.
Modifies the rtnl_calcit function to traverse the list of net
devices and compute the minimum buffer size that can hold the
info dumps of all matching devices based upon the filter passed
in via the new netlink attribute filter mask. If no filter
mask is sent then the buffer allocation defaults to NLMSG_GOODSIZE.
With this change it is possible to add yet to be defined netlink
attributes to the dump request which should make it fairly extensible
in the future.
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the fixed race condition happens:
1. While function neigh_periodic_work scans the neighbor hash table
pointed by field tbl->nht, it unlocks and locks tbl->lock between
buckets in order to call cond_resched.
2. Assume that function neigh_periodic_work calls cond_resched, that is,
the lock tbl->lock is available, and function neigh_hash_grow runs.
3. Once function neigh_hash_grow finishes, and RCU calls
neigh_hash_free_rcu, the original struct neigh_hash_table that function
neigh_periodic_work was using doesn't exist anymore.
4. Once back at neigh_periodic_work, whenever the old struct
neigh_hash_table is accessed, things can go badly.
Signed-off-by: Michel Machado <michel@digirati.com.br>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This one specifies where to start MSG_PEEK-ing queue data from. When
set to negative value means that MSG_PEEK works as ususally -- peeks
from the head of the queue always.
When some bytes are peeked from queue and the peeking offset is non
negative it is moved forward so that the next peek will return next
portion of data.
When non-peeking recvmsg occurs and the peeking offset is non negative
is is moved backward so that the next peek will still peek the proper
data (i.e. the one that would have been picked if there were no non
peeking recv in between).
The offset is set using per-proto opteration to let the protocol handle
the locking issues and to check whether the peeking offset feature is
supported by the protocol the socket belongs to.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This one is only considered for MSG_PEEK flag and the value pointed by
it specifies where to start peeking bytes from. If the offset happens to
point into the middle of the returned skb, the offset within this skb is
put back to this very argument.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes lines shorter and simplifies further patching.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c
Small minor conflict in bnx2x, wherein one commit changed how
statistics were stored in software, and another commit
fixed endianness bugs wrt. reading the values provided by
the chip in memory.
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 5a698af53f (bond: service netpoll arp queue on master device)
tested IFF_SLAVE flag against dev->priv_flags instead of dev->flags
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: WANG Cong <amwang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_gro_receive() doesnt update truesize properly when adding one skb to
frag_list.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
When the netprio_cgroup module is not loaded, net_prio_subsys_id
is -1, and so sock_update_prioidx() accesses cgroup_subsys array
with negative index subsys[-1].
Make the code resembles cls_cgroup code, which is bug free.
Origionally-authored-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
So we delay the allocation till the priority is set through cgroup,
and this makes skb_update_priority() faster when it's not set.
This also eliminates an off-by-one bug similar with the one fixed
in the previous patch.
Origionally-authored-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
# mount -t cgroup xxx /mnt
# mkdir /mnt/tmp
# cat /mnt/tmp/net_prio.ifpriomap
lo 0
eth0 0
virbr0 0
# echo 'lo 999' > /mnt/tmp/net_prio.ifpriomap
# cat /mnt/tmp/net_prio.ifpriomap
lo 999
eth0 0
virbr0 4101267344
We got weired output, because we exceeded the boundary of the array.
We may even crash the kernel..
Origionally-authored-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Shlomo Pongratz reported GRO L2 header check was suited for Ethernet
only, and failed on IB/ipoib traffic.
He provided a patch faking a zeroed header to let GRO aggregates frames.
Roland Dreier, Herbert Xu, and others suggested we change GRO L2 header
check to be more generic, ie not assuming L2 header is 14 bytes, but
taking into account hard_header_len.
__napi_gro_receive() has special handling for the common case (Ethernet)
to avoid a memcmp() call and use an inline optimized function instead.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Shlomo Pongratz <shlomop@mellanox.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Shlomo Pongratz reported GRO L2 header check was suited for Ethernet
only, and failed on IB/ipoib traffic.
He provided a patch faking a zeroed header to let GRO aggregates frames.
Roland Dreier, Herbert Xu, and others suggested we change GRO L2 header
check to be more generic, ie not assuming L2 header is 14 bytes, but
taking into account hard_header_len.
__napi_gro_receive() has special handling for the common case (Ethernet)
to avoid a memcmp() call and use an inline optimized function instead.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Shlomo Pongratz <shlomop@mellanox.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It was recently pointed out to me that the get_prioidx function sets a bit in
the prioidx map prior to checking to see if the index being set is out of
bounds. This patch corrects that, avoiding the possiblity of us writing beyond
the end of the array
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: Stanislaw Gruszka <sgruszka@redhat.com>
CC: Stanislaw Gruszka <sgruszka@redhat.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The argument is not used at all, and it's not necessary, because
a specific callback handler of course knows which subsys it
belongs to.
Now only ->pupulate() takes this argument, because the handlers of
this callback always call cgroup_add_file()/cgroup_add_files().
So we reduce a few lines of code, though the shrinking of object size
is minimal.
16 files changed, 113 insertions(+), 162 deletions(-)
text data bss dec hex filename
5486240 656987 7039960 13183187 c928d3 vmlinux.o.orig
5486170 656987 7039960 13183117 c9288d vmlinux.o
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Use the current logging style.
Coalesce formats where appropriate.
Update grammar where appropriate.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The parameters for ETHTOOL_FLASHDEV include a filename, which ought to
be null-terminated. Currently the only driver that implements
ethtool_ops::flash_device attempts to add a null terminator if
necessary, but does it wrongly. Do it in the ethtool core instead.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the types in the packet layout order.
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use a more current message logging style.
Add pr_fmt to prefix dmesg output with "netpoll: "
Add macros to print np->name.
Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add ability to return neighbour proxies list to caller if
it sent full ndmsg structure and has NTF_PROXY flag set.
Before this patch (and before iproute2 patches):
$ ip neigh add proxy 2001::1 dev eth0
$ ip -6 neigh show
$
After it and with applied iproute2 patches:
$ ip neigh add proxy 2001::1 dev eth0
$ ip -6 neigh show
2001::1 dev eth0 proxy
$
Compatibility with old versions of iproute2 is not broken,
kernel checks for incoming structure size and properly
works if old structure is came.
[v2]
* changed comments style.
* removed useless line with continue and curly bracket.
* changed incoming message size check from equal to more or
equal.
CC: davem@davemloft.net
CC: kuznet@ms2.inr.ac.ru
CC: netdev@vger.kernel.org
CC: xemul@parallels.com
Signed-off-by: Tony Zelenoff <antonz@parallels.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting link parameters on a netdevice changes the value
of if_nlmsg_size(), therefore it is necessary to recalculate
min_ifinfo_dump_size.
Signed-off-by: Stefan Gula <steweg@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a new net namespace is created, we should attach to it a "struct
net_generic" with enough slots (even empty), or we can hit the following
BUG_ON() :
[ 200.752016] kernel BUG at include/net/netns/generic.h:40!
...
[ 200.752016] [<ffffffff825c3cea>] ? get_cfcnfg+0x3a/0x180
[ 200.752016] [<ffffffff821cf0b0>] ? lockdep_rtnl_is_held+0x10/0x20
[ 200.752016] [<ffffffff825c41be>] caif_device_notify+0x2e/0x530
[ 200.752016] [<ffffffff810d61b7>] notifier_call_chain+0x67/0x110
[ 200.752016] [<ffffffff810d67c1>] raw_notifier_call_chain+0x11/0x20
[ 200.752016] [<ffffffff821bae82>] call_netdevice_notifiers+0x32/0x60
[ 200.752016] [<ffffffff821c2b26>] register_netdevice+0x196/0x300
[ 200.752016] [<ffffffff821c2ca9>] register_netdev+0x19/0x30
[ 200.752016] [<ffffffff81c1c67a>] loopback_net_init+0x4a/0xa0
[ 200.752016] [<ffffffff821b5e62>] ops_init+0x42/0x180
[ 200.752016] [<ffffffff821b600b>] setup_net+0x6b/0x100
[ 200.752016] [<ffffffff821b6466>] copy_net_ns+0x86/0x110
[ 200.752016] [<ffffffff810d5789>] create_new_namespaces+0xd9/0x190
net_alloc_generic() should take into account the maximum index into the
ptr array, as a subsystem might use net_generic() anytime.
This also reduces number of reallocations in net_assign_generic()
Reported-by: Sasha Levin <levinsasha928@gmail.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Sjur Brændeland <sjur.brandeland@stericsson.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The file net/core/flow_dissector.c seems to be missing
including linux/export.h.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allow ETHTOOL_GSSET_INFO ethtool ioctl() for unprivileged users.
ETHTOOL_GSTRINGS is already allowed, but is unusable without this one.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a case in __sk_mem_schedule(), where an allocation
is beyond the maximum, but yet we are allowed to proceed.
It happens under the following condition:
sk->sk_wmem_queued + size >= sk->sk_sndbuf
The network code won't revert the allocation in this case,
meaning that at some point later it'll try to do it. Since
this is never communicated to the underlying res_counter
code, there is an inbalance in res_counter uncharge operation.
I see two ways of fixing this:
1) storing the information about those allocations somewhere
in memcg, and then deducting from that first, before
we start draining the res_counter,
2) providing a slightly different allocation function for
the res_counter, that matches the original behavior of
the network code more closely.
I decided to go for #2 here, believing it to be more elegant,
since #1 would require us to do basically that, but in a more
obscure way.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
CC: Tejun Heo <tj@kernel.org>
CC: Li Zefan <lizf@cn.fujitsu.com>
CC: Laurent Chavey <chavey@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every call to num_args() immediately checks the return value for
less than zero, as it will return -EFAULT for a failed get_user()
call. So it makes no sense for the function to be declared as an
unsigned long.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (47 commits)
tg3: Fix single-vector MSI-X code
openvswitch: Fix multipart datapath dumps.
ipv6: fix per device IP snmp counters
inetpeer: initialize ->redirect_genid in inet_getpeer()
net: fix NULL-deref in WARN() in skb_gso_segment()
net: WARN if skb_checksum_help() is called on skb requiring segmentation
caif: Remove bad WARN_ON in caif_dev
caif: Fix typo in Vendor/Product-ID for CAIF modems
bnx2x: Disable AN KR work-around for BCM57810
bnx2x: Remove AutoGrEEEn for BCM84833
bnx2x: Remove 100Mb force speed for BCM84833
bnx2x: Fix PFC setting on BCM57840
bnx2x: Fix Super-Isolate mode for BCM84833
net: fix some sparse errors
net: kill duplicate included header
net: sh-eth: Fix build error by the value which is not defined
net: Use device model to get driver name in skb_gso_segment()
bridge: BH already disabled in br_fdb_cleanup()
net: move sock_update_memcg outside of CONFIG_INET
mwl8k: Fixing Sparse ENDIAN CHECK warning
...
skb_checksum_help() has never done anything useful with skbs that
require segmentation. Setting skb->ip_summed = CHECKSUM_NONE makes
them invalid and provokes a later WARNing in skb_gso_segment().
Passing such an skb to skb_checksum_help() indicates a bug, so we
should warn about it immediately. Move the warning from
skb_gso_segment() into a shared function, and add gso_type and
gso_size to it.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
make C=2 CF="-D__CHECK_ENDIAN__" M=net
And fix flowi4_init_output() prototype for sport
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ethtool operations generally require the caller to hold RTNL and are
not safe to call in atomic context. The device model provides this
information for most devices; we'll only lose it for some old ISA
drivers.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no store() method for inflight attribute in the
tx-<n>/byte_queue_limits sysfs directory.
So remove S_IWUSR bit.
Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://selinuxproject.org/~jmorris/linux-security:
capabilities: remove __cap_full_set definition
security: remove the security_netlink_recv hook as it is equivalent to capable()
ptrace: do not audit capability check when outputing /proc/pid/stat
capabilities: remove task_ns_* functions
capabitlies: ns_capable can use the cap helpers rather than lsm call
capabilities: style only - move capable below ns_capable
capabilites: introduce new has_ns_capabilities_noaudit
capabilities: call has_ns_capability from has_capability
capabilities: remove all _real_ interfaces
capabilities: introduce security_capable_noaudit
capabilities: reverse arguments to security_capable
capabilities: remove the task from capable LSM hook entirely
selinux: sparse fix: fix several warnings in the security server cod
selinux: sparse fix: fix warnings in netlink code
selinux: sparse fix: eliminate warnings for selinuxfs
selinux: sparse fix: declare selinux_disable() in security.h
selinux: sparse fix: move selinux_complete_init
selinux: sparse fix: make selinux_secmark_refcount static
SELinux: Fix RCU deref check warning in sel_netport_insert()
Manually fix up a semantic mis-merge wrt security_netlink_recv():
- the interface was removed in commit fd77846152 ("security: remove
the security_netlink_recv hook as it is equivalent to capable()")
- a new user of it appeared in commit a38f7907b9 ("crypto: Add
userspace configuration API")
causing no automatic merge conflict, but Eric Paris pointed out the
issue.
commit a9b3cd7f32 (rcu: convert uses of rcu_assign_pointer(x, NULL) to
RCU_INIT_POINTER) did a lot of incorrect changes, since it did a
complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x,
y).
We miss needed barriers, even on x86, when y is not NULL.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
> net/core/sock.c: In function 'sk_update_clone':
> net/core/sock.c:1278:3: error: implicit declaration of function 'sock_update_memcg'
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
dev_uc_sync() and dev_mc_sync() are acquiring netif_addr_lock for
destination device of synchronization. Since netif_addr_lock is
already held at the time for source device, this triggers lockdep
deadlock warning.
There's no way this deadlock can happen so use spin_lock_nested() to
silence the warning.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
so move it there. Fixes build errors when CONFIG_INET is not defined:
In file included from include/linux/tcp.h:211:0,
from include/linux/ipv6.h:221,
from include/net/ipv6.h:16,
from include/linux/sunrpc/clnt.h:26,
from include/linux/nfs_fs.h:50,
from init/do_mounts.c:20:
include/net/sock.h: In function 'sk_update_clone':
include/net/sock.h:1109:3: error: implicit declaration of function 'sock_update_memcg' [-Werror=implicit-function-declaration]
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In 882716604e "pktgen: fix multiple queue warning" we added special
logic to handle the case where ntxq is zero. It's not clear to me that
ntxq can actually be zero. But if it were then we would set
->queue_map_min and ->queue_map_max to USHRT_MAX when probably we want
to set them to zero?
Signed-off-by: David S. Miller <davem@davemloft.net>
Sockets can also be created through sock_clone. Because it copies
all data in the sock structure, it also copies the memcg-related pointer,
and all should be fine. However, since we now use reference counts in
socket creation, we are left with some sockets that have no reference
counts. It matters when we destroy them, since it leads to a mismatch.
Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: David S. Miller <davem@davemloft.net>
CC: Greg Thelen <gthelen@google.com>
CC: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: Laurent Chavey <chavey@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Once upon a time netlink was not sync and we had to get the effective
capabilities from the skb that was being received. Today we instead get
the capabilities from the current task. This has rendered the entire
purpose of the hook moot as it is now functionally equivalent to the
capable() call.
Signed-off-by: Eric Paris <eparis@redhat.com>
All implementations have been converted to implement set_rxnfc
instead.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Define special location values for RX NFC that request the driver to
select the actual rule location. This allows for implementation on
devices that use hash-based filter lookup, whereas currently the API is
more suited to devices with TCAM lookup or linear search.
In ethtool_set_rxnfc() and the compat wrapper ethtool_ioctl(), copy
the structure back to user-space after insertion so that the actual
location is returned.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a routine that dumps memory-related values of a socket.
It's made as an array to make it possible to add more stuff
here later without breaking compatibility.
Since v1: The SK_MEMINFO_ constants are in userspace
visible part of sock_diag.h, the rest is under __KERNEL__.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to perform a proper universal hash on a vector of integers,
we have to use different universal hashes on each vector element.
Which means we need 4 different hash randoms for ipv6.
Signed-off-by: David S. Miller <davem@davemloft.net>
Aim of this patch is to provide full range of rps_flow_cnt on 64bit arches.
Theorical limit on number of flows is 2^32
Fix some buggy RPS/RFS macros as well.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tom Herbert <therbert@google.com>
CC: Xi Wang <xi.wang@gmail.com>
CC: Laurent Chavey <chavey@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/bluetooth/l2cap_core.c
Just two overlapping changes, one added an initialization of
a local variable, and another change added a new local variable.
Signed-off-by: David S. Miller <davem@davemloft.net>
skb->truesize might be big even for a small packet.
Its even bigger after commit 87fb4b7b53 (net: more accurate skb
truesize) and big MTU.
We should allow queueing at least one packet per receiver, even with a
low RCVBUF setting.
Reported-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting a large rps_flow_cnt like (1 << 30) on 32-bit platform will
cause a kernel oops due to insufficient bounds checking.
if (count > 1<<30) {
/* Enforce a limit to prevent overflow */
return -EINVAL;
}
count = roundup_pow_of_two(count);
table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(count));
Note that the macro RPS_DEV_FLOW_TABLE_SIZE(count) is defined as:
... + (count * sizeof(struct rps_dev_flow))
where sizeof(struct rps_dev_flow) is 8. (1 << 30) * 8 will overflow
32 bits.
This patch replaces the magic number (1 << 30) with a symbolic bound.
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
flow_cach_flush() might sleep but can be called from
atomic context via the xfrm garbage collector. So add
a flow_cache_flush_deferred() function and use this if
the xfrm garbage colector is invoked from within the
packet path.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 5c3ddec73d.
S390 qeth driver actually still uses the setup ops.
Reported-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use IS_ENABLED(CONFIG_FOO)
instead of defined(CONFIG_FOO) || defined (CONFIG_FOO_MODULE)
Signed-off-by: Igor Maravić <igorm@etf.rs>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can't scan the proto_list to initialize sock cgroups, as it
holds a rwlock, and we also want to keep the code generic enough to
avoid calling the initialization functions of protocols directly,
Convert proto_list_lock into a mutex, so we can sleep and do the
necessary allocations. This lock is seldom taken, so there shouldn't
be any performance penalties associated with that
Signed-off-by: Glauber Costa <glommer@parallels.com>
CC: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
CC: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
All drivers that support modification of the RX flow hash indirection
table initialise it in the same way: RX rings are assigned to table
entries in rotation. Make that default policy explicit by having them
call a ethtool_rxfh_indir_default() function.
In the ethtool core, add support for a zero size value for
ETHTOOL_SRXFHINDIR, which resets the table to this default.
Partly-suggested-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Shreyas N Bhatewara <sbhatewara@vmware.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new ethtool operation (get_rxfh_indir_size) to get the
indirectional table size. Use this to validate the user buffer size
before calling get_rxfh_indir or set_rxfh_indir. Use get_rxnfc to get
the number of RX rings, and validate the contents of the new
indirection table before calling set_rxfh_indir. Remove this
validation from drivers.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sk address is used as a cookie between dump/get_exact calls.
It will be required for unix socket sdumping, so move it from
inet_diag to sock_diag.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I've made a mistake when fixing the sock_/inet_diag aliases :(
1. The sock_diag layer should request the family-based alias,
not just the IPPROTO_IP one;
2. The inet_diag layer should request for AF_INET+protocol alias,
not just the protocol one.
Thus fix this.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before adding a struct rtnl_link_ops into link_ops list, check it doesnt
clash with a prior one.
Based on a previous patch from Alexander Smirnov
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's simpler to just keep these things out until there is a real user
of them, so we can see what the needs actually are, rather than keep
these things around as useless overhead.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces memory pressure controls for the tcp
protocol. It uses the generic socket memory pressure code
introduced in earlier patches, and fills in the
necessary data in cg_proto struct.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtisu.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The goal of this work is to move the memory pressure tcp
controls to a cgroup, instead of just relying on global
conditions.
To avoid excessive overhead in the network fast paths,
the code that accounts allocated memory to a cgroup is
hidden inside a static_branch(). This branch is patched out
until the first non-root cgroup is created. So when nobody
is using cgroups, even if it is mounted, no significant performance
penalty should be seen.
This patch handles the generic part of the code, and has nothing
tcp-specific.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujtsu.com>
CC: Kirill A. Shutemov <kirill@shutemov.name>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch replaces all uses of struct sock fields' memory_pressure,
memory_allocated, sockets_allocated, and sysctl_mem to acessor
macros. Those macros can either receive a socket argument, or a mem_cgroup
argument, depending on the context they live in.
Since we're only doing a macro wrapping here, no performance impact at all is
expected in the case where we don't have cgroups disabled.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com>
CC: David S. Miller <davem@davemloft.net>
CC: Eric W. Biederman <ebiederm@xmission.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 865d9f9f74.
This commit breaks the build with CONFIG_NETPRIO_CGROUP=y so
revert it. It does build as a module though. The SUBSYS macro
in the cgroup core code automatically defines a subsys structure
as extern. Long term we should fix the macro. And I need to
fully build test things.
Tested with CONFIG_NETPRIO_CGROUP={y|m|n} with and without
CONFIG_CGROUPS defined.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Reported-By: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These tests are off by one because sock_diag_handlers[] only has AF_MAX
elements.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net_prio_subsys can be made static this removes the sparse
warning it was throwing.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On a CONFIG_NET=y build
net/core/secure_seq.c:22: warning: 'seq_scale' defined but not
used
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moves the sock_ code from inet_diag.c to generic sock_diag.c
file and provides necessary request_module-s calls and a pointer on
inet_diag_compat dumping routine.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit c5ed63d66f24(tcp: fix three tcp sysctls tuning),
sysctl_max_syn_backlog is determined by tcp_hashinfo->ehash_mask,
and the minimal value is 128, and it will increase in proportion to the
memory of machine.
The original description for tcp_max_syn_backlog and sysctl_max_syn_backlog
are out of date.
Changelog:
V2: update description for sysctl_max_syn_backlog
Signed-off-by: Weiping Pan <panweiping3@gmail.com>
Reviewed-by: Shan Wei <shanwei88@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netdev_queue_release() should be called even if CONFIG_XPS=n
to properly release device reference.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To reflect the fact that a refrence is not obtained to the
resulting neighbour entry.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Roland Dreier <roland@purestorage.com>
We discovered that TCP stack could retransmit misaligned skbs if a
malicious peer acknowledged sub MSS frame. This currently can happen
only if output interface is non SG enabled : If SG is enabled, tcp
builds headless skbs (all payload is included in fragments), so the tcp
trimming process only removes parts of skb fragments, header stay
aligned.
Some arches cant handle misalignments, so force a head reallocation and
shrink headroom to MAX_TCP_HEADER.
Dont care about misaligments on x86 and PPC (or other arches setting
NET_IP_ALIGN to 0)
This patch introduces __pskb_copy() which can specify the headroom of
new head, and pskb_copy() becomes a wrapper on top of __pskb_copy()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit b00055aacd ([NET] core: add RFC2863 operstate) changed
net_device flags from unsigned short to unsigned int.
Some core functions still assume its an unsigned short.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Within nested statements, the break statement terminates only the
do, for, switch, or while statement that immediately encloses it,
So replace the break with goto.
Signed-off-by: RongQing.Li <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netdev->neigh_priv_len records the private area length.
This will trigger for neigh_table objects which set tbl->entry_size
to zero, and the first instances of this will be forthcoming.
Signed-off-by: David S. Miller <davem@davemloft.net>
We are going to alloc for device specific private areas for
neighbour entries, and in order to do that we have to move
away from the fixed allocation size enforced by using
neigh_table->kmem_cachep
As a nice side effect we can now use kfree_rcu().
Signed-off-by: David S. Miller <davem@davemloft.net>
Change function rcu_dereference to rcu_dereference_bh to avoid warning
[ INFO: suspicious RCU usage. ]
-------------------------------
net/core/dev.c:2459 suspicious rcu_dereference_check() usage!
because we are locking with
rcu_read_lock_bh();
in function dev_queue_xmit(struct sk_buff *skb)
Signed-off-by: Igor Maravic <igorm@etf.rs>
Signed-off-by: David S. Miller <davem@davemloft.net>
Le lundi 28 novembre 2011 à 19:06 -0500, David Miller a écrit :
> From: Dimitris Michailidis <dm@chelsio.com>
> Date: Mon, 28 Nov 2011 08:25:39 -0800
>
> >> +bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys
> >> *flow)
> >> +{
> >> + int poff, nhoff = skb_network_offset(skb);
> >> + u8 ip_proto;
> >> + u16 proto = skb->protocol;
> >
> > __be16 instead of u16 for proto?
>
> I'll take care of this when I apply these patches.
( CC trimmed )
Thanks David !
Here is a small patch to use one 64bit load/store on x86_64 instead of
two 32bit load/stores.
[PATCH net-next] flow_dissector: use a 64bit load/store
gcc compiler is smart enough to use a single load/store if we
memcpy(dptr, sptr, 8) on x86_64, regardless of
CONFIG_CC_OPTIMIZE_FOR_SIZE
In IP header, daddr immediately follows saddr, this wont change in the
future. We only need to make sure our flow_keys (src,dst) fields wont
break the rule.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Networking stack support for byte queue limits, uses dynamic queue
limits library. Byte queue limits are maintained per transmit queue,
and a dql structure has been added to netdev_queue structure for this
purpose.
Configuration of bql is in the tx-<n> sysfs directory for the queue
under the byte_queue_limits directory. Configuration includes:
limit_min, bql minimum limit
limit_max, bql maximum limit
hold_time, bql slack hold time
Also under the directory are:
limit, current byte limit
inflight, current number of bytes on the queue
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moves the xps specific parts in netdev_queue_release into
its own function which netdev_queue_release can call. This allows
netdev_queue_release to be more generic (for adding new attributes
to tx queues).
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create separate queue state flags so that either the stack or drivers
can turn on XOFF. Added a set of functions used in the stack to determine
if a queue is really stopped (either by stack or driver)
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can test/set multiple bits from sk_flags at once, to shorten a bit
socket setup/dismantle phase.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Igor Maravic reported an error caused by jump_label_dec() being called
from IRQ context :
BUG: sleeping function called from invalid context at kernel/mutex.c:271
in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper
1 lock held by swapper/0:
#0: (&n->timer){+.-...}, at: [<ffffffff8107ce90>] call_timer_fn+0x0/0x340
Pid: 0, comm: swapper Not tainted 3.2.0-rc2-net-next-mpls+ #1
Call Trace:
<IRQ> [<ffffffff8104f417>] __might_sleep+0x137/0x1f0
[<ffffffff816b9a2f>] mutex_lock_nested+0x2f/0x370
[<ffffffff810a89fd>] ? trace_hardirqs_off+0xd/0x10
[<ffffffff8109a37f>] ? local_clock+0x6f/0x80
[<ffffffff810a90a5>] ? lock_release_holdtime.part.22+0x15/0x1a0
[<ffffffff81557929>] ? sock_def_write_space+0x59/0x160
[<ffffffff815e936e>] ? arp_error_report+0x3e/0x90
[<ffffffff810969cd>] atomic_dec_and_mutex_lock+0x5d/0x80
[<ffffffff8112fc1d>] jump_label_dec+0x1d/0x50
[<ffffffff81566525>] net_disable_timestamp+0x15/0x20
[<ffffffff81557a75>] sock_disable_timestamp+0x45/0x50
[<ffffffff81557b00>] __sk_free+0x80/0x200
[<ffffffff815578d0>] ? sk_send_sigurg+0x70/0x70
[<ffffffff815e936e>] ? arp_error_report+0x3e/0x90
[<ffffffff81557cba>] sock_wfree+0x3a/0x70
[<ffffffff8155c2b0>] skb_release_head_state+0x70/0x120
[<ffffffff8155c0b6>] __kfree_skb+0x16/0x30
[<ffffffff8155c119>] kfree_skb+0x49/0x170
[<ffffffff815e936e>] arp_error_report+0x3e/0x90
[<ffffffff81575bd9>] neigh_invalidate+0x89/0xc0
[<ffffffff81578dbe>] neigh_timer_handler+0x9e/0x2a0
[<ffffffff81578d20>] ? neigh_update+0x640/0x640
[<ffffffff81073558>] __do_softirq+0xc8/0x3a0
Since jump_label_{inc|dec} must be called from process context only,
we must defer jump_label_dec() if net_disable_timestamp() is called
from interrupt context.
Reported-by: Igor Maravic <igorm@etf.rs>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No functional changes.
This uses the code we factorized in skb_flow_dissect()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We use at least two flow dissectors in network stack, with known
limitations and code duplication.
Introduce skb_flow_dissect() to factorize this, highly inspired from
existing dissector from __skb_get_rxhash()
Note : We extensively use skb_header_pointer(), this permits us to not
touch skb at all.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I just hit this during my testing. Isn't there another bug lurking?
BUG kmalloc-8: Redzone overwritten
INFO: 0xc0000000de9dec48-0xc0000000de9dec4b. First byte 0x0 instead of 0xcc
INFO: Allocated in .__seq_open_private+0x30/0xa0 age=0 cpu=5 pid=3896
.__kmalloc+0x1e0/0x2d0
.__seq_open_private+0x30/0xa0
.seq_open_net+0x60/0xe0
.dev_mc_seq_open+0x4c/0x70
.proc_reg_open+0xd8/0x260
.__dentry_open.clone.11+0x2b8/0x400
.do_last+0xf4/0x950
.path_openat+0xf8/0x480
.do_filp_open+0x48/0xc0
.do_sys_open+0x140/0x250
syscall_exit+0x0/0x40
dev_mc_seq_ops uses dev_seq_start/next/stop but only allocates
sizeof(struct seq_net_private) of private data, whereas it expects
sizeof(struct dev_iter_state):
struct dev_iter_state {
struct seq_net_private p;
unsigned int pos; /* bucket << BUCKET_SPACE + offset */
};
Create dev_seq_open_ops and use it so we don't have to expose
struct dev_iter_state.
[ Problem added by commit f04565ddf5 (dev: use name hash for
dev_seq_ops) -Eric ]
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Skip entries from foreign network namespaces.
Signed-off-by: Jorge Boncompte [DTI2] <jorge@dti2.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_assign_pointer(ptr, NULL) can be safely replaced by
RCU_INIT_POINTER(ptr, NULL)
(old rcu_assign_pointer() macro was testing the NULL value and could
omit the smp_wmb(), but this had to be removed because of compiler
warnings)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
C assignment can handle struct in6_addr copying.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
when skb_shift, we want to shift paged data from skb to tgt frag area.
Original comments revert the shift order
Signed-off-by: Feng King <kinwin2008@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds in the infrastructure code to create the network priority
cgroup. The cgroup, in addition to the standard processes file creates two
control files:
1) prioidx - This is a read-only file that exports the index of this cgroup.
This is a value that is both arbitrary and unique to a cgroup in this subsystem,
and is used to index the per-device priority map
2) priomap - This is a writeable file. On read it reports a table of 2-tuples
<name:priority> where name is the name of a network interface and priority is
indicates the priority assigned to frames egresessing on the named interface and
originating from a pid in this cgroup
This cgroup allows for skb priority to be set prior to a root qdisc getting
selected. This is benenficial for DCB enabled systems, in that it allows for any
application to use dcb configured priorities so without application modification
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
CC: Robert Love <robert.w.love@intel.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Remove all uses of LL_ALLOCATED_SPACE
The macro LL_ALLOCATED_SPACE was ill-conceived. It applies the
alignment to the sum of needed_headroom and needed_tailroom. As
the amount that is then reserved for head room is needed_headroom
with alignment, this means that the tail room left may be too small.
This patch replaces all uses of LL_ALLOCATED_SPACE with the macro
LL_RESERVED_SPACE and direct reference to needed_tailroom.
This also fixes the problem with needed_headroom changing between
allocating the skb and reserving the head room.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Most machines dont use RPS/RFS, and pay a fair amount of instructions in
netif_receive_skb() / netif_rx() / get_rps_cpu() just to discover
RPS/RFS is not setup.
Add a jump_label named rps_needed.
If no device rps_map or global rps_sock_flow_table is setup,
netif_receive_skb() / netif_rx() do a single instruction instead of many
ones, including conditional jumps.
jmp +0 (if CONFIG_JUMP_LABEL=y)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds the /sys/class/net/DEV/queues/Q/tx_timeout attribute
containing the total number of timeout events on the given queue. It
is always available with CONFIG_SYSFS, independently of
CONFIG_RPS/XPS.
Credits to Stephen Hemminger for a preliminary version of this patch.
Tested:
without CONFIG_SYSFS (compilation only)
with sysfs and without CONFIG_RPS & CONFIG_XPS
with sysfs and without CONFIG_RPS
with sysfs and without CONFIG_XPS
with defaults
Signed-off-by: David Decotigny <david.decotigny@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit fixes following warning:
net/core/net-sysfs.c:921:6: warning: symbol 'numa_node' shadows an earlier one
include/linux/topology.h:222:1: originally declared here
Signed-off-by: David Decotigny <david.decotigny@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add missing spaces around multiplication operator.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only distinct use is checking if NETIF_F_NOCACHE_COPY should be
enabled by default. The check heuristics is altered a bit here,
so it hits other people than before. The default shouldn't be
trusted for performance-critical cases anyway.
For all other uses NETIF_F_NO_CSUM is equivalent to NETIF_F_HW_CSUM.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
v2: changed loop in ethtool_set_features() per Ben's suggestion
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
v2: add couple missing conversions in drivers
split unexporting netdev_fix_features()
implemented %pNF
convert sock::sk_route_(no?)caps
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is the only place left where dev->features are directly
exposed to userspace.
I know checkpatch.pl complains about __ethtool_{get,set}_flags(), but
the code is easier to read this way.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As all drivers are converted, we may now remove discrete offload setting
callback handling.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netstamp_needed seems a good candidate to jump_label conversion.
This avoids 3 conditional branches per incoming packet in fast path.
No measurable difference, given that these conditional branches are
predicted on modern cpus. Only a small icache reduction, thanks to the
unlikely() stuff.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One of the thing we discussed during netdev 2011 conference was the idea
to change some network drivers to allocate/populate their skb at RX
completion time, right before feeding the skb to network stack.
In old days, we allocated skbs when populating the RX ring.
This means bringing into cpu cache sk_buff and skb_shared_info cache
lines (since we clear/initialize them), then 'queue' skb->data to NIC.
By the time NIC fills a frame in skb->data buffer and host can process
it, cpu probably threw away the cache lines from its caches, because lot
of things happened between the allocation and final use.
So the deal would be to allocate only the data buffer for the NIC to
populate its RX ring buffer. And use build_skb() at RX completion to
attach a data buffer (now filled with an ethernet frame) to a new skb,
initialize the skb_shared_info portion, and give the hot skb to network
stack.
build_skb() is the function to allocate an skb, caller providing the
data buffer that should be attached to it. Drivers are expected to call
skb_reserve() right after build_skb() to adjust skb->data to the
Ethernet frame (usually skipping NET_SKB_PAD and NET_IP_ALIGN, but some
drivers might add a hardware provided alignment)
Data provided to build_skb() MUST have been allocated by a prior
kmalloc() call, with enough room to add SKB_DATA_ALIGN(sizeof(struct
skb_shared_info)) bytes at the end of the data without corrupting
incoming frame.
data = kmalloc(NET_SKB_PAD + NET_IP_ALIGN + 1536 +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
GFP_ATOMIC);
...
skb = build_skb(data);
if (!skb) {
recycle_data(data);
} else {
skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
...
}
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Eilon Greenstein <eilong@broadcom.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: Tom Herbert <therbert@google.com>
CC: Jamal Hadi Salim <hadi@mojatatu.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Thomas Graf <tgraf@infradead.org>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Le mercredi 09 novembre 2011 à 16:21 -0500, David Miller a écrit :
> From: David Miller <davem@davemloft.net>
> Date: Wed, 09 Nov 2011 16:16:44 -0500 (EST)
>
> > From: Eric Dumazet <eric.dumazet@gmail.com>
> > Date: Wed, 09 Nov 2011 12:14:09 +0100
> >
> >> unres_qlen is the number of frames we are able to queue per unresolved
> >> neighbour. Its default value (3) was never changed and is responsible
> >> for strange drops, especially if IP fragments are used, or multiple
> >> sessions start in parallel. Even a single tcp flow can hit this limit.
> > ...
> >
> > Ok, I've applied this, let's see what happens :-)
>
> Early answer, build fails.
>
> Please test build this patch with DECNET enabled and resubmit. The
> decnet neigh layer still refers to the removed ->queue_len member.
>
> Thanks.
Ouch, this was fixed on one machine yesterday, but not the other one I
used this morning, sorry.
[PATCH V5 net-next] neigh: new unresolved queue limits
unres_qlen is the number of frames we are able to queue per unresolved
neighbour. Its default value (3) was never changed and is responsible
for strange drops, especially if IP fragments are used, or multiple
sessions start in parallel. Even a single tcp flow can hit this limit.
$ arp -d 192.168.20.108 ; ping -c 2 -s 8000 192.168.20.108
PING 192.168.20.108 (192.168.20.108) 8000(8028) bytes of data.
8008 bytes from 192.168.20.108: icmp_seq=2 ttl=64 time=0.322 ms
Signed-off-by: David S. Miller <davem@davemloft.net>
The 802.1X EAPOL handshake hostapd does requires
knowing whether the frame was ack'ed by the peer.
Currently, we fudge this pretty badly by not even
transmitting the frame as a normal data frame but
injecting it with radiotap and getting the status
out of radiotap monitor as well. This is rather
complex, confuses users (mon.wlan0 presence) and
doesn't work with all hardware.
To get rid of that hack, introduce a real wifi TX
status option for data frame transmissions.
This works similar to the existing TX timestamping
in that it reflects the SKB back to the socket's
error queue with a SCM_WIFI_STATUS cmsg that has
an int indicating ACK status (0/1).
Since it is possible that at some point we will
want to have TX timestamping and wifi status in a
single errqueue SKB (there's little point in not
doing that), redefine SO_EE_ORIGIN_TIMESTAMPING
to SO_EE_ORIGIN_TXSTATUS which can collect more
than just the timestamp; keep the old constant
as an alias of course. Currently the internal APIs
don't make that possible, but it wouldn't be hard
to split them up in a way that makes it possible.
Thanks to Neil Horman for helping me figure out
the functions that add the control messages.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Make clear that sk_clone() and inet_csk_clone() return a locked socket.
Add _lock() prefix and kerneldoc.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
Whatever situations make this state legitimate when SMP
also would be legitimate when !SMP and f.e. preemption is
enabled.
This is dubious enough that we should just delete it entirely. If we
want to add debugging for neigh timer races, better more thorough
mechanisms are needed.
Signed-off-by: David S. Miller <davem@davemloft.net>
These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
With calls to modular infrastructure, these files really
needs the full module.h header. Call it out so some of the
cleanups of implicit and unrequired includes elsewhere can be
cleaned up.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
commit 2425717b27 (net: allow vlan traffic to be received under bond)
broke ARP processing on vlan on top of bonding.
+-------+
eth0 --| bond0 |---bond0.103
eth1 --| |
+-------+
52870.115435: skb_gro_reset_offset <-napi_gro_receive
52870.115435: dev_gro_receive <-napi_gro_receive
52870.115435: napi_skb_finish <-napi_gro_receive
52870.115435: netif_receive_skb <-napi_skb_finish
52870.115435: get_rps_cpu <-netif_receive_skb
52870.115435: __netif_receive_skb <-netif_receive_skb
52870.115436: vlan_do_receive <-__netif_receive_skb
52870.115436: bond_handle_frame <-__netif_receive_skb
52870.115436: vlan_do_receive <-__netif_receive_skb
52870.115436: arp_rcv <-__netif_receive_skb
52870.115436: kfree_skb <-arp_rcv
Packet is dropped in arp_rcv() because its pkt_type was set to
PACKET_OTHERHOST in the first vlan_do_receive() call, since no eth0.103
exists.
We really need to change pkt_type only if no more rx_handler is about to
be called for the packet.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1745 commits)
dp83640: free packet queues on remove
dp83640: use proper function to free transmit time stamping packets
ipv6: Do not use routes from locally generated RAs
|PATCH net-next] tg3: add tx_dropped counter
be2net: don't create multiple RX/TX rings in multi channel mode
be2net: don't create multiple TXQs in BE2
be2net: refactor VF setup/teardown code into be_vf_setup/clear()
be2net: add vlan/rx-mode/flow-control config to be_setup()
net_sched: cls_flow: use skb_header_pointer()
ipv4: avoid useless call of the function check_peer_pmtu
TCP: remove TCP_DEBUG
net: Fix driver name for mdio-gpio.c
ipv4: tcp: fix TOS value in ACK messages sent from TIME_WAIT
rtnetlink: Add missing manual netlink notification in dev_change_net_namespaces
ipv4: fix ipsec forward performance regression
jme: fix irq storm after suspend/resume
route: fix ICMP redirect validation
net: hold sock reference while processing tx timestamps
tcp: md5: add more const attributes
Add ethtool -g support to virtio_net
...
Fix up conflicts in:
- drivers/net/Kconfig:
The split-up generated a trivial conflict with removal of a
stale reference to Documentation/networking/net-modules.txt.
Remove it from the new location instead.
- fs/sysfs/dir.c:
Fairly nasty conflicts with the sysfs rb-tree usage, conflicting
with Eric Biederman's changes for tagged directories.
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (38 commits)
mm: memory hotplug: Check if pages are correctly reserved on a per-section basis
Revert "memory hotplug: Correct page reservation checking"
Update email address for stable patch submission
dynamic_debug: fix undefined reference to `__netdev_printk'
dynamic_debug: use a single printk() to emit messages
dynamic_debug: remove num_enabled accounting
dynamic_debug: consolidate repetitive struct _ddebug descriptor definitions
uio: Support physical addresses >32 bits on 32-bit systems
sysfs: add unsigned long cast to prevent compile warning
drivers: base: print rejected matches with DEBUG_DRIVER
memory hotplug: Correct page reservation checking
memory hotplug: Refuse to add unaligned memory regions
remove the messy code file Documentation/zh_CN/SubmitChecklist
ARM: mxc: convert device creation to use platform_device_register_full
new helper to create platform devices with dma mask
docs/driver-model: Update device class docs
docs/driver-model: Document device.groups
kobj_uevent: Ignore if some listeners cannot handle message
dynamic_debug: make netif_dbg() call __netdev_printk()
dynamic_debug: make netdev_dbg() call __netdev_printk()
...
Renato Westphal noticed that since commit a2835763e1
"rtnetlink: handle rtnl_link netlink notifications manually" was merged
we no longer send a netlink message when a networking device is moved
from one network namespace to another.
Fix this by adding the missing manual notification in dev_change_net_namespaces.
Since all network devices that are processed by dev_change_net_namspaces are
in the initialized state the complicated tests that guard the manual
rtmsg_ifinfo calls in rollback_registered and register_netdevice are
unnecessary and we can just perform a plain notification.
Cc: stable@kernel.org
Tested-by: Renato Westphal <renatowestphal@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The pair of functions,
* skb_clone_tx_timestamp()
* skb_complete_tx_timestamp()
were designed to allow timestamping in PHY devices. The first
function, called during the MAC driver's hard_xmit method, identifies
PTP protocol packets, clones them, and gives them to the PHY device
driver. The PHY driver may hold onto the packet and deliver it at a
later time using the second function, which adds the packet to the
socket's error queue.
As pointed out by Johannes, nothing prevents the socket from
disappearing while the cloned packet is sitting in the PHY driver
awaiting a timestamp. This patch fixes the issue by taking a reference
on the socket for each such packet. In addition, the comments
regarding the usage of these function are expanded to highlight the
rule that PHY drivers must use skb_complete_tx_timestamp() to release
the packet, in order to release the socket reference, too.
These functions first appeared in v2.6.36.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Cc: <stable@vger.kernel.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adding const qualifiers to pointers can ease code review, and spot some
bugs. It might allow compiler to optimize code further.
For example, is it legal to temporary write a null cksum into tcphdr
in tcp_md5_hash_header() ? I am afraid a sniffer could catch the
temporary null value...
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using the dev->next chain and trying to resync at each call to
dev_seq_start, use the name hash, keeping the bucket and the offset in
seq->private field.
Tests revealed the following results for ifconfig > /dev/null
* 1000 interfaces:
* 0.114s without patch
* 0.089s with patch
* 3000 interfaces:
* 0.489s without patch
* 0.110s with patch
* 5000 interfaces:
* 1.363s without patch
* 0.250s with patch
* 128000 interfaces (other setup):
* ~100s without patch
* ~30s with patch
Signed-off-by: Mihai Maruseac <mmaruseac@ixiacom.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I've split this bit out of the skb frag destructor patch since it helps enforce
the use of the fragment API.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Turull reported inaccuracies in pktgen when using low packet
rates, because we call ndelay(val) with values bigger than 20000.
Instead of calling ndelay() for delays < 100us, we can instead loop
calling ktime_now() only.
Reported-by: Daniel Turull <daniel.turull@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I audited all of the callers in the tree and only one of them (pktgen) expects
it to do so. Taking this reference is pretty obviously confusing and error
prone.
In particular I looked at the following commits which switched callers of
(__)skb_frag_set_page to the skb paged fragment api:
6a930b9f16 cxgb3: convert to SKB paged frag API.
5dc3e196ea myri10ge: convert to SKB paged frag API.
0e0634d20d vmxnet3: convert to SKB paged frag API.
86ee8130a4 virtionet: convert to SKB paged frag API.
4a22c4c919 sfc: convert to SKB paged frag API.
18324d690d cassini: convert to SKB paged frag API.
b061b39e3a benet: convert to SKB paged frag API.
b7b6a688d2 bnx2: convert to SKB paged frag API.
804cf14ea5 net: xfrm: convert to SKB frag APIs
ea2ab69379 net: convert core to skb paged frag APIs
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is just a cleanup.
My testing version of Smatch warns about this:
net/core/filter.c +380 check_load_and_stores(6)
warn: check 'flen' for negative values
flen comes from the user. We try to clamp the values here between 1
and BPF_MAXINSNS but the clamp doesn't work because it could be
negative. This is a bug, but it's not exploitable.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
