diff options
author | Jiri Slaby <jslaby@suse.cz> | 2012-10-25 13:37:34 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-25 14:37:52 -0700 |
commit | 8c9506d16925f1b1314d93af383ca3134eb534d8 (patch) | |
tree | e14dbc5816b375463b8d37eda0f79bcd0ea96a3b /samples/seccomp/bpf-helper.h | |
parent | ef5d437f71afdf4afdbab99213add99f4b1318fd (diff) |
cgroup: fix invalid rcu dereference
Commit ad676077a2ae ("device_cgroup: convert device_cgroup internally to
policy + exceptions") removed rcu locks which are needed in
task_devcgroup called in this chain:
devcgroup_inode_mknod OR __devcgroup_inode_permission ->
__devcgroup_inode_permission ->
task_devcgroup ->
task_subsys_state ->
task_subsys_state_check.
Change the code so that task_devcgroup is safely called with rcu read
lock held.
===============================
[ INFO: suspicious RCU usage. ]
3.6.0-rc5-next-20120913+ #42 Not tainted
-------------------------------
include/linux/cgroup.h:553 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
2 locks held by kdevtmpfs/23:
#0: (sb_writers){.+.+.+}, at: [<ffffffff8116873f>]
mnt_want_write+0x1f/0x50
#1: (&sb->s_type->i_mutex_key#3/1){+.+.+.}, at: [<ffffffff811558af>]
kern_path_create+0x7f/0x170
stack backtrace:
Pid: 23, comm: kdevtmpfs Not tainted 3.6.0-rc5-next-20120913+ #42
Call Trace:
lockdep_rcu_suspicious+0xfd/0x130
devcgroup_inode_mknod+0x19d/0x240
vfs_mknod+0x71/0xf0
handle_create.isra.2+0x72/0x200
devtmpfsd+0x114/0x140
? handle_create.isra.2+0x200/0x200
kthread+0xd6/0xe0
kernel_thread_helper+0x4/0x10
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Dave Jones <davej@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: James Morris <jmorris@namei.org>
Cc: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'samples/seccomp/bpf-helper.h')
0 files changed, 0 insertions, 0 deletions