| author | Jann Horn <jannh@google.com> | 2019-03-19 01:36:59 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-27 07:34:46 (GMT) |
| commit | b2b28629c69321ed59fdeaa6514691e04318cf13 (patch) | |
| tree | 09250785b86477e3e0b8eaa39d43ec85f937fa8f | |
| parent | 33f2a3e176bd508e369e34d171909acada064704 (diff) | |
| download | common-b2b28629c69321ed59fdeaa6514691e04318cf13.zip common-b2b28629c69321ed59fdeaa6514691e04318cf13.tar.gz common-b2b28629c69321ed59fdeaa6514691e04318cf13.tar.bz2 | |
device_cgroup: fix RCU imbalance in error case
commit 0fcc4c8c044e117ac126ab6df4138ea9a67fa2a9 upstream.
When dev_exception_add() returns an error (due to a failed memory
allocation), make sure that we move the RCU preemption count back to where
it was before we were called. We dropped the RCU read lock inside the loop
body, so we can't just "break".
sparse complains about this, too:
$ make -s C=2 security/device_cgroup.o
./include/linux/rcupdate.h:647:9: warning: context imbalance in
'propagate_exception' - unexpected unlock
Fixes: d591fb56618f ("device_cgroup: simplify cgroup tree walk in propagate_exception()")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | security/device_cgroup.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/security/device_cgroup.c b/security/device_cgroup.c index 03c1652..db3bdc9 100644 --- a/security/device_cgroup.c +++ b/security/device_cgroup.c @@ -568,7 +568,7 @@ static int propagate_exception(struct dev_cgroup *devcg_root, devcg->behavior == DEVCG_DEFAULT_ALLOW) { rc = dev_exception_add(devcg, ex); if (rc) - break; + return rc; } else { /* * in the other possible cases: |