Commit 0fcc4c8c authored by Jann Horn's avatar Jann Horn Committed by Tejun Heo

device_cgroup: fix RCU imbalance in error case

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: d591fb56 ("device_cgroup: simplify cgroup tree walk in propagate_exception()")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarJann Horn <jannh@google.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 9e98c678
...@@ -560,7 +560,7 @@ static int propagate_exception(struct dev_cgroup *devcg_root, ...@@ -560,7 +560,7 @@ static int propagate_exception(struct dev_cgroup *devcg_root,
devcg->behavior == DEVCG_DEFAULT_ALLOW) { devcg->behavior == DEVCG_DEFAULT_ALLOW) {
rc = dev_exception_add(devcg, ex); rc = dev_exception_add(devcg, ex);
if (rc) if (rc)
break; return rc;
} else { } else {
/* /*
* in the other possible cases: * in the other possible cases:
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment