ipc: fix double sem unlock in semctl error path

Fix another ipc locking buglet introduced by the scalability patches:
when semctl_down() was changed to delay the semaphore locking, one error
path for security_sem_semctl() went through the semaphore unlock logic
even though the semaphore had never been locked.

Introduced by commit 16df3674ef ("ipc,sem: do not hold ipc lock more
than necessary")

Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2013-05-04 10:25:11 -07:00
parent 4091fd942e
commit fbfd1d2862

View File

@ -1280,7 +1280,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid,
err = security_sem_semctl(sma, cmd);
if (err) {
rcu_read_unlock();
goto out_unlock;
goto out_up;
}
switch(cmd){