[PATCH] add missing memory barriers to ipc/sem.c

Two smp_wmb() statements are missing in the sysv sem code: This could
cause stack corruptions.

The attached patch adds them.

Signed-Off-By: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Manfred Spraul 2005-12-23 23:57:41 +01:00 committed by Linus Torvalds
parent a7c2491a13
commit 6003a93e7b

View File

@ -381,6 +381,7 @@ static void update_queue (struct sem_array * sma)
/* hands-off: q will disappear immediately after
* writing q->status.
*/
smb_wmb();
q->status = error;
q = n;
} else {
@ -461,6 +462,7 @@ static void freeary (struct sem_array *sma, int id)
n = q->next;
q->status = IN_WAKEUP;
wake_up_process(q->sleeper); /* doesn't sleep */
smp_wmb();
q->status = -EIDRM; /* hands-off q */
q = n;
}