ipc/sem.c: prevent queue.status tearing in semop

In order for load/store tearing prevention to work, _all_ accesses to
the variable in question need to be done around READ and WRITE_ONCE()
macros.  Ensure everyone does so for q->status variable for
semtimedop().

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Davidlohr Bueso <[email protected]>
Cc: Manfred Spraul <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Davidlohr Bueso 2018-07-26 16:37:19 -07:00 • committed by Linus Torvalds
commit f075faa300

View file

@ -2118,7 +2118,7 @@ static long do_semtimedop(int semid, struct sembuf __user *tsops,
}
do {
queue.status = -EINTR;
WRITE_ONCE(queue.status, -EINTR);
queue.sleeper = current;
__set_current_state(TASK_INTERRUPTIBLE);