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authorDavidlohr Bueso <dave@stgolabs.net>2018-07-26 16:37:19 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-07-26 19:38:03 -0700
commitf075faa300acc4f6301e348acde0a4580ed5f77c (patch)
treef2463b201b1785fd6af3cdd52bcf932267a85e92 /ipc
parent15d36fecd0bdc7510b70a0e5ec6671140b3fce0c (diff)
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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/20180717052654.676-1-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'ipc')
-rw-r--r--ipc/sem.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/ipc/sem.c b/ipc/sem.c
index 5af1943ad782..76e95e4f3aa2 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -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);