The patch titled
Subject: ipc/sem.c: prevent queue.status tearing in semop
has been added to the -mm tree. Its filename is
ipc-sem-prevent-queuestatus-tearing-in-semop.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ipc-sem-prevent-queuestatus-tearing-in-semop.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ipc-sem-prevent-queuestatus-tearing-in-semop.patch
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------------------------------------------------------
From: Davidlohr Bueso <dave@xxxxxxxxxxxx>
Subject: 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@xxxxxxxxxxxx
Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
Cc: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
diff -puN ipc/sem.c~ipc-sem-prevent-queuestatus-tearing-in-semop ipc/sem.c
--- a/ipc/sem.c~ipc-sem-prevent-queuestatus-tearing-in-semop
+++ a/ipc/sem.c
@@ -2118,7 +2118,7 @@ static long do_semtimedop(int semid, str
}
do {
- queue.status = -EINTR;
+ WRITE_ONCE(queue.status, -EINTR);
queue.sleeper = current;
__set_current_state(TASK_INTERRUPTIBLE);
_
Patches currently in -mm which might be from dave@xxxxxxxxxxxx are
ipc-sem-prevent-queuestatus-tearing-in-semop.patch
ipc-drop-ipc_lock.patch
lib-rhashtable-simplify-bucket_table_alloc.patch
lib-rhashtable-guarantee-initial-hashtable-allocation.patch
ipc-get-rid-of-ids-tables_initialized-hack.patch
ipc-simplify-ipc-initialization.patch
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