diff options
| author | Christoph Lameter <cl@linux.com> | 2019-01-09 00:23:00 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-01-09 02:15:11 +0100 |
| commit | 09c2e76ed734a1d36470d257a778aaba28e86531 (patch) | |
| tree | 2f951b3f6daa70b8c3f2c6371b5c2c62d6bd6455 /mm | |
| parent | fork, memcg: fix cached_stacks case (diff) | |
| download | linux-09c2e76ed734a1d36470d257a778aaba28e86531.tar.xz linux-09c2e76ed734a1d36470d257a778aaba28e86531.zip | |
slab: alien caches must not be initialized if the allocation of the alien cache failed
Callers of __alloc_alien() check for NULL. We must do the same check in
__alloc_alien_cache to avoid NULL pointer dereferences on allocation
failures.
Link: http://lkml.kernel.org/r/010001680f42f192-82b4e12e-1565-4ee0-ae1f-1e98974906aa-000000@email.amazonses.com
Fixes: 49dfc304ba241 ("slab: use the lock on alien_cache, instead of the lock on array_cache")
Fixes: c8522a3a5832b ("Slab: introduce alloc_alien")
Signed-off-by: Christoph Lameter <cl@linux.com>
Reported-by: syzbot+d6ed4ec679652b4fd4e4@syzkaller.appspotmail.com
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/slab.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/mm/slab.c b/mm/slab.c index 73fe23e649c9..78eb8c5bf4e4 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -666,8 +666,10 @@ static struct alien_cache *__alloc_alien_cache(int node, int entries, struct alien_cache *alc = NULL; alc = kmalloc_node(memsize, gfp, node); - init_arraycache(&alc->ac, entries, batch); - spin_lock_init(&alc->lock); + if (alc) { + init_arraycache(&alc->ac, entries, batch); + spin_lock_init(&alc->lock); + } return alc; } |