The patch titled
Subject: slab: alien caches must not be initialized if the allocation of the alien cache failed
has been removed from the -mm tree. Its filename was
slab-alien-caches-must-not-be-initialized-if-the-allocation-of-the-alien-cache-failed.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Christoph Lameter <cl@xxxxxxxxx>
Subject: 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@xxxxxxxxxxxxxxxxxxx
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@xxxxxxxxx>
Reported-by: syzbot+d6ed4ec679652b4fd4e4@xxxxxxxxxxxxxxxxxxxxxxxxx
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/slab.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/mm/slab.c~slab-alien-caches-must-not-be-initialized-if-the-allocation-of-the-alien-cache-failed
+++ a/mm/slab.c
@@ -666,8 +666,10 @@ static struct alien_cache *__alloc_alien
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;
}
_
Patches currently in -mm which might be from cl@xxxxxxxxx are
