mm/slub: fix redzoning for small allocations

[sfrench/cifs-2.6.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index f91d9fe7d0d8f838ac4070a7485b28b91e83c026..f58cfd4565489ea7c9d66c2fdba8068f8c157a24 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -3734,15 +3734,17 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
         */
        s->inuse = size;
 
-       if (((flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) ||
-               s->ctor)) {
+       if ((flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) ||
+           ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) ||
+           s->ctor) {
                /*
                 * Relocate free pointer after the object if it is not
                 * permitted to overwrite the first word of the object on
                 * kmem_cache_free.
                 *
                 * This is the case if we do RCU, have a constructor or
-                * destructor or are poisoning the objects.
+                * destructor, are poisoning the objects, or are
+                * redzoning an object smaller than sizeof(void *).
                 *
                 * The assumption that s->offset >= s->inuse means free
                 * pointer is outside of the object is used in the