mm/slab_common.c: check kmem_create_cache flags are common

Verify that kmem_create_cache flags are not allocator specific.  It is
done before removing flags that are not available with the current
configuration.

The current kmem_cache_create removes incorrect flags but do not
validate the callers are using them right.  This change will ensure that
callers are not trying to create caches with flags that won't be used
because allocator specific.

Link: http://lkml.kernel.org/r/1478553075-120242-2-git-send-email-thgarnie@google.com
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/mm/slab.h b/mm/slab.h
index ceb7d70..699b072 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -142,8 +142,23 @@ static inline unsigned long kmem_cache_flags(unsigned long object_size,
 #define SLAB_CACHE_FLAGS (0)
 #endif
 
+/* Common flags available with current configuration */
 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
 
+/* Common flags permitted for kmem_cache_create */
+#define SLAB_FLAGS_PERMITTED (SLAB_CORE_FLAGS | \
+			      SLAB_RED_ZONE | \
+			      SLAB_POISON | \
+			      SLAB_STORE_USER | \
+			      SLAB_TRACE | \
+			      SLAB_CONSISTENCY_CHECKS | \
+			      SLAB_MEM_SPREAD | \
+			      SLAB_NOLEAKTRACE | \
+			      SLAB_RECLAIM_ACCOUNT | \
+			      SLAB_TEMPORARY | \
+			      SLAB_NOTRACK | \
+			      SLAB_ACCOUNT)
+
 int __kmem_cache_shutdown(struct kmem_cache *);
 void __kmem_cache_release(struct kmem_cache *);
 int __kmem_cache_shrink(struct kmem_cache *);