slub: Extend init_on_alloc to slab caches with constructors

Signed-off-by: Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr> Signed-off-by: Levente Polyak <levente@leventepolyak.net>
anthraxx · Mar 23, 2022 · 59a2f4f · 59a2f4f
1 parent 776e69a
commit 59a2f4f
Show file tree

Hide file tree

Showing 2 changed files with 16 additions and 2 deletions.
diff --git a/mm/slab.h b/mm/slab.h
@@ -627,8 +627,10 @@ static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
 static inline bool slab_want_init_on_alloc(gfp_t flags, struct kmem_cache *c)
 {
 	if (static_branch_unlikely(&init_on_alloc)) {
+#ifndef CONFIG_SLUB
 		if (c->ctor)
 			return false;
+#endif
 		if (c->flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON))
 			return flags & __GFP_ZERO;
 		return true;

diff --git a/mm/slub.c b/mm/slub.c
@@ -2967,8 +2967,14 @@ static __always_inline void *slab_alloc_node(struct kmem_cache *s,
 		if (s->ctor)
 			s->ctor(object);
 		kasan_poison_object_data(s, object);
-	} else if (unlikely(slab_want_init_on_alloc(gfpflags, s)) && object)
+	} else if (unlikely(slab_want_init_on_alloc(gfpflags, s)) && object) {
 		memset(object, 0, s->object_size);
+		if (s->ctor) {
+			kasan_unpoison_object_data(s, object);
+			s->ctor(object);
+			kasan_poison_object_data(s, object);
+		}
+	}
 
 	if (object) {
 		check_canary(s, object, s->random_inactive);
@@ -3430,8 +3436,14 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
 	} else if (unlikely(slab_want_init_on_alloc(flags, s))) {
 		int j;
 
-		for (j = 0; j < i; j++)
+		for (j = 0; j < i; j++) {
 			memset(p[j], 0, s->object_size);
+			if (s->ctor) {
+				kasan_unpoison_object_data(s, p[j]);
+				s->ctor(p[j]);
+				kasan_poison_object_data(s, p[j]);
+			}
+		}
 	}
 
 	for (k = 0; k < i; k++) {