[PATCH] mm/slub: Avoid recursive loop with kmemleak

[Kees Cook <keescook@chromium.org>]

The system will immediate fill up stack and crash when both
CONFIG_DEBUG_KMEMLEAK and CONFIG_MEM_ALLOC_PROFILING are enabled.
Avoid allocation tagging of kmemleak caches, otherwise recursive
allocation tracking occurs.

Fixes: 279bb991b4d9 ("mm/slab: add allocation accounting into slab allocation and free paths")
Signed-off-by: Kees Cook <keescook@chromium.org>
---
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
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>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: linux-mm@kvack.org
---
 mm/kmemleak.c | 4 ++--
 mm/slub.c     | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index c55c2cbb6837..fdcf01f62202 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -463,7 +463,7 @@ static struct kmemleak_object *mem_pool_alloc(gfp_t gfp)
 
 	/* try the slab allocator first */
 	if (object_cache) {
-		object = kmem_cache_alloc(object_cache, gfp_kmemleak_mask(gfp));
+		object = kmem_cache_alloc_noprof(object_cache, gfp_kmemleak_mask(gfp));
 		if (object)
 			return object;
 	}
@@ -947,7 +947,7 @@ static void add_scan_area(unsigned long ptr, size_t size, gfp_t gfp)
 	untagged_objp = (unsigned long)kasan_reset_tag((void *)object->pointer);
 
 	if (scan_area_cache)
-		area = kmem_cache_alloc(scan_area_cache, gfp_kmemleak_mask(gfp));
+		area = kmem_cache_alloc_noprof(scan_area_cache, gfp_kmemleak_mask(gfp));
 
 	raw_spin_lock_irqsave(&object->lock, flags);
 	if (!area) {
diff --git a/mm/slub.c b/mm/slub.c
index a94a0507e19c..9ae032ed17ed 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2016,7 +2016,7 @@ prepare_slab_obj_exts_hook(struct kmem_cache *s, gfp_t flags, void *p)
 	if (!p)
 		return NULL;
 
-	if (s->flags & SLAB_NO_OBJ_EXT)
+	if (s->flags & (SLAB_NO_OBJ_EXT | SLAB_NOLEAKTRACE))
 		return NULL;
 
 	if (flags & __GFP_NO_OBJ_EXT)
-- 
2.34.1