+ mm-slub-avoid-recursive-loop-with-kmemleak.patch added to mm-unstable branch

+ mm-slub-avoid-recursive-loop-with-kmemleak.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/slub: avoid recursive loop with kmemleak
has been added to the -mm mm-unstable branch.  Its filename is
     mm-slub-avoid-recursive-loop-with-kmemleak.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-slub-avoid-recursive-loop-with-kmemleak.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Kees Cook <keescook@chromium.org>
Subject: mm/slub: avoid recursive loop with kmemleak
Date: Thu, 25 Apr 2024 13:55:23 -0700

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.

Link: https://lkml.kernel.org/r/20240425205516.work.220-kees@kernel.org
Fixes: 279bb991b4d9 ("mm/slab: add allocation accounting into slab allocation and free paths")
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kmemleak.c |    4 ++--
 mm/slub.c     |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

--- a/mm/kmemleak.c~mm-slub-avoid-recursive-loop-with-kmemleak
+++ a/mm/kmemleak.c
@@ -463,7 +463,7 @@ static struct kmemleak_object *mem_pool_
 
 	/* 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
 	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) {
--- a/mm/slub.c~mm-slub-avoid-recursive-loop-with-kmemleak
+++ a/mm/slub.c
@@ -2018,7 +2018,7 @@ prepare_slab_obj_exts_hook(struct kmem_c
 	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)
_

Patches currently in -mm which might be from keescook@chromium.org are

alloc_tag-tighten-file-permissions-on-proc-allocinfo.patch
mm-slub-avoid-recursive-loop-with-kmemleak.patch