[PATCH 5.10 125/154] mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag

From: Greg Kroah-Hartman
Date: Wed Nov 24 2021 - 08:39:08 EST


From: Rustam Kovhaev <rkovhaev@xxxxxxxxx>

commit 34dbc3aaf5d9e89ba6cc5e24add9458c21ab1950 upstream.

When kmemleak is enabled for SLOB, system does not boot and does not
print anything to the console. At the very early stage in the boot
process we hit infinite recursion from kmemleak_init() and eventually
kernel crashes.

kmemleak_init() specifies SLAB_NOLEAKTRACE for KMEM_CACHE(), but
kmem_cache_create_usercopy() removes it because CACHE_CREATE_MASK is not
valid for SLOB.

Let's fix CACHE_CREATE_MASK and make kmemleak work with SLOB

Link: https://lkml.kernel.org/r/20211115020850.3154366-1-rkovhaev@xxxxxxxxx
Fixes: d8843922fba4 ("slab: Ignore internal flags in cache creation")
Signed-off-by: Rustam Kovhaev <rkovhaev@xxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Glauber Costa <glommer@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/slab.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/slab.h
+++ b/mm/slab.h
@@ -147,7 +147,7 @@ static inline slab_flags_t kmem_cache_fl
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
SLAB_TEMPORARY | SLAB_ACCOUNT)
#else
-#define SLAB_CACHE_FLAGS (0)
+#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE)
#endif

/* Common flags available with current configuration */