linux-kernel - [PATCH v4 08/36] mm: introduce __GFP_NO_OBJ_EXT flag to selectively prevent slabobj

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240221194052.927623-9-surenb@google.com>
Date: Wed, 21 Feb 2024 11:40:21 -0800
From: Suren Baghdasaryan <surenb@...gle.com>
To: akpm@...ux-foundation.org
Cc: kent.overstreet@...ux.dev, mhocko@...e.com, vbabka@...e.cz, 
	hannes@...xchg.org, roman.gushchin@...ux.dev, mgorman@...e.de, 
	dave@...olabs.net, willy@...radead.org, liam.howlett@...cle.com, 
	penguin-kernel@...ove.sakura.ne.jp, corbet@....net, void@...ifault.com, 
	peterz@...radead.org, juri.lelli@...hat.com, catalin.marinas@....com, 
	will@...nel.org, arnd@...db.de, tglx@...utronix.de, mingo@...hat.com, 
	dave.hansen@...ux.intel.com, x86@...nel.org, peterx@...hat.com, 
	david@...hat.com, axboe@...nel.dk, mcgrof@...nel.org, masahiroy@...nel.org, 
	nathan@...nel.org, dennis@...nel.org, tj@...nel.org, muchun.song@...ux.dev, 
	rppt@...nel.org, paulmck@...nel.org, pasha.tatashin@...een.com, 
	yosryahmed@...gle.com, yuzhao@...gle.com, dhowells@...hat.com, 
	hughd@...gle.com, andreyknvl@...il.com, keescook@...omium.org, 
	ndesaulniers@...gle.com, vvvvvv@...gle.com, gregkh@...uxfoundation.org, 
	ebiggers@...gle.com, ytcoode@...il.com, vincent.guittot@...aro.org, 
	dietmar.eggemann@....com, rostedt@...dmis.org, bsegall@...gle.com, 
	bristot@...hat.com, vschneid@...hat.com, cl@...ux.com, penberg@...nel.org, 
	iamjoonsoo.kim@....com, 42.hyeyoo@...il.com, glider@...gle.com, 
	elver@...gle.com, dvyukov@...gle.com, shakeelb@...gle.com, 
	songmuchun@...edance.com, jbaron@...mai.com, rientjes@...gle.com, 
	minchan@...gle.com, kaleshsingh@...gle.com, surenb@...gle.com, 
	kernel-team@...roid.com, linux-doc@...r.kernel.org, 
	linux-kernel@...r.kernel.org, iommu@...ts.linux.dev, 
	linux-arch@...r.kernel.org, linux-fsdevel@...r.kernel.org, linux-mm@...ck.org, 
	linux-modules@...r.kernel.org, kasan-dev@...glegroups.com, 
	cgroups@...r.kernel.org
Subject: [PATCH v4 08/36] mm: introduce __GFP_NO_OBJ_EXT flag to selectively
 prevent slabobj_ext creation

Introduce __GFP_NO_OBJ_EXT flag in order to prevent recursive allocations
when allocating slabobj_ext on a slab.

Signed-off-by: Suren Baghdasaryan <surenb@...gle.com>
Reviewed-by: Kees Cook <keescook@...omium.org>
---
 include/linux/gfp_types.h | 11 +++++++++++
 mm/slub.c                 |  2 ++
 2 files changed, 13 insertions(+)

diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h
index 868c8fb1bbc1..e36e168d8cfd 100644
--- a/include/linux/gfp_types.h
+++ b/include/linux/gfp_types.h
@@ -52,6 +52,9 @@ enum {
 #endif
 #ifdef CONFIG_LOCKDEP
 	___GFP_NOLOCKDEP_BIT,
+#endif
+#ifdef CONFIG_SLAB_OBJ_EXT
+	___GFP_NO_OBJ_EXT_BIT,
 #endif
 	___GFP_LAST_BIT
 };
@@ -93,6 +96,11 @@ enum {
 #else
 #define ___GFP_NOLOCKDEP	0
 #endif
+#ifdef CONFIG_SLAB_OBJ_EXT
+#define ___GFP_NO_OBJ_EXT       BIT(___GFP_NO_OBJ_EXT_BIT)
+#else
+#define ___GFP_NO_OBJ_EXT       0
+#endif
 
 /*
  * Physical address zone modifiers (see linux/mmzone.h - low four bits)
@@ -133,12 +141,15 @@ enum {
  * node with no fallbacks or placement policy enforcements.
  *
  * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
+ *
+ * %__GFP_NO_OBJ_EXT causes slab allocation to have no object extension.
  */
 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
 #define __GFP_WRITE	((__force gfp_t)___GFP_WRITE)
 #define __GFP_HARDWALL   ((__force gfp_t)___GFP_HARDWALL)
 #define __GFP_THISNODE	((__force gfp_t)___GFP_THISNODE)
 #define __GFP_ACCOUNT	((__force gfp_t)___GFP_ACCOUNT)
+#define __GFP_NO_OBJ_EXT   ((__force gfp_t)___GFP_NO_OBJ_EXT)
 
 /**
  * DOC: Watermark modifiers
diff --git a/mm/slub.c b/mm/slub.c
index 76fb600fbc80..ca803b2949fc 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1899,6 +1899,8 @@ int alloc_slab_obj_exts(struct slab *slab, struct kmem_cache *s,
 	void *vec;
 
 	gfp &= ~OBJCGS_CLEAR_MASK;
+	/* Prevent recursive extension vector allocation */
+	gfp |= __GFP_NO_OBJ_EXT;
 	vec = kcalloc_node(objects, sizeof(struct slabobj_ext), gfp,
 			   slab_nid(slab));
 	if (!vec)
-- 
2.44.0.rc0.258.g7320e95886-goog