linux-kernel - [PATCH] SLAB: Record actual last user of freed objects.

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-next>] [day] [month] [year] [list]

Date:	Thu,  2 Jun 2011 00:16:42 -0700
From:	Suleiman Souhlal <ssouhlal@...eBSD.org>
To:	penberg@...nel.org
Cc:	suleiman@...gle.com, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, cl@...ux-foundation.org, mpm@...enic.com,
	Suleiman Souhlal <ssouhlal@...eBSD.org>
Subject: [PATCH] SLAB: Record actual last user of freed objects.

Currently, when using CONFIG_DEBUG_SLAB, we put in kfree() or
kmem_cache_free() as the last user of free objects, which is not
very useful, so change it to the caller of those functions instead.

Signed-off-by: Suleiman Souhlal <suleiman@...gle.com>
---
 mm/slab.c |    9 +++++----
 1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/mm/slab.c b/mm/slab.c
index 98f114d..615e76c 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3603,13 +3603,14 @@ free_done:
  * Release an obj back to its cache. If the obj has a constructed state, it must
  * be in this state _before_ it is released.  Called with disabled ints.
  */
-static inline void __cache_free(struct kmem_cache *cachep, void *objp)
+static inline void __cache_free(struct kmem_cache *cachep, void *objp,
+    void *caller)
 {
 	struct array_cache *ac = cpu_cache_get(cachep);
 
 	check_irq_off();
 	kmemleak_free_recursive(objp, cachep->flags);
-	objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0));
+	objp = cache_free_debugcheck(cachep, objp, caller);
 
 	kmemcheck_slab_free(cachep, objp, obj_size(cachep));
 
@@ -3800,7 +3801,7 @@ void kmem_cache_free(struct kmem_cache *cachep, void *objp)
 	debug_check_no_locks_freed(objp, obj_size(cachep));
 	if (!(cachep->flags & SLAB_DEBUG_OBJECTS))
 		debug_check_no_obj_freed(objp, obj_size(cachep));
-	__cache_free(cachep, objp);
+	__cache_free(cachep, objp, __builtin_return_address(0));
 	local_irq_restore(flags);
 
 	trace_kmem_cache_free(_RET_IP_, objp);
@@ -3830,7 +3831,7 @@ void kfree(const void *objp)
 	c = virt_to_cache(objp);
 	debug_check_no_locks_freed(objp, obj_size(c));
 	debug_check_no_obj_freed(objp, obj_size(c));
-	__cache_free(c, (void *)objp);
+	__cache_free(c, (void *)objp, __builtin_return_address(0));
 	local_irq_restore(flags);
 }
 EXPORT_SYMBOL(kfree);
-- 
1.7.3.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/