Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932427AbaJIVGw (ORCPT ); Thu, 9 Oct 2014 17:06:52 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:59074 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932400AbaJIVGq (ORCPT ); Thu, 9 Oct 2014 17:06:46 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: David Rientjes , Pekka Enberg , Joonsoo Kim , Andrew Morton , Linus Torvalds , Kamal Mostafa Subject: [PATCH 3.13 145/163] mm, slab: initialize object alignment on cache creation Date: Thu, 9 Oct 2014 14:02:50 -0700 Message-Id: <1412888588-26755-146-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1412888588-26755-1-git-send-email-kamal@canonical.com> References: <1412888588-26755-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11.9 -stable review patch. If anyone has any objections, please let me know. ------------------ From: David Rientjes commit d4a5fca592b9ab52b90bb261a90af3c8f53be011 upstream. Since commit 4590685546a3 ("mm/sl[aou]b: Common alignment code"), the "ralign" automatic variable in __kmem_cache_create() may be used as uninitialized. The proper alignment defaults to BYTES_PER_WORD and can be overridden by SLAB_RED_ZONE or the alignment specified by the caller. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=85031 Signed-off-by: David Rientjes Reported-by: Andrei Elovikov Acked-by: Christoph Lameter Cc: Pekka Enberg Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Kamal Mostafa --- mm/slab.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) diff --git a/mm/slab.c b/mm/slab.c index eb043bf..f985e8f 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -2139,7 +2139,8 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp) int __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags) { - size_t left_over, freelist_size, ralign; + size_t left_over, freelist_size; + size_t ralign = BYTES_PER_WORD; gfp_t gfp; int err; size_t size = cachep->size; @@ -2172,14 +2173,6 @@ __kmem_cache_create (struct kmem_cache *cachep, unsigned long flags) size &= ~(BYTES_PER_WORD - 1); } - /* - * Redzoning and user store require word alignment or possibly larger. - * Note this will be overridden by architecture or caller mandated - * alignment if either is greater than BYTES_PER_WORD. - */ - if (flags & SLAB_STORE_USER) - ralign = BYTES_PER_WORD; - if (flags & SLAB_RED_ZONE) { ralign = REDZONE_ALIGN; /* If redzoning, ensure that the second redzone is suitably -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/