From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753609Ab3AGDmp (ORCPT ); Sun, 6 Jan 2013 22:42:45 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:59480 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753567Ab3AGDmn (ORCPT ); Sun, 6 Jan 2013 22:42:43 -0500 X-IronPort-AV: E=Sophos;i="4.84,421,1355068800"; d="scan'208";a="6533621" From: Lin Feng To: akpm@linux-foundation.org, tj@kernel.org Cc: mingo@kernel.org, yinghai@kernel.org, liwanp@linux.vnet.ibm.com, benh@kernel.crashing.org, tangchen@cn.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Lin Feng Subject: [PATCH v2] mm: memblock: fix wrong memmove size in memblock_merge_regions() Date: Mon, 7 Jan 2013 11:41:36 +0800 Message-Id: <1357530096-28548-1-git-send-email-linfeng@cn.fujitsu.com> X-Mailer: git-send-email 1.7.11.7 X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/01/07 11:42:12, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/01/07 11:42:13, Serialize complete at 2013/01/07 11:42:13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The memmove span covers from (next+1) to the end of the array, and the index of next is (i+1), so the index of (next+1) is (i+2). So the size of remaining array elements is (type->cnt - (i + 2)). Cc: Tejun Heo Reviewed-by: Wanpeng Li Signed-off-by: Lin Feng --- ChangeLog v1->v2: - Add a comment pointed out by Tejun. --- mm/memblock.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/memblock.c b/mm/memblock.c index 6259055..88adc8a 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -314,7 +314,8 @@ static void __init_memblock memblock_merge_regions(struct memblock_type *type) } this->size += next->size; - memmove(next, next + 1, (type->cnt - (i + 1)) * sizeof(*next)); + /* move forward from next + 1, index of which is i + 2 */ + memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next)); type->cnt--; } } -- 1.7.11.7