From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752325AbaEGCgO (ORCPT ); Tue, 6 May 2014 22:36:14 -0400 Received: from mga09.intel.com ([134.134.136.24]:13484 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751140AbaEGCgN (ORCPT ); Tue, 6 May 2014 22:36:13 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,1000,1389772800"; d="scan'208";a="507343935" From: Leon Ma To: akpm@linux-foundation.org, iamjoonsoo.kim@lge.com, n-horiguchi@ah.jp.nec.com, kirill.shutemov@linux.intel.com, gorcunov@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Leon Ma Subject: [PATCH] rmap: validate pointer in anon_vma_clone Date: Wed, 7 May 2014 10:32:09 +0800 Message-Id: <1399429930-5073-1-git-send-email-xindong.ma@intel.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If memory allocation failed in first loop, root will be NULL and will lead to kernel panic. Signed-off-by: Leon Ma --- mm/rmap.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index 9c3e773..6e53aed 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -246,8 +246,10 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src) avc = anon_vma_chain_alloc(GFP_NOWAIT | __GFP_NOWARN); if (unlikely(!avc)) { - unlock_anon_vma_root(root); - root = NULL; + if (!root) { + unlock_anon_vma_root(root); + root = NULL; + } avc = anon_vma_chain_alloc(GFP_KERNEL); if (!avc) goto enomem_failure; -- 1.7.9.5