From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964866Ab1LPTxE (ORCPT ); Fri, 16 Dec 2011 14:53:04 -0500 Received: from cantor2.suse.de ([195.135.220.15]:45201 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760640Ab1LPTv2 (ORCPT ); Fri, 16 Dec 2011 14:51:28 -0500 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Dec 16 11:42:09 2011 Message-Id: <20111216194209.042369367@clark.kroah.org> User-Agent: quilt/0.50-24.1 Date: Fri, 16 Dec 2011 11:40:21 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Mel Gorman , David Rientjes Subject: [14/45] mm: vmalloc: check for page allocation failure before vmlist insertion In-Reply-To: <20111216194603.GA15028@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mel Gorman commit 1368edf0647ac112d8cfa6ce47257dc950c50f5c upstream. Commit f5252e00 ("mm: avoid null pointer access in vm_struct via /proc/vmallocinfo") adds newly allocated vm_structs to the vmlist after it is fully initialised. Unfortunately, it did not check that __vmalloc_area_node() successfully populated the area. In the event of allocation failure, the vmalloc area is freed but the pointer to freed memory is inserted into the vmlist leading to a a crash later in get_vmalloc_info(). This patch adds a check for ____vmalloc_area_node() failure within __vmalloc_node_range. It does not use "goto fail" as in the previous error path as a warning was already displayed by __vmalloc_area_node() before it called vfree in its failure path. Credit goes to Luciano Chavez for doing all the real work of identifying exactly where the problem was. Signed-off-by: Mel Gorman Reported-by: Luciano Chavez Tested-by: Luciano Chavez Reviewed-by: Rik van Riel Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/vmalloc.c | 2 ++ 1 file changed, 2 insertions(+) --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1648,6 +1648,8 @@ void *__vmalloc_node_range(unsigned long return NULL; addr = __vmalloc_area_node(area, gfp_mask, prot, node, caller); + if (!addr) + return NULL; /* * In this function, newly allocated vm_struct is not added