From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752358AbcCIG0k (ORCPT ); Wed, 9 Mar 2016 01:26:40 -0500 Received: from scadrial.mjdsystems.ca ([198.100.154.185]:32943 "EHLO scadrial.mjdsystems.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751107AbcCIG0f (ORCPT ); Wed, 9 Mar 2016 01:26:35 -0500 X-Greylist: delayed 580 seconds by postgrey-1.27 at vger.kernel.org; Wed, 09 Mar 2016 01:26:35 EST From: Matthew Dawson To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Subject: [PATCH] mm/mempool: Avoid KASAN marking mempool posion checks as use-after-free Date: Wed, 9 Mar 2016 01:16:19 -0500 Message-Id: <1457504179-18942-1-git-send-email-matthew@mjdsystems.ca> X-Mailer: git-send-email 2.7.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When removing an element from the mempool, mark it as unpoisoned in KASAN before verifying its contents for SLUB/SLAB debugging. Otherwise KASAN will flag the reads checking the element use-after-free writes as use-after-free reads. Signed-off-by: Matthew Dawson --- mm/mempool.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mempool.c b/mm/mempool.c index 004d42b..7924f4f 100644 --- a/mm/mempool.c +++ b/mm/mempool.c @@ -135,8 +135,8 @@ static void *remove_element(mempool_t *pool) void *element = pool->elements[--pool->curr_nr]; BUG_ON(pool->curr_nr < 0); - check_element(pool, element); kasan_unpoison_element(pool, element); + check_element(pool, element); return element; } -- 2.7.1