Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933127AbbFIMGS (ORCPT ); Tue, 9 Jun 2015 08:06:18 -0400 Received: from mail-pd0-f171.google.com ([209.85.192.171]:34542 "EHLO mail-pd0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932833AbbFIMF5 (ORCPT ); Tue, 9 Jun 2015 08:05:57 -0400 From: Sergey Senozhatsky To: Andrew Morton Cc: Minchan Kim , Christoph Lameter , Pekka Enberg , Joonsoo Kim , Michal Hocko , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org, sergey.senozhatsky.work@gmail.com, Sergey Senozhatsky Subject: [RFC][PATCH 3/5] mm/dmapool: allow NULL `pool' pointer in dma_pool_destroy() Date: Tue, 9 Jun 2015 21:04:51 +0900 Message-Id: <1433851493-23685-4-git-send-email-sergey.senozhatsky@gmail.com> X-Mailer: git-send-email 2.4.3.368.g7974889 In-Reply-To: <1433851493-23685-1-git-send-email-sergey.senozhatsky@gmail.com> References: <1433851493-23685-1-git-send-email-sergey.senozhatsky@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1245 Lines: 43 dma_pool_destroy() does not tolerate a NULL dma_pool pointer argument and performs a NULL-pointer dereference. This requires additional attention and effort from developers/reviewers and forces all dma_pool_destroy() callers to do a NULL check if (pool) dma_pool_destroy(pool); Or, otherwise, be invalid dma_pool_destroy() users. Tweak dma_pool_destroy() and NULL-check the pointer there. Proposed by Andrew Morton. Signed-off-by: Sergey Senozhatsky Reported-by: Andrew Morton LKML-reference: https://lkml.org/lkml/2015/6/8/583 --- mm/dmapool.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/dmapool.c b/mm/dmapool.c index fd5fe43..5f2cffc 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -271,6 +271,9 @@ void dma_pool_destroy(struct dma_pool *pool) { bool empty = false; + if (unlikely(!pool)) + return; + mutex_lock(&pools_reg_lock); mutex_lock(&pools_lock); list_del(&pool->pools); -- 2.4.3.368.g7974889 -- 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/