From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753712AbdHXVBl (ORCPT ); Thu, 24 Aug 2017 17:01:41 -0400 Received: from shards.monkeyblade.net ([184.105.139.130]:53042 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753201AbdHXVBk (ORCPT ); Thu, 24 Aug 2017 17:01:40 -0400 Date: Thu, 24 Aug 2017 14:01:37 -0700 (PDT) Message-Id: <20170824.140137.2014331371813442270.davem@davemloft.net> To: arnd@arndb.de Cc: harish.patil@cavium.com, manish.chopra@cavium.com, Dept-GELinuxNICDev@cavium.com, stable@vger.kernel.org, keescook@chromium.org, gustavo@embeddedor.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [net-next] qlge: avoid memcpy buffer overflow From: David Miller In-Reply-To: <20170823135958.1379527-1-arnd@arndb.de> References: <20170823135958.1379527-1-arnd@arndb.de> X-Mailer: Mew version 6.7 on Emacs 25.2 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Thu, 24 Aug 2017 14:01:40 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann Date: Wed, 23 Aug 2017 15:59:49 +0200 > gcc-8.0.0 (snapshot) points out that we copy a variable-length string > into a fixed length field using memcpy() with the destination length, > and that ends up copying whatever follows the string: > > inlined from 'ql_core_dump' at drivers/net/ethernet/qlogic/qlge/qlge_dbg.c:1106:2: > drivers/net/ethernet/qlogic/qlge/qlge_dbg.c:708:2: error: 'memcpy' reading 15 bytes from a region of size 14 [-Werror=stringop-overflow=] > memcpy(seg_hdr->description, desc, (sizeof(seg_hdr->description)) - 1); > > Changing it to use strncpy() will instead zero-pad the destination, > which seems to be the right thing to do here. > > The bug is probably harmless, but it seems like a good idea to address > it in stable kernels as well, if only for the purpose of building with > gcc-8 without warnings. > > Cc: stable@vger.kernel.org Please don't use explicit stable CC:'ing for networking changes. > Fixes: a61f80261306 ("qlge: Add ethtool register dump function.") > Signed-off-by: Arnd Bergmann Applied to 'net' and queued up for -stable, thanks.