From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752696AbdKAVuC (ORCPT ); Wed, 1 Nov 2017 17:50:02 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:35327 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934108AbdKAV2F (ORCPT ); Wed, 1 Nov 2017 17:28:05 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Arnd Bergmann , "David S . Miller" , Willy Tarreau Subject: [PATCH 3.10 124/139] qlge: avoid memcpy buffer overflow Date: Wed, 1 Nov 2017 22:26:49 +0100 Message-Id: <1509571624-5001-25-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1509571624-5001-1-git-send-email-w@1wt.eu> References: <1509571159-4405-1-git-send-email-w@1wt.eu> <1509571624-5001-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnd Bergmann commit e58f95831e7468d25eb6e41f234842ecfe6f014f upstream. 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. Fixes: a61f80261306 ("qlge: Add ethtool register dump function.") Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller Signed-off-by: Willy Tarreau --- drivers/net/ethernet/qlogic/qlge/qlge_dbg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/qlogic/qlge/qlge_dbg.c b/drivers/net/ethernet/qlogic/qlge/qlge_dbg.c index 10093f0..00a8058 100644 --- a/drivers/net/ethernet/qlogic/qlge/qlge_dbg.c +++ b/drivers/net/ethernet/qlogic/qlge/qlge_dbg.c @@ -724,7 +724,7 @@ static void ql_build_coredump_seg_header( seg_hdr->cookie = MPI_COREDUMP_COOKIE; seg_hdr->segNum = seg_number; seg_hdr->segSize = seg_size; - memcpy(seg_hdr->description, desc, (sizeof(seg_hdr->description)) - 1); + strncpy(seg_hdr->description, desc, (sizeof(seg_hdr->description)) - 1); } /* -- 2.8.0.rc2.1.gbe9624a