From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] bnxt_en: avoid string overflow for record->system_name Date: Mon, 13 Aug 2018 20:46:30 -0700 (PDT) Message-ID: <20180813.204630.1588025496006675499.davem@davemloft.net> References: <20180813212700.2681499-1-arnd@arndb.de> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: michael.chan@broadcom.com, vasundhara-v.volam@broadcom.com, scott.branden@broadcom.com, gospo@broadcom.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: arnd@arndb.de Return-path: In-Reply-To: <20180813212700.2681499-1-arnd@arndb.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Arnd Bergmann Date: Mon, 13 Aug 2018 23:26:54 +0200 > The utsname()->nodename string may be 64 bytes long, and it gets > copied without the trailing nul byte into the shorter record->system_name, > as gcc now warns: > > In file included from include/linux/bitmap.h:9, > from include/linux/ethtool.h:16, > from drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c:13: > In function 'strncpy', > inlined from 'bnxt_fill_coredump_record' at drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c:2863:2: > include/linux/string.h:254:9: error: '__builtin_strncpy' output truncated before terminating nul copying as many bytes from a string as its length [-Werror=stringop-truncation] > > Using strlcpy() at least avoids overflowing the destination buffer > and adds proper nul-termination. It may still truncate long names > though, which probably can't be solved here. > > Fixes: 6c5657d085ae ("bnxt_en: Add support for ethtool get dump.") > Signed-off-by: Arnd Bergmann Applied.