From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH] [pktgen] Fix string truncation warnings Date: Mon, 7 Jan 2019 12:22:25 -0800 Message-ID: <20190107202225.4249-1-sthemmin@microsoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Stephen Hemminger To: dev@dpdk.org Return-path: Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) by dpdk.org (Postfix) with ESMTP id C2A691B505 for ; Mon, 7 Jan 2019 21:22:35 +0100 (CET) Received: by mail-pl1-f169.google.com with SMTP id p8so684136plo.2 for ; Mon, 07 Jan 2019 12:22:35 -0800 (PST) List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" From: Stephen Hemminger The strncatf macro will cause warnings with latest GCC if the sizeof the destination buffer is smaller than the temporary buffer. Resolve by adjusting buffer sizes. Such as: git/pktgen-dpdk/app/pktgen-capture.c: In function ‘pktgen_set_capture’: git/pktgen-dpdk/app/pktgen-log.h:114:3: error: ‘strncat’ output may be truncated copying between 0 and 255 bytes from a string of length 1022 [-Werror=stringop-truncation] strncat(dest, _buff, sizeof(dest) - strlen(dest) - 1); \ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ git/pktgen-dpdk/app/pktgen-capture.c:246:7: note: in expansion of macro ‘strncatf’ strncatf(status, "%d%%", pct); ^~~~~~~~ cc1: all warnings being treated as errors Signed-off-by: Stephen Hemminger --- app/pktgen-capture.c | 2 +- app/pktgen-log.h | 10 +++++----- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/app/pktgen-capture.c b/app/pktgen-capture.c index aee4ff9bd650..0f3f42bdc488 100644 --- a/app/pktgen-capture.c +++ b/app/pktgen-capture.c @@ -200,7 +200,7 @@ found_rx_lid: size_t mem_dumped = 0; unsigned int pct = 0; - char status[256]; + char status[1024]; sprintf( status, "\r Dumping ~%.2fMB of captured data to disk: 0%%", diff --git a/app/pktgen-log.h b/app/pktgen-log.h index 46e347b72b3f..8d132d88c748 100644 --- a/app/pktgen-log.h +++ b/app/pktgen-log.h @@ -108,11 +108,11 @@ extern "C" { * arguments. It formats the string and appends it to the existing string, while * avoiding possible buffer overruns. */ -#define strncatf(dest, fmt, ...) do { \ - char _buff[1024]; \ - snprintf(_buff, sizeof(_buff), fmt, ## __VA_ARGS__); \ - strncat(dest, _buff, sizeof(dest) - strlen(dest) - 1); \ -} while (0) +#define strncatf(dest, fmt, ...) do { \ + char _buff[1023]; \ + snprintf(_buff, sizeof(_buff), fmt, ## __VA_ARGS__); \ + strncat(dest, _buff, sizeof(dest) - strlen(dest) - 1); \ + } while (0) /* Initialize log data structures */ void pktgen_init_log(void); -- 2.20.1