From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: [PATCH 67/75] perf parse-events: Fix unchecked usage of strncpy() Date: Thu, 6 Dec 2018 18:25:54 -0300 Message-ID: <20181206212602.20474-68-acme@kernel.org> References: <20181206212602.20474-1-acme@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20181206212602.20474-1-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: Ingo Molnar Cc: Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Arnaldo Carvalho de Melo , Adrian Hunter , Jiri Olsa , Namhyung Kim List-Id: linux-perf-users.vger.kernel.org From: Arnaldo Carvalho de Melo The strncpy() function may leave the destination string buffer unterminated, better use strlcpy() that we have a __weak fallback implementation for systems without it. This fixes this warning on an Alpine Linux Edge system with gcc 8.2: util/parse-events.c: In function 'print_symbol_events': util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation] strncpy(name, syms->symbol, MAX_NAME_LEN); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In function 'print_symbol_events.constprop', inlined from 'print_events' at util/parse-events.c:2508:2: util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation] strncpy(name, syms->symbol, MAX_NAME_LEN); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In function 'print_symbol_events.constprop', inlined from 'print_events' at util/parse-events.c:2511:2: util/parse-events.c:2465:4: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation] strncpy(name, syms->symbol, MAX_NAME_LEN); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Fixes: 947b4ad1d198 ("perf list: Fix max event string size") Link: https://lkml.kernel.org/n/tip-b663e33bm6x8hrkie4uxh7u2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/parse-events.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 59be3466d64d..920e1e6551dd 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -2462,7 +2462,7 @@ void print_symbol_events(const char *event_glob, unsigned type, if (!name_only && strlen(syms->alias)) snprintf(name, MAX_NAME_LEN, "%s OR %s", syms->symbol, syms->alias); else - strncpy(name, syms->symbol, MAX_NAME_LEN); + strlcpy(name, syms->symbol, MAX_NAME_LEN); evt_list[evt_i] = strdup(name); if (evt_list[evt_i] == NULL) -- 2.19.2