From bd8d57fb7e25e9fcf67a9eef5fa13aabe2016e07 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 6 Dec 2018 13:52:13 -0300 Subject: [PATCH] perf parse-events: Fix unchecked usage of strncpy() 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 59be346..920e1e6 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -2462,7 +2462,7 @@ restart: 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) -- 2.7.4