From d177e25c9c3a16c06ce697daa6c6720f2800cfbd Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 6 Dec 2018 10:49:46 -0300 Subject: [PATCH] perf dso: Fix unchecked usage of strncpy() [ Upstream commit fca5085c15255bbde203b7322c15f07ebb12f63e ] 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: In function 'decompress_kmodule', inlined from 'dso__decompress_kmodule_fd' at util/dso.c:305:9: util/dso.c:298:3: error: 'strncpy' destination unchanged after copying no bytes [-Werror=stringop-truncation] strncpy(pathname, tmpbuf, len); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ CC /tmp/build/perf/util/values.o CC /tmp/build/perf/util/debug.o cc1: all warnings being treated as errors Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Fixes: c9a8a6131fb6 ("perf tools: Move the temp file processing into decompress_kmodule") Link: https://lkml.kernel.org/n/tip-tl2hdxj64tt4k8btbi6a0ugw@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/dso.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c index bbed90e..cee717a 100644 --- a/tools/perf/util/dso.c +++ b/tools/perf/util/dso.c @@ -295,7 +295,7 @@ static int decompress_kmodule(struct dso *dso, const char *name, unlink(tmpbuf); if (pathname && (fd >= 0)) - strncpy(pathname, tmpbuf, len); + strlcpy(pathname, tmpbuf, len); return fd; } -- 2.7.4