From: Arnaldo Carvalho de Melo acme@redhat.com
commit 5192bde7d98c99f2cd80225649e3c2e7493722f7 upstream.
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/header.c: In function 'perf_event__synthesize_event_update_name': util/header.c:3625:2: error: 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length [-Werror=stringop-truncation] strncpy(ev->data, evsel->name, len); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ util/header.c:3618:15: note: length computed here size_t len = strlen(evsel->name); ^~~~~~~~~~~~~~~~~~~
Cc: Adrian Hunter adrian.hunter@intel.com Cc: Jiri Olsa jolsa@kernel.org Cc: Namhyung Kim namhyung@kernel.org Fixes: a6e5281780d1 ("perf tools: Add event_update event unit type") Link: https://lkml.kernel.org/n/tip-wycz66iy8dl2z3yifgqf894p@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- tools/perf/util/header.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -3171,7 +3171,7 @@ perf_event__synthesize_event_update_name if (ev == NULL) return -ENOMEM;
- strncpy(ev->data, evsel->name, len); + strlcpy(ev->data, evsel->name, len + 1); err = process(tool, (union perf_event*) ev, NULL, NULL); free(ev); return err;