From 9d5f0c36438eeae7566ca383b2b673179e3cc613 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 18 Jan 2022 09:02:43 -0300 Subject: [PATCH] perf machine: Use path__join() to compose a path instead of snprintf(dir, '/', filename) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Its more intention revealing, and if we're interested in the odd cases where this may end up truncating we can do debug checks at one centralized place. Motivation, of all the container builds, fedora rawhide started complaining of: util/machine.c: In function ‘machine__create_modules’: util/machine.c:1419:50: error: ‘%s’ directive output may be truncated writing up to 255 bytes into a region of size between 0 and 4095 [-Werror=format-truncation=] 1419 | snprintf(path, sizeof(path), "%s/%s", dir_name, dent->d_name); | ^~ In file included from /usr/include/stdio.h:894, from util/branch.h:9, from util/callchain.h:8, from util/machine.c:7: In function ‘snprintf’, inlined from ‘maps__set_modules_path_dir’ at util/machine.c:1419:3, inlined from ‘machine__set_modules_path’ at util/machine.c:1473:9, inlined from ‘machine__create_modules’ at util/machine.c:1519:7: /usr/include/bits/stdio2.h:71:10: note: ‘__builtin___snprintf_chk’ output between 2 and 4352 bytes into a destination of size 4096 There are other places where we should use path__join(), but lets get rid of this one first. Cc: Adrian Hunter Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Acked-by: Ian Rogers Link: Link: https://lore.kernel.org/r/YebZKjwgfdOz0lAs@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/machine.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 3901440aeff9..f70ba56912d4 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -16,6 +16,7 @@ #include "map_symbol.h" #include "branch.h" #include "mem-events.h" +#include "path.h" #include "srcline.h" #include "symbol.h" #include "sort.h" @@ -1416,7 +1417,7 @@ static int maps__set_modules_path_dir(struct maps *maps, const char *dir_name, i struct stat st; /*sshfs might return bad dent->d_type, so we have to stat*/ - snprintf(path, sizeof(path), "%s/%s", dir_name, dent->d_name); + path__join(path, sizeof(path), dir_name, dent->d_name); if (stat(path, &st)) continue;