fts: don't operate on an invalid file descriptor after failed dup

* lib/fts.c (fts_build): Don't call set_cloexec_flag on a
negative file descriptor.

1 files changed, 2 insertions, 1 deletions

diff --git a/lib/fts.c b/lib/fts.c
index a308a8c94e..4b89ee780b 100644
--- a/lib/fts.c
+++ b/lib/fts.c
@@ -1305,7 +1305,8 @@ fts_build (register FTS *sp, int type)
                 if (ISSET(FTS_CWDFD) && 0 <= dir_fd)
                   {
                     dir_fd = dup (dir_fd);
-                    set_cloexec_flag (dir_fd, true);
+                    if (0 <= dir_fd)
+                      set_cloexec_flag (dir_fd, true);
                   }
                 if (dir_fd < 0 || fts_safe_changedir(sp, cur, dir_fd, NULL)) {
                         if (nlinks && type == BREAD)