passt: Explicitly check return value of chdir()

...it doesn't actually matter as we're checking errno at the very
end, but, depending on build flags, chdir() might be declared with
warn_unused_result and the compiler issues a warning.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/passt.c b/passt.c
index 3d18d1f..038d50a 100644
--- a/passt.c
+++ b/passt.c
@@ -260,7 +260,9 @@ static int sandbox(struct ctx *c)
 	mount("", "/", "", MS_UNBINDABLE | MS_REC, NULL);
 	mount("", TMPDIR, "tmpfs", MS_NODEV | MS_NOEXEC | MS_NOSUID | MS_RDONLY,
 	      "nr_inodes=2,nr_blocks=0");
-	chdir(TMPDIR);
+	if (chdir(TMPDIR))
+		return -errno;
+
 	syscall(SYS_pivot_root, ".", ".");
 	umount2(".", MNT_DETACH | UMOUNT_NOFOLLOW);