cmsg: recvfd returns an error on failures

Signed-off-by: Giuseppe Scrivano <[email protected]>

src/cmsg.c

@@ -162,5 +162,5 @@ struct file_t recvfd(int sockfd)
 	olderrno = errno;
 	free(file.name);
 	errno = olderrno;
-	return (struct file_t){0};
+	return (struct file_t){.name = NULL, .fd = -1};
 }

src/ctrl.c

@@ -47,6 +47,11 @@ gboolean terminal_accept_cb(int fd, G_GNUC_UNUSED GIOCondition condition, G_GNUC
 	ndebugf("about to recvfd from connfd: %d", connfd);
 	struct file_t console = recvfd(connfd);
 
+	if (console.fd < 0) {
+		nwarn("Failed to receive console file descriptor");
+		goto exit;
+	}
+
 	ndebugf("console = {.name = '%s'; .fd = %d}", console.name, console.fd);
 	free(console.name);
 

src/seccomp_notify.c

@@ -76,6 +76,11 @@ gboolean seccomp_accept_cb(int fd, G_GNUC_UNUSED GIOCondition condition, G_GNUC_
 	struct file_t listener = recvfd(connfd);
 	close(connfd);
 
+	if (listener.fd < 0) {
+		nwarn("Failed to receive socket listener file descriptor");
+		return G_SOURCE_CONTINUE;
+	}
+
 	_cleanup_free_ char *oci_config_path = g_strdup_printf("%s/config.json", opt_bundle_path);
 	if (oci_config_path == NULL) {
 		nwarn("Failed to allocate memory");