Let's add an extra safety check before we chmod/chown a TTY to the right user,
as we might end up having connected something to STDIN/STDOUT that is actually
not a TTY, even though this might have been requested, due to permissive
StandardInput= settings or transient service activation with fds passed in.
Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=85255
assert(fd >= 0);
+ /* Before we chown/chmod the TTY, let's ensure this is actually a tty */
+ if (isatty(fd) < 1)
+ return 0;
+
/* This might fail. What matters are the results. */
(void) fchown(fd, uid, -1);
(void) fchmod(fd, TTY_MODE);