sulogin: bail out from getpasswd(...) on timeout

If timeout happens while waiting in prompt, bail out instead
of retrying.

Reported-by: Bjørn Mork <bjorn@mork.no>
Addresses: http://bugs.debian.org/846107
Signed-off-by: Andreas Henriksson <andreas@fatal.se>

login-utils/sulogin.c

@@ -645,6 +645,10 @@ static char *getpasswd(struct console *con)
 	while (cp->eol == '\0') {
 		if (read(fd, &c, 1) < 1) {
 			if (errno == EINTR || errno == EAGAIN) {
+				if (alarm_rised) {
+					ret = NULL;
+					goto quit;
+				}
 				xusleep(250000);
 				continue;
 			}