From: Jiri Slaby <jslaby@suse.cz>
Date: Sun, 5 Jun 2011 12:16:17 +0000 (+0200)
Subject: TTY: ntty, add one more sanity check
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2872628680bad71a6734e7d379168f990a91cc09;p=linux-beck.git

TTY: ntty, add one more sanity check

With the previous patch, we fixed another bug where read_buf was freed
while we still was in n_tty_read. We currently check whether read_buf
is NULL at the start of the function. Add one more check after we wake
up from waiting for input.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 0ad32888091c..c3954fbf6ac4 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -1815,6 +1815,7 @@ do_it_again:
 			/* FIXME: does n_tty_set_room need locking ? */
 			n_tty_set_room(tty);
 			timeout = schedule_timeout(timeout);
+			BUG_ON(!tty->read_buf);
 			continue;
 		}
 		__set_current_state(TASK_RUNNING);