From: Jiri Slaby <jslaby@suse.cz>
Date: Mon, 28 Feb 2011 09:34:06 +0000 (+0100)
Subject: USB: serial/kobil_sct, fix potential tty NULL dereference
X-Git-Tag: v2.6.38.1~53
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0a04fbe5bb3d98d3ee553e9fec49ac9e16cc3217;p=karo-tx-linux.git

USB: serial/kobil_sct, fix potential tty NULL dereference

commit 6960f40a954619857e7095a6179eef896f297077 upstream.

Make sure that we check the return value of tty_port_tty_get.
Sometimes it may return NULL and we later dereference that.

The only place here is in kobil_read_int_callback, so fix it.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/usb/serial/kobil_sct.c b/drivers/usb/serial/kobil_sct.c
index bd5bd8589e04..b382d9a0274d 100644
--- a/drivers/usb/serial/kobil_sct.c
+++ b/drivers/usb/serial/kobil_sct.c
@@ -372,7 +372,7 @@ static void kobil_read_int_callback(struct urb *urb)
 	}
 
 	tty = tty_port_tty_get(&port->port);
-	if (urb->actual_length) {
+	if (tty && urb->actual_length) {
 
 		/* BEGIN DEBUG */
 		/*