From 018c778689c84a905e274548c1e37b3cbd2704e3 Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Fri, 22 Oct 2010 14:11:26 +0100
Subject: [PATCH] --- yaml --- r: 212906 b: refs/heads/master c:
 c19483cc5e56ac5e22dd19cf25ba210ab1537773 h: refs/heads/master v: v3

---
 [refs]                              | 2 +-
 trunk/drivers/bluetooth/hci_ldisc.c | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 5df2d2218367..726fb19d73f3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d4429f608abde89e8bc1e24b43cd503feb95c496
+refs/heads/master: c19483cc5e56ac5e22dd19cf25ba210ab1537773
diff --git a/trunk/drivers/bluetooth/hci_ldisc.c b/trunk/drivers/bluetooth/hci_ldisc.c
index 998833d93c13..17361bad46dd 100644
--- a/trunk/drivers/bluetooth/hci_ldisc.c
+++ b/trunk/drivers/bluetooth/hci_ldisc.c
@@ -256,9 +256,16 @@ static int hci_uart_tty_open(struct tty_struct *tty)
 
 	BT_DBG("tty %p", tty);
 
+	/* FIXME: This btw is bogus, nothing requires the old ldisc to clear
+	   the pointer */
 	if (hu)
 		return -EEXIST;
 
+	/* Error if the tty has no write op instead of leaving an exploitable
+	   hole */
+	if (tty->ops->write == NULL)
+		return -EOPNOTSUPP;
+
 	if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
 		BT_ERR("Can't allocate control structure");
 		return -ENFILE;