From c19483cc5e56ac5e22dd19cf25ba210ab1537773 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 22 Oct 2010 14:11:26 +0100 Subject: [PATCH] bluetooth: Fix missing NULL check Fortunately this is only exploitable on very unusual hardware. [Reported a while ago but nothing happened so just fixing it] Signed-off-by: Alan Cox Cc: stable@kernel.org Signed-off-by: Linus Torvalds --- drivers/bluetooth/hci_ldisc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index 998833d93c13..17361bad46dd 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/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; -- 2.30.2