This patch adds NULL check for hci uart ldisc driver because some of hci uart driver allow hci_uart_tty_receive function could be called though hci uart driver is not registered properly. hci h4 driever's backtrace is attached. Backtrace: [<c05f27ec>] (hci_recv_stream_fragment+0x0/0x74) from [<c04126f4>] (h4_recv+0x18/0x40) r7:eb1d4d1c r6:eb7683b0 r5:eae8e800 r4:0000000c [<c04126dc>] (h4_recv+0x0/0x40) from [<c0411870>] (hci_uart_tty_receive+0x6c/0x94) r5:eae8e800 r4:eb768380 [<c0411804>] (hci_uart_tty_receive+0x0/0x94) from [<c027be88>] (flush_to_ldisc+0x16c/0x17c) r6:eae8e8d8 r5:eae8e800 r4:eae8e8c8 [<c027bd1c>] (flush_to_ldisc+0x0/0x17c) from [<c0050ae8>] (process_one_work+0x144/0x4d4) [<c00509a4>] (process_one_work+0x0/0x4d4) from [<c0051208>] (worker_thread+0x180/0x370) [<c0051088>] (worker_thread+0x0/0x370) from [<c005617c>] (kthread+0x90/0x9c) [<c00560ec>] (kthread+0x0/0x9c) from [<c003a3a0>] (do_exit+0x0/0x7ec) Signed-off-by: Chan-yeol Park <chanyeol.park@xxxxxxxxxxx> --- drivers/bluetooth/hci_ldisc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index ed0fade..d710d8b 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -388,7 +388,10 @@ static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *f spin_lock(&hu->rx_lock); hu->proto->recv(hu, (void *) data, count); - hu->hdev->stat.byte_rx += count; + + if (hu->hdev) + hu->hdev->stat.byte_rx += count; + spin_unlock(&hu->rx_lock); tty_unthrottle(tty); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
