diff options
author | Ronald Tschalär <ronald@innovation.ch> | 2017-10-25 22:15:19 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-12-20 10:10:29 +0100 |
commit | e508e6026b198b9879e0d1850fdef8ef1d4d0805 (patch) | |
tree | c0f8fb6c5080736e3f42b2a699f8f31fcd2b81d0 /drivers/bluetooth | |
parent | 7d1beb462e18b55fa5d0990d0f60fbf4edfda61b (diff) |
Bluetooth: hci_ldisc: Fix another race when closing the tty.
[ Upstream commit 0338b1b393ec7910898e8f7b25b3bf31a7282e16 ]
The following race condition still existed:
P1 P2
cancel_work_sync()
hci_uart_tx_wakeup()
hci_uart_write_work()
hci_uart_dequeue()
clear_bit(HCI_UART_PROTO_READY)
hci_unregister_dev(hdev)
hci_free_dev(hdev)
hu->proto->close(hu)
kfree(hu)
access to hdev and hu
Cancelling the work after clearing the HCI_UART_PROTO_READY bit avoids
this as any hci_uart_tx_wakeup() issued after the flag is cleared will
detect that and not schedule further work.
Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/bluetooth')
-rw-r--r-- | drivers/bluetooth/hci_ldisc.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index a746627e784e..6e2403805784 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -510,13 +510,13 @@ static void hci_uart_tty_close(struct tty_struct *tty) if (hdev) hci_uart_close(hdev); - cancel_work_sync(&hu->write_work); - if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) { write_lock_irqsave(&hu->proto_lock, flags); clear_bit(HCI_UART_PROTO_READY, &hu->flags); write_unlock_irqrestore(&hu->proto_lock, flags); + cancel_work_sync(&hu->write_work); + if (hdev) { if (test_bit(HCI_UART_REGISTERED, &hu->flags)) hci_unregister_dev(hdev); |