Bluetooth: hci_core: Fix queuing tx_work after workqueue is drained

hci_send_acl(), hci_send_sco() and hci_send_iso() queue hdev->tx_work
unconditionally. They can run from the L2CAP/SCO/ISO socket send path
while hci_dev_close_sync() is draining hdev->workqueue (HCIDEVDOWN
racing with a socket write). Since that queue_work() is not chained
work from the tx_work worker itself, __queue_work() sees the queue
marked __WQ_DRAINING, warns "cannot queue %ps on wq %s", and drops
the work:

  WARNING: CPU: 1 PID: 5985 at kernel/workqueue.c:2352 __queue_work
  Call Trace:
   queue_work_on
   l2cap_chan_send
   l2cap_sock_sendmsg
   ...

hci_dev_close_sync() already sets HCI_CMD_DRAIN_WORKQUEUE before
draining, but only hci_cmd_work() and handle_cmd_cnt_and_timer()
check it before queuing. Route the tx_work producers through the
same guard via a shared hci_sched_tx() helper.

Fixes: 525daaea459f ("Bluetooth: hci_sync: Set HCI_CMD_DRAIN_WORKQUEUE during device close")
Reported-by: syzbot+b6919040d9958e2fc1ae@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b6919040d9958e2fc1ae
Signed-off-by: ThangNN99 <ngocthang2710.1999@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

0 files changed, 0 insertions, 0 deletions