Re: [PATCH] Bluetooth: fix kernel null pointer dereference error on suspend

From: Marcel Holtmann
Date: Mon Jun 29 2020 - 17:14:22 EST


Hi Vamshi,

> BUG Call Trace:
> queue_work_on+0x39/0x40
> hci_adv_monitors_clear+0x71/0x90 [bluetooth]
> hci_unregister_dev+0x18a/0x2f0 [bluetooth]
> btusb_disconnect+0x68/0x150 [btusb]
> usb_unbind_interface+0x7f/0x260
> device_release_driver_internal+0xec/0x1b0
> device_release_driver+0x12/0x20
> bus_remove_device+0xe1/0x150
> device_del+0x17d/0x3e0
> usb_disable_device+0x9f/0x250
> usb_disconnect+0xc6/0x270
> hub_event+0x6da/0x18d0
> process_one_work+0x20c/0x400
> worker_thread+0x34/0x400
>
> RIP: 0010:__queue_work+0x92/0x3f0
>
> NULL deference occurs in hci_update_background_scan() while it tries
> to queue_work on already destroyed workqueues.
>
> Change hci_unregister_dev() to invoke destroy_workqueues after the
> call to hci_adv_monitors_clear().
>
> Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@xxxxxxxxx>
> ---
> net/bluetooth/hci_core.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel