Re: [PATCH] Bluetooth: btwilink: Save the packet type before sending

From: Marcel Holtmann
Date: Thu Sep 22 2016 - 15:48:53 EST


Hi Laura,

> Running with KASAN produces some messages:
>
> BUG: KASAN: use-after-free in ti_st_send_frame+0x9c/0x16c at addr
> ffffffc064868fe8
> Read of size 1 by task kworker/u17:1/1266
>
> <KASAN output trimmed>
>
> Hardware name: HiKey Development Board (DT)
> Workqueue: hci0 hci_cmd_work
> Call trace:
> [<ffffffc00008c00c>] dump_backtrace+0x0/0x178
> [<ffffffc00008c1a4>] show_stack+0x20/0x28
> [<ffffffc00067da38>] dump_stack+0xa8/0xe0
> [<ffffffc000288430>] print_trailer+0x110/0x174
> [<ffffffc00028aedc>] object_err+0x4c/0x5c
> [<ffffffc00028f714>] kasan_report_error+0x254/0x54c
> [<ffffffc00028fa70>] kasan_report+0x64/0x70
> [<ffffffc00028eb8c>] __asan_load1+0x4c/0x54
> [<ffffffc000b59b24>] ti_st_send_frame+0x9c/0x16c
> [<ffffffc000ee8dcc>] hci_send_frame+0xb4/0x118
> [<ffffffc000ee8efc>] hci_cmd_work+0xcc/0x154
> [<ffffffc0000f6c48>] process_one_work+0x26c/0x7a4
> [<ffffffc0000f721c>] worker_thread+0x9c/0x73c
> [<ffffffc000100250>] kthread+0x138/0x154
> [<ffffffc000085c50>] ret_from_fork+0x10/0x40
>
> The packet is being accessed for statistics after it has been freed.
> Save the packet type before sending for statistics afterwards.
>
> Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx>
> ---
> Originally found and tested on 4.4 based branch.
> ---
> drivers/bluetooth/btwilink.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel