[ Upstream commit 258c81b341c8025d79073ce2d6ce19dcdc7d10d2 ] In vhci_device_unlink_cleanup(), the URBs for unsent unlink requests are not given back. This sometimes causes usb_kill_urb to wait indefinitely for that urb to be given back. syzbot has reported a hung task issue [1] for this. To fix this, give back the urbs corresponding to unsent unlink requests (unlink_tx list) similar to how urbs corresponding to unanswered unlink requests (unlink_rx list) are given back. [1]: https://syzkaller.appspot.com/bug?id=08f12df95ae7da69814e64eb5515d5a85ed06b76 Reported-by: syzbot+74d6ef051d3d2eacf428@syzkaller.appspotmail.com Tested-by: syzbot+74d6ef051d3d2eacf428@syzkaller.appspotmail.com Reviewed-by: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com> Link: https://lore.kernel.org/r/20210820190122.16379-2-mail@anirudhrb.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
TODO: - more discussion about the protocol - testing - review of the userspace interface - document the protocol Please send patches for this code to Greg Kroah-Hartman <greg@kroah.com>