Subject: Re: [v2] p54: don't unregister leds when they are not initialized

From: Kalle Valo <[email-masked]>
Date: Tue, 10 Oct 2017 08:18:59 +0000 (UTC)

Andrey Konovalov <[email-masked]> wrote:

> ieee80211_register_hw() in p54_register_common() may fail and leds won't
> get initialized. Currently p54_unregister_common() doesn't check that and
> always calls p54_unregister_leds(). The fix is to check priv->registered
> flag before calling p54_unregister_leds().
> 
> Found by syzkaller.
> 
> INFO: trying to register non-static key.
> the code is fine but needs lockdep annotation.
> turning off the locking correctness validator.
> CPU: 1 PID: 1404 Comm: kworker/1:1 Not tainted
> 4.14.0-rc1-42251-gebb2c2437d80-dirty #205
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> Workqueue: usb_hub_wq hub_event
> Call Trace:
>  __dump_stack lib/dump_stack.c:16
>  dump_stack+0x292/0x395 lib/dump_stack.c:52
>  register_lock_class+0x6c4/0x1a00 kernel/locking/lockdep.c:769
>  __lock_acquire+0x27e/0x4550 kernel/locking/lockdep.c:3385
>  lock_acquire+0x259/0x620 kernel/locking/lockdep.c:4002
>  flush_work+0xf0/0x8c0 kernel/workqueue.c:2886
>  __cancel_work_timer+0x51d/0x870 kernel/workqueue.c:2961
>  cancel_delayed_work_sync+0x1f/0x30 kernel/workqueue.c:3081
>  p54_unregister_leds+0x6c/0xc0 drivers/net/wireless/intersil/p54/led.c:160
>  p54_unregister_common+0x3d/0xb0 drivers/net/wireless/intersil/p54/main.c:856
>  p54u_disconnect+0x86/0x120 drivers/net/wireless/intersil/p54/p54usb.c:1073
>  usb_unbind_interface+0x21c/0xa90 drivers/usb/core/driver.c:423
>  __device_release_driver drivers/base/dd.c:861
>  device_release_driver_internal+0x4f4/0x5c0 drivers/base/dd.c:893
>  device_release_driver+0x1e/0x30 drivers/base/dd.c:918
>  bus_remove_device+0x2f4/0x4b0 drivers/base/bus.c:565
>  device_del+0x5c4/0xab0 drivers/base/core.c:1985
>  usb_disable_device+0x1e9/0x680 drivers/usb/core/message.c:1170
>  usb_disconnect+0x260/0x7a0 drivers/usb/core/hub.c:2124
>  hub_port_connect drivers/usb/core/hub.c:4754
>  hub_port_connect_change drivers/usb/core/hub.c:5009
>  port_event drivers/usb/core/hub.c:5115
>  hub_event+0x1318/0x3740 drivers/usb/core/hub.c:5195
>  process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119
>  process_scheduled_works kernel/workqueue.c:2179
>  worker_thread+0xb2b/0x1850 kernel/workqueue.c:2255
>  kthread+0x3a1/0x470 kernel/kthread.c:231
>  ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
> 
> Cc: [email-masked]
> Signed-off-by: Andrey Konovalov <[email-masked]>
> Acked-by: Christian Lamparter <[email-masked]>

Patch applied to wireless-drivers-next.git, thanks.

fc09785de0a3 p54: don't unregister leds when they are not initialized

-- 
https://patchwork.kernel.org/patch/9972281/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches