[alsa-devel] usb/sound/line6: trying to register non-static key in podhd_disconnect

[Takashi Iwai]

On Mon, 09 Oct 2017 16:11:00 +0200,
Andrey Konovalov wrote:
> 
> On Mon, Oct 9, 2017 at 2:59 PM, Takashi Iwai <tiwai at suse.de> wrote:
> > On Mon, 09 Oct 2017 14:39:44 +0200,
> > Andrey Konovalov wrote:
> >>
> >> On Mon, Oct 9, 2017 at 2:31 PM, Takashi Iwai <tiwai at suse.de> wrote:
> >> > On Mon, 09 Oct 2017 12:58:59 +0200,
> >> > Andrey Konovalov wrote:
> >> >>
> >> >> On Tue, Oct 3, 2017 at 9:41 AM, Takashi Iwai <tiwai at suse.de> wrote:
> >> >> > On Mon, 25 Sep 2017 14:40:08 +0200,
> >> >> > Andrey Konovalov wrote:
> >> >> >>
> >> >> >> Hi!
> >> >> >>
> >> >> >> I've got the following report while fuzzing the kernel with syzkaller.
> >> >> >>
> >> >> >> On commit e19b205be43d11bff638cad4487008c48d21c103 (4.14-rc2).
> >> >> >>
> >> >> >> INFO: trying to register non-static key.
> >> >> >> the code is fine but needs lockdep annotation.
> >> >> >> turning off the locking correctness validator.
> >> >> >> CPU: 1 PID: 1845 Comm: kworker/1:2 Not tainted
> >> >> >> 4.14.0-rc2-42613-g1488251d1a98 #238
> >> >> >> 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
> >> >> >>  del_timer_sync+0x12c/0x280 kernel/time/timer.c:1237
> >> >> >>  podhd_disconnect+0x8c/0x160 sound/usb/line6/podhd.c:299
> >> >> >>  line6_probe+0x844/0x1310 sound/usb/line6/driver.c:783
> >> >> >>  podhd_probe+0x64/0x70 sound/usb/line6/podhd.c:474
> >> >> >>  usb_probe_interface+0x35d/0x8e0 drivers/usb/core/driver.c:361
> >> >> >>  really_probe drivers/base/dd.c:413
> >> >> >>  driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
> >> >> >>  __device_attach_driver+0x230/0x290 drivers/base/dd.c:653
> >> >> >>  bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
> >> >> >>  __device_attach+0x26e/0x3d0 drivers/base/dd.c:710
> >> >> >>  device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
> >> >> >>  bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
> >> >> >>  device_add+0xd0b/0x1660 drivers/base/core.c:1835
> >> >> >>  usb_set_configuration+0x104e/0x1870 drivers/usb/core/message.c:1932
> >> >> >>  generic_probe+0x73/0xe0 drivers/usb/core/generic.c:174
> >> >> >>  usb_probe_device+0xaf/0xe0 drivers/usb/core/driver.c:266
> >> >> >>  really_probe drivers/base/dd.c:413
> >> >> >>  driver_probe_device+0x610/0xa00 drivers/base/dd.c:557
> >> >> >>  __device_attach_driver+0x230/0x290 drivers/base/dd.c:653
> >> >> >>  bus_for_each_drv+0x161/0x210 drivers/base/bus.c:463
> >> >> >>  __device_attach+0x26e/0x3d0 drivers/base/dd.c:710
> >> >> >>  device_initial_probe+0x1f/0x30 drivers/base/dd.c:757
> >> >> >>  bus_probe_device+0x1eb/0x290 drivers/base/bus.c:523
> >> >> >>  device_add+0xd0b/0x1660 drivers/base/core.c:1835
> >> >> >>  usb_new_device+0x7b8/0x1020 drivers/usb/core/hub.c:2457
> >> >> >>  hub_port_connect drivers/usb/core/hub.c:4903
> >> >> >>  hub_port_connect_change drivers/usb/core/hub.c:5009
> >> >> >>  port_event drivers/usb/core/hub.c:5115
> >> >> >>  hub_event+0x194d/0x3740 drivers/usb/core/hub.c:5195
> >> >> >>  process_one_work+0xc7f/0x1db0 kernel/workqueue.c:2119
> >> >> >>  worker_thread+0x221/0x1850 kernel/workqueue.c:2253
> >> >> >>  kthread+0x3a1/0x470 kernel/kthread.c:231
> >> >> >>  ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431
> >> >> >
> >> >> > This looks like an access to the uninitialized timer object.
> >> >> > Could you check the patch below whether it fixes the issue?
> >> >> > Thanks!
> >> >> >
> >> >> >
> >> >> > Takashi
> >> >>
> >> >> Hi Takashi,
> >> >>
> >> >> I've applied your patch and now get GPF on
> >> >> usb_driver_release_interface(&podhd_driver, intf):
> >> >
> >> > Another day, another Oops...  The patch below should cover it.
> >> > I'm going to queue both now.
> >>
> >> With these two patches I get:
> >>
> >> kasan: CONFIG_KASAN_INLINE enabled
> >> kasan: GPF could be caused by NULL-ptr deref or user memory access
> >> general protection fault: 0000 [#1] PREEMPT SMP KASAN
> >> Modules linked in:
> >> CPU: 1 PID: 0 Comm: swapper/1 Not tainted
> >> 4.14.0-rc4-43414-g3c9155515146-dirty #372
> >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
> >> task: ffff88006baa3180 task.stack: ffff88006bac0000
> >> RIP: 0010:usb_fill_bulk_urb ./include/linux/usb.h:1619
> >> RIP: 0010:line6_start_listen+0x3fe/0x9e0 sound/usb/line6/driver.c:76
> >
> > Sight, is tonight a full-moon?
> > This is another bug, an overlook in the error handling.
> > The fix patch is below.
> 
> The 3 patches together fix the crash with my reproducer =)
> 
> Thanks a lot!
> 
> Tested-by: Andrey Konovalov <andreyknvl at google.com>

OK, all three patches are queued now to for-linus branch.
Thanks for a quick testing.


Takashi