Re: BUG: unable to handle kernel paging request in au0828_usb_disconnect

[Andrey Konovalov <andreyknvl@google.com>]

On Mon, Apr 29, 2019 at 2:06 PM syzbot
<syzbot+15e91d49c4c757c3d363@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    43151d6c usb-fuzzer: main usb gadget fuzzer driver
> git tree:       https://github.com/google/kasan/tree/usb-fuzzer
> console output: https://syzkaller.appspot.com/x/log.txt?x=106c9498a00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=4183eeef650d1234
> dashboard link: https://syzkaller.appspot.com/bug?extid=15e91d49c4c757c3d363
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
>
> Unfortunately, I don't have any reproducer for this crash yet.
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+15e91d49c4c757c3d363@syzkaller.appspotmail.com
>
> usb 5-1: selecting invalid altsetting 5
> au0828: Failure setting usb interface0 to as5
> au0828: au0828_usb_probe() au0828_analog_register failed to register on V4L2
> BUG: unable to handle kernel paging request at fffffffc4508a958
> #PF error: [normal kernel read fault]
> PGD 1167e067 P4D 1167e067 PUD 0
> Oops: 0000 [#1] SMP KASAN PTI
> CPU: 1 PID: 17 Comm: kworker/1:0 Not tainted 5.1.0-rc3-319004-g43151d6 #6
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Workqueue: usb_hub_wq hub_event
> RIP: 0010:decode_cpu kernel/locking/osq_lock.c:34 [inline]
> RIP: 0010:osq_lock+0xfd/0x5a0 kernel/locking/osq_lock.c:111
> Code: 48 63 e8 48 b8 00 00 00 00 00 fc ff df 48 8d 3c ed 60 b0 39 91 48 89
> f9 48 c1 e9 03 80 3c 01 00 0f 85 2c 04 00 00 48 8d 53 08 <4c> 03 2c ed 60
> b0 39 91 48 b8 00 00 00 00 00 fc ff df 48 89 d6 48
> RSP: 0018:ffff8880a84f70e8 EFLAGS: 00010246
> RAX: dffffc0000000000 RBX: ffff8880ad12dfc0 RCX: 1fffffff88a1152b
> RDX: ffff8880ad12dfc8 RSI: 0000000000000004 RDI: fffffffc4508a958
> RBP: ffffffff9679df1f R08: 0000000000000000 R09: ffffed10122cb31e
> R10: ffffed10122cb31d R11: ffff8880916598eb R12: ffff8880ad12dfd0
> R13: 000000000002dfc0 R14: ffff8880a84db100 R15: ffff8880916598e8
> FS:  0000000000000000(0000) GS:ffff8880ad100000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: fffffffc4508a958 CR3: 00000000824b6000 CR4: 00000000001406e0
> Call Trace:
>   mutex_optimistic_spin kernel/locking/mutex.c:630 [inline]
>   __mutex_lock_common kernel/locking/mutex.c:928 [inline]
>   __mutex_lock+0x27d/0x12b0 kernel/locking/mutex.c:1072
>   au0828_usb_disconnect+0xa3/0x130 drivers/media/usb/au0828/au0828-core.c:194
>   au0828_usb_probe.cold+0x121/0x7d8
> drivers/media/usb/au0828/au0828-core.c:661
>   usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
>   really_probe+0x2da/0xb10 drivers/base/dd.c:509
>   driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
>   __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
>   bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
>   __device_attach+0x223/0x3a0 drivers/base/dd.c:844
>   bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
>   device_add+0xad2/0x16e0 drivers/base/core.c:2106
>   usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2023
>   generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
>   usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
>   really_probe+0x2da/0xb10 drivers/base/dd.c:509
>   driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
>   __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
>   bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
>   __device_attach+0x223/0x3a0 drivers/base/dd.c:844
>   bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
>   device_add+0xad2/0x16e0 drivers/base/core.c:2106
>   usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534
>   hub_port_connect drivers/usb/core/hub.c:5089 [inline]
>   hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
>   port_event drivers/usb/core/hub.c:5350 [inline]
>   hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432
>   process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
>   worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
>   kthread+0x313/0x420 kernel/kthread.c:253
>   ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
> Modules linked in:
> CR2: fffffffc4508a958
> ---[ end trace e04421c5fdf22ecf ]---
> RIP: 0010:decode_cpu kernel/locking/osq_lock.c:34 [inline]
> RIP: 0010:osq_lock+0xfd/0x5a0 kernel/locking/osq_lock.c:111
> Code: 48 63 e8 48 b8 00 00 00 00 00 fc ff df 48 8d 3c ed 60 b0 39 91 48 89
> f9 48 c1 e9 03 80 3c 01 00 0f 85 2c 04 00 00 48 8d 53 08 <4c> 03 2c ed 60
> b0 39 91 48 b8 00 00 00 00 00 fc ff df 48 89 d6 48
> RSP: 0018:ffff8880a84f70e8 EFLAGS: 00010246
> RAX: dffffc0000000000 RBX: ffff8880ad12dfc0 RCX: 1fffffff88a1152b
> RDX: ffff8880ad12dfc8 RSI: 0000000000000004 RDI: fffffffc4508a958
> RBP: ffffffff9679df1f R08: 0000000000000000 R09: ffffed10122cb31e
> R10: ffffed10122cb31d R11: ffff8880916598eb R12: ffff8880ad12dfd0
> R13: 000000000002dfc0 R14: ffff8880a84db100 R15: ffff8880916598e8
> FS:  0000000000000000(0000) GS:ffff8880ad100000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: fffffffc4508a958 CR3: 00000000824b6000 CR4: 00000000001406e0
>
>
> ---
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>
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#syz dup: KASAN: slab-out-of-bounds Read in au0828_rc_unregister (2)