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From:   Andrey Konovalov <andreyknvl@google.com>
Date:   Mon, 9 Mar 2020 16:24:00 +0100
Message-ID: <CAAeHK+zzdt2ua0XX2_rzuW=+Vs7SQvKgLMz5wir=xh0cqnFTuw@mail.gmail.com>
Subject: Re: WARNING in em28xx_init_extension
To:     syzbot <syzbot+76929be61691e7b3904b@syzkaller.appspotmail.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, linux-media@vger.kernel.org,
        USB list <linux-usb@vger.kernel.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>
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Sender: linux-kernel-owner@vger.kernel.org
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On Fri, Sep 27, 2019 at 10:49 PM syzbot
<syzbot+76929be61691e7b3904b@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    2994c077 usb-fuzzer: main usb gadget fuzzer driver
> git tree:       https://github.com/google/kasan.git usb-fuzzer
> console output: https://syzkaller.appspot.com/x/log.txt?x=171c4be3600000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=69ddefac6929256a
> dashboard link: https://syzkaller.appspot.com/bug?extid=76929be61691e7b3904b
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=137d73bd600000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14f0c8cb600000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+76929be61691e7b3904b@syzkaller.appspotmail.com
>
> em28xx 1-1:0.221: Audio interface 221 found (Vendor Class)
> em28xx 1-1:0.221: unknown em28xx chip ID (0)
> em28xx 1-1:0.221: Config register raw data: 0xfffffffb
> em28xx 1-1:0.221: AC97 chip type couldn't be determined
> em28xx 1-1:0.221: No AC97 audio processor
> ------------[ cut here ]------------
> list_add corruption. prev->next should be next (ffffffff87779de0), but was
> ffffffff8352fdcc. (prev=ffff8881d2ecc240).
> WARNING: CPU: 1 PID: 83 at lib/list_debug.c:26 __list_add_valid+0x99/0xf0
> lib/list_debug.c:26
> Kernel panic - not syncing: panic_on_warn set ...
> CPU: 1 PID: 83 Comm: kworker/1:2 Not tainted 5.3.0+ #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Workqueue: usb_hub_wq hub_event
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0xca/0x13e lib/dump_stack.c:113
>   panic+0x2a3/0x6da kernel/panic.c:219
>   __warn.cold+0x20/0x4a kernel/panic.c:576
>   report_bug+0x262/0x2a0 lib/bug.c:186
>   fixup_bug arch/x86/kernel/traps.c:179 [inline]
>   fixup_bug arch/x86/kernel/traps.c:174 [inline]
>   do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272
>   do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291
>   invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
> RIP: 0010:__list_add_valid+0x99/0xf0 lib/list_debug.c:26
> Code: 48 c7 c7 60 06 db 85 e8 2a 7a 30 ff 0f 0b 48 83 c4 08 31 c0 5d 41 5c
> c3 48 89 f1 48 c7 c7 20 07 db 85 4c 89 e6 e8 0c 7a 30 ff <0f> 0b 31 c0 eb
> c5 48 89 f2 4c 89 e1 48 89 ee 48 c7 c7 a0 07 db 85
> RSP: 0018:ffff8881d93cf120 EFLAGS: 00010286
> RAX: 0000000000000000 RBX: ffff8881d2810120 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff8128d3fd RDI: ffffed103b279e16
> RBP: ffff8881d2810240 R08: ffff8881d92a3000 R09: fffffbfff11f45af
> R10: fffffbfff11f45ae R11: ffffffff88fa2d77 R12: ffffffff87779de0
> R13: ffff8881d2810000 R14: ffff8881d281012c R15: ffff8881d2c84400
>   __list_add include/linux/list.h:60 [inline]
>   list_add_tail include/linux/list.h:93 [inline]
>   em28xx_init_extension+0x44/0x1f0
> drivers/media/usb/em28xx/em28xx-core.c:1125
>   em28xx_init_dev.isra.0+0xa7b/0x15d8
> drivers/media/usb/em28xx/em28xx-cards.c:3520
>   em28xx_usb_probe.cold+0xcac/0x2516
> drivers/media/usb/em28xx/em28xx-cards.c:3869
>   usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
>   really_probe+0x281/0x6d0 drivers/base/dd.c:548
>   driver_probe_device+0x104/0x210 drivers/base/dd.c:721
>   __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
>   bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
>   __device_attach+0x217/0x360 drivers/base/dd.c:894
>   bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
>   device_add+0xae6/0x16f0 drivers/base/core.c:2201
>   usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
>   generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
>   usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
>   really_probe+0x281/0x6d0 drivers/base/dd.c:548
>   driver_probe_device+0x104/0x210 drivers/base/dd.c:721
>   __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
>   bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
>   __device_attach+0x217/0x360 drivers/base/dd.c:894
>   bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
>   device_add+0xae6/0x16f0 drivers/base/core.c:2201
>   usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536
>   hub_port_connect drivers/usb/core/hub.c:5098 [inline]
>   hub_port_connect_change drivers/usb/core/hub.c:5213 [inline]
>   port_event drivers/usb/core/hub.c:5359 [inline]
>   hub_event+0x1b5c/0x3640 drivers/usb/core/hub.c:5441
>   process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
>   process_scheduled_works kernel/workqueue.c:2331 [inline]
>   worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
>   kthread+0x318/0x420 kernel/kthread.c:255
>   ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
> Kernel Offset: disabled
> Rebooting in 86400 seconds..
>
>
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this bug report. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> syzbot can test patches for this bug, for details see:
> https://goo.gl/tpsmEJ#testing-patches

#syz dup: BUG: corrupted list in em28xx_init_extension