Re: general protection fault in vidioc_querycap

Andrey Konovalov
2020-06-18T12:04:43Z

On Tue, Jul 9, 2019 at 2:27 PM syzbot
<syzbot+646272341e25afebff05@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: 7829a896 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=1321f9a3a00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=f6d4561982f71f63
> dashboard link: https://syzkaller.appspot.com/bug?extid=646272341e25afebff05
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12ac261ba00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=171d6739a00000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+646272341e25afebff05@syzkaller.appspotmail.com
>
> kasan: CONFIG_KASAN_INLINE enabled
> kasan: GPF could be caused by NULL-ptr deref or user memory access
> general protection fault: 0000 [#1] SMP KASAN
> CPU: 1 PID: 1878 Comm: v4l_id Not tainted 5.2.0-rc6+ #13
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> RIP: 0010:usb_make_path include/linux/usb.h:913 [inline]
> RIP: 0010:vidioc_querycap+0x12d/0x3e0
> drivers/media/usb/usbvision/usbvision-video.c:461
> Code: 3c 02 00 0f 85 ba 02 00 00 49 8b ac 24 58 16 00 00 48 b8 00 00 00 00
> 00 fc ff df 48 8d 7d 48 4c 8d 45 04 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f
> 85 7d 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b
> RSP: 0018:ffff8881cc727a28 EFLAGS: 00010206
> RAX: dffffc0000000000 RBX: ffff8881cc727c20 RCX: 0000000000000000
> RDX: 0000000000000009 RSI: 451f481f4b404f27 RDI: 0000000000000048
> RBP: 0000000000000000 R08: 0000000000000004 R09: fffffbfff0c9ba38
> R10: fffffbfff0c9ba37 R11: ffffffff864dd1b8 R12: ffff8881cc9aa100
> R13: ffff8881cc9ab804 R14: ffff8881cc9aa998 R15: ffff8881cc727c50
> FS: 00007f579210f700(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000625208 CR3: 00000001cd192000 CR4: 00000000001406e0
> Call Trace:
> v4l_querycap+0x121/0x340 drivers/media/v4l2-core/v4l2-ioctl.c:1058
> __video_do_ioctl+0x5b0/0xb30 drivers/media/v4l2-core/v4l2-ioctl.c:2871
> video_usercopy+0x446/0xee0 drivers/media/v4l2-core/v4l2-ioctl.c:3053
> v4l2_ioctl+0x147/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:360
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:696
> ksys_ioctl+0x9b/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:718
> do_syscall_64+0xb7/0x560 arch/x86/entry/common.c:301
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x7f5791c42347
> Code: 90 90 90 48 8b 05 f1 fa 2a 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff
> ff c3 90 90 90 90 90 90 90 90 90 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff
> ff 73 01 c3 48 8b 0d c1 fa 2a 00 31 d2 48 29 c2 64
> RSP: 002b:00007ffced1878d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f5791c42347
> RDX: 00007ffced1878e0 RSI: 0000000080685600 RDI: 0000000000000003
> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000400884
> R13: 00007ffced187a30 R14: 0000000000000000 R15: 0000000000000000
> Modules linked in:
> ---[ end trace 5550531bc37b28bc ]---
> RIP: 0010:usb_make_path include/linux/usb.h:913 [inline]
> RIP: 0010:vidioc_querycap+0x12d/0x3e0
> drivers/media/usb/usbvision/usbvision-video.c:461
> Code: 3c 02 00 0f 85 ba 02 00 00 49 8b ac 24 58 16 00 00 48 b8 00 00 00 00
> 00 fc ff df 48 8d 7d 48 4c 8d 45 04 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f
> 85 7d 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b
> RSP: 0018:ffff8881cc727a28 EFLAGS: 00010206
> RAX: dffffc0000000000 RBX: ffff8881cc727c20 RCX: 0000000000000000
> RDX: 0000000000000009 RSI: 451f481f4b404f27 RDI: 0000000000000048
> RBP: 0000000000000000 R08: 0000000000000004 R09: fffffbfff0c9ba38
> R10: fffffbfff0c9ba37 R11: ffffffff864dd1b8 R12: ffff8881cc9aa100
> R13: ffff8881cc9ab804 R14: ffff8881cc9aa998 R15: ffff8881cc727c50
> FS: 00007f579210f700(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000625208 CR3: 00000001cd192000 CR4: 00000000001406e0
>
>
> ---
> 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.
>
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> syzbot can test patches for this bug, for details see:
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Closing old USB bugs that haven't happened for a long time.

#syz invalid