Re: BUG: bad usercopy in hidraw_ioctl

[Andrey Konovalov]

On Wed, Aug 7, 2019 at 9:28 PM syzbot
<syzbot+3de312463756f656b47d@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    e96407b4 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=151b2926600000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=cfa2c18fb6a8068e
> dashboard link: https://syzkaller.appspot.com/bug?extid=3de312463756f656b47d
> 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+3de312463756f656b47d@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> usercopy: Kernel memory exposure attempt detected from wrapped address
> (offset 0, size 0)!
> ------------[ cut here ]------------
> kernel BUG at mm/usercopy.c:98!
> invalid opcode: 0000 [#1] SMP KASAN
> CPU: 1 PID: 2968 Comm: syz-executor.1 Not tainted 5.3.0-rc2+ #25
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> RIP: 0010:usercopy_abort+0xb9/0xbb mm/usercopy.c:98
> Code: e8 c1 f7 d6 ff 49 89 d9 4d 89 e8 4c 89 e1 41 56 48 89 ee 48 c7 c7 e0
> f3 cd 85 ff 74 24 08 41 57 48 8b 54 24 20 e8 15 98 c1 ff <0f> 0b e8 95 f7
> d6 ff e8 80 9f fd ff 8b 54 24 04 49 89 d8 4c 89 e1
> RSP: 0018:ffff8881b0f37be8 EFLAGS: 00010282
> RAX: 000000000000005a RBX: ffffffff85cdf100 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff8128a0fd RDI: ffffed10361e6f6f
> RBP: ffffffff85cdf2c0 R08: 000000000000005a R09: ffffed103b665d58
> R10: ffffed103b665d57 R11: ffff8881db32eabf R12: ffffffff85cdf460
> R13: ffffffff85cdf100 R14: 0000000000000000 R15: ffffffff85cdf100
> FS:  00007f539a2a9700(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000021237d0 CR3: 00000001d6ac6000 CR4: 00000000001406e0
> Call Trace:
>   check_bogus_address mm/usercopy.c:151 [inline]
>   __check_object_size mm/usercopy.c:260 [inline]
>   __check_object_size.cold+0xb2/0xba mm/usercopy.c:250
>   check_object_size include/linux/thread_info.h:119 [inline]
>   check_copy_size include/linux/thread_info.h:150 [inline]
>   copy_to_user include/linux/uaccess.h:151 [inline]
>   hidraw_ioctl+0x38c/0xae0 drivers/hid/hidraw.c:392
>   vfs_ioctl fs/ioctl.c:46 [inline]
>   file_ioctl fs/ioctl.c:509 [inline]
>   do_vfs_ioctl+0xd2d/0x1330 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+0xb7/0x580 arch/x86/entry/common.c:296
>   entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x459829
> Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
> 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
> ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007f539a2a8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
> RDX: 0000000020000800 RSI: 0000000090044802 RDI: 0000000000000004
> RBP: 000000000075c268 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f539a2a96d4
> R13: 00000000004c21f3 R14: 00000000004d55b8 R15: 00000000ffffffff
> Modules linked in:
> ---[ end trace 24b9968555bf4653 ]---
> RIP: 0010:usercopy_abort+0xb9/0xbb mm/usercopy.c:98
> Code: e8 c1 f7 d6 ff 49 89 d9 4d 89 e8 4c 89 e1 41 56 48 89 ee 48 c7 c7 e0
> f3 cd 85 ff 74 24 08 41 57 48 8b 54 24 20 e8 15 98 c1 ff <0f> 0b e8 95 f7
> d6 ff e8 80 9f fd ff 8b 54 24 04 49 89 d8 4c 89 e1
> RSP: 0018:ffff8881b0f37be8 EFLAGS: 00010282
> RAX: 000000000000005a RBX: ffffffff85cdf100 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffffffff8128a0fd RDI: ffffed10361e6f6f
> RBP: ffffffff85cdf2c0 R08: 000000000000005a R09: ffffed103b665d58
> R10: ffffed103b665d57 R11: ffff8881db32eabf R12: ffffffff85cdf460
> R13: ffffffff85cdf100 R14: 0000000000000000 R15: ffffffff85cdf100
> FS:  00007f539a2a9700(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00000000021237d0 CR3: 00000001d6ac6000 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@xxxxxxxxxxxxxxxxx
>
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Looks like the same bug:

#syz dup: KASAN: slab-out-of-bounds Read in hidraw_ioctl