Re: KASAN: user-memory-access Read in hidraw_ioctl

[Andrey Konovalov]

On Tue, Jul 30, 2019 at 2:28 PM syzbot
<syzbot+5a8c44432a51154ff6d5@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    7f7867ff 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=13c21ab4600000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=792eb47789f57810
> dashboard link: https://syzkaller.appspot.com/bug?extid=5a8c44432a51154ff6d5
> 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+5a8c44432a51154ff6d5@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> ==================================================================
> BUG: KASAN: user-memory-access in _copy_to_user+0x124/0x150
> lib/usercopy.c:27
> Read of size 148 at addr 0000100000000000 by task syz-executor.2/19576
>
> CPU: 1 PID: 19576 Comm: syz-executor.2 Not tainted 5.3.0-rc2+ #23
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0xca/0x13e lib/dump_stack.c:113
>   __kasan_report.cold+0x5/0x33 mm/kasan/report.c:486
>   kasan_report+0xe/0x12 mm/kasan/common.c:612
>   check_memory_region_inline mm/kasan/generic.c:185 [inline]
>   check_memory_region+0x128/0x190 mm/kasan/generic.c:192
>   _copy_to_user+0x124/0x150 lib/usercopy.c:27
>   copy_to_user include/linux/uaccess.h:152 [inline]
>   hidraw_ioctl+0x39c/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:00007f6587cfbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459829
> RDX: 0000000020005640 RSI: 0000000090044802 RDI: 0000000000000004
> RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6587cfc6d4
> R13: 00000000004c21db R14: 00000000004d5540 R15: 00000000ffffffff
> ==================================================================

#syz dup: BUG: bad usercopy in hidraw_ioctl

>
>
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