Re: BUG: divide error in ubi_attach_mtd_dev

[Yu Hao]

Sorry that there is a mistake for the full report.
It should be https://gist.github.com/ZHYfeng/ae66bf8167bc341d3753af00e9902b1a

On Mon, Apr 17, 2023 at 10:10 PM Yu Hao <yhao016@xxxxxxx> wrote:
>
> Hello,
>
> We found the following issue using syzkaller on Linux v6.2.0.
> The full report:
> https://gist.github.com/ZHYfeng/a3e3ff2bdfea5ed5de5475f0b54d55cb
>
> The brief report is below:
>
> ubi: mtd0 is already attached to ubi0
> ubi7: attaching mtd147
> divide error: 0000 [#1] PREEMPT SMP KASAN
> CPU: 0 PID: 20023 Comm: syz-executor.0 Not tainted 6.2.0 #6
> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.13.0-1ubuntu1.1 04/01/2014
> RIP: 0010:mtd_div_by_eb include/linux/mtd/mtd.h:580 [inline]
> RIP: 0010:io_init drivers/mtd/ubi/build.c:620 [inline]
> RIP: 0010:ubi_attach_mtd_dev+0x77f/0x2fe0 drivers/mtd/ubi/build.c:955
> Code: fc ff df 48 c1 ea 03 0f b6 14 02 4c 89 f0 83 e0 07 83 c0 03 38
> d0 7c 08 84 d2 0f 85 1f 25 00 00 41 8b 4c 24 10 48 89 d8 31 d2 <48> f7
> f1 48 89 c3 e8 b6 f3 1b fc 48 8d 85 40 17 00 00 48 89 c2 48
> RSP: 0018:ffffc9000be0fd30 EFLAGS: 00010246
> RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
> RDX: 0000000000000000 RSI: ffff888047a49d40 RDI: 0000000000000002
> RBP: ffff888024e1c000 R08: 0000000000000016 R09: fffff520017c1f47
> R10: ffffc9000be0fa37 R11: fffff520017c1f46 R12: ffff88806545a000
> R13: 0000000000000000 R14: ffff88806545a010 R15: 0000000000000007
> FS:  00007fd45e85c700(0000) GS:ffff88802ca00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f64aeef53a4 CR3: 000000004f39a000 CR4: 0000000000350ef0
> Call Trace:
>  <TASK>
>  ctrl_cdev_ioctl+0x303/0x3a0 drivers/mtd/ubi/cdev.c:1043
>  vfs_ioctl fs/ioctl.c:51 [inline]
>  __do_sys_ioctl fs/ioctl.c:870 [inline]
>  __se_sys_ioctl fs/ioctl.c:856 [inline]
>  __x64_sys_ioctl+0x198/0x210 fs/ioctl.c:856
>  do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>  do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
>  entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x7fd45d6902fd
> Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007fd45e85bc58 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 00007fd45d7bbf60 RCX: 00007fd45d6902fd
> RDX: 0000000020000000 RSI: 0000000040186f40 RDI: 0000000000000005
> RBP: 00007fd45d6fec89 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007fff676814bf R14: 00007fff67681670 R15: 00007fd45e85bdc0
>  </TASK>