Re: kernel BUG at mm/memory.c:LINE!

[Kirill A. Shutemov]

On Sun, Jul 08, 2018 at 10:51:03PM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    b2d44d145d2a Merge tag '4.18-rc3-smb3fixes' of git://git.s..
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=11d07748400000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=2ca6c7a31d407f86
> dashboard link: https://syzkaller.appspot.com/bug?extid=3f84280d52be9b7083cc
> compiler:       gcc (GCC) 8.0.1 20180413 (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+3f84280d52be9b7083cc@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> next ffff8801ce5e7040 prev ffff8801d20eca50 mm ffff88019c1e13c0
> prot 27 anon_vma ffff88019680cdd8 vm_ops 0000000000000000
> pgoff 0 file ffff8801b2ec2d00 private_data 0000000000000000
> flags: 0xff(read|write|exec|shared|mayread|maywrite|mayexec|mayshare)
> ------------[ cut here ]------------
> kernel BUG at mm/memory.c:1422!

Looks like vma_is_anonymous() false-positive.

Any clues what file is it? I would guess some kind of socket, but it's not
clear from log which exactly.

-- 
 Kirill A. Shutemov