Re: BUG: unable to handle kernel paging request in check_memory_region

From: Eric Biggers
Date: Tue Jan 30 2018 - 20:41:45 EST


On Sun, Jan 14, 2018 at 01:22:13AM +0100, Daniel Borkmann wrote:
> On 01/13/2018 08:29 AM, Dmitry Vyukov wrote:
> > On Fri, Jan 12, 2018 at 11:58 PM, syzbot
> > <syzbot+32b24f3e7c9000c48490@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> >> Hello,
> >>
> >> syzkaller hit the following crash on
> >> c92a9a461dff6140c539c61e457aa97df29517d6
> >> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> >> compiler: gcc (GCC) 7.1.1 20170620
> >> .config is attached
> >> Raw console output is attached.
> >> C reproducer is attached
> >> syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> >> for information about syzkaller reproducers
> >>
> >>
> >> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> >> Reported-by: syzbot+32b24f3e7c9000c48490@xxxxxxxxxxxxxxxxxxxxxxxxx
> >> It will help syzbot understand when the bug is fixed. See footer for
> >> details.
> >> If you forward the report, please keep this part and the footer.
> >
> >
> > Daniel, is it the same bug that was fixed by "bpf, array: fix overflow
> > in max_entries and undefined behavior in index_mask"?
>
> And also here, fixed by:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=bbeb6e4323dad9b5e0ee9f60c223dd532e2403b1
>

Thanks Daniel, this crash is no longer occurring and I verified that commit
bbeb6e4323da fixed it, so let's allow syzbot to close this report too:

#syz fix: bpf, array: fix overflow in max_entries and undefined behavior in index_mask

- Eric