Re: [PATCHv2 0/2] Fix crash due to vma_is_anonymous() false-positives

From: Kirill A. Shutemov
Date: Thu Jul 12 2018 - 11:08:08 EST


On Thu, Jul 12, 2018 at 05:56:24PM +0300, Kirill A. Shutemov wrote:
>
> Fix crash found by syzkaller.
>
> The fix allows to remove ->vm_ops checks.
>
> v2:
> - Catch few more cases where we need to initialize ->vm_ops:
> + nommu;
> + ia64;
> - Make sure that we initialize ->vm_ops even if ->mmap failed.
> We need ->vm_ops in error path too.

Just to be clear: it *should* help found issues, but I don't have setup to
test nommu changes.

And ion-related bug was actually caused by fault injection that failed
page allocation and ->mmap not setting ->vm_ops. It should be fine now.
But again I wasn't able to trigger the exact situation.

--
Kirill A. Shutemov