Re: [PATCH v2 0/2] iter revert problems
From: Jens Axboe
Date: Mon Aug 16 2021 - 11:35:20 EST
On 8/12/21 2:40 PM, Pavel Begunkov wrote:
> For the bug description see 2/2. As mentioned there the current problems
> is because of generic_write_checks(), but there was also a similar case
> fixed in 5.12, which should have been triggerable by normal
> write(2)/read(2) and others.
>
> It may be better to enforce reexpands as a long term solution, but for
> now this patchset is quickier and easier to backport.
>
> v2: don't fail it has been justly fully reverted
Al, what do you think of this approach? It'll fix the issue, but might be
cleaner to have iov->truncated actually track the truncated size. That'd
make it a more complete solution, at the expense of bloat iov_iter which
this version will not.
--
Jens Axboe