Re: [syzbot] KASAN: use-after-free Read in copy_page_from_iter_atomic (2)

[David Sterba]

On Tue, Jun 14, 2022 at 09:17:57AM +0200, Christoph Hellwig wrote:
> On Mon, Jun 13, 2022 at 09:39:12PM +0200, David Sterba wrote:
> > On Fri, Jun 10, 2022 at 12:10:19AM -0700, syzbot wrote:
> > > syzbot has bisected this issue to:
> > > 
> > > commit 4cd4aed63125ccd4efc35162627827491c2a7be7
> > > Author: Christoph Hellwig <hch@xxxxxx>
> > > Date:   Fri May 27 08:43:20 2022 +0000
> > > 
> > >     btrfs: fold repair_io_failure into btrfs_repair_eb_io_failure
> > 
> > Josef also reported a crash and found a bug in the patch, now added as
> > fixup that'll be in for-next:
> 
> The patch looks correct to me.  Two things to note here:
> 
>  - I hadn't realized you had queued up the series.

I did a review and as it looked ok I added it to the for-next for
testing coverage, but I don't think I've sent any notice about that.

>  I've actually
>    started to merge some of my bio work with the bio split at
>    submission time work from Qu and after a few iterations I think
>    I would do the repair code a bit differently based on that.
>    Can you just drop the series for now?

Yeah, we consistently hit 2 crashes, one of them has a fix but the other
not, so I removed the topic branch from for-next. I'll wait for the
reworked version you mention.