Re: Re: KASAN: soft lockup in paste_selection

From: Greg KH
Date: Mon May 15 2023 - 08:01:31 EST


On Mon, May 15, 2023 at 03:26:29PM +0800, Qiumiao Zhang wrote:
> On Fri, May 12, 2023 at 11:33:26AM +0000, gregkh wrote:
> >> Hello,
> >>
> >> We found the following issue using syzkaller on Linux v5.10.0.
> >
> > 5.10.0 is very old and obsolete and over 20 thousand patches old.
> > Please, if you are testing LTS kernels, use the latest one.
> >
> >> A similar issue was found in function `paste_selection` before and I
> >> believe they are the same.
> >> (https://lore.kernel.org/all/000000000000fe769905d315a1b7@xxxxxxxxxx/)
> >>
> >> Unfortunately, no one seems to be paying attention to this issue.
> >
> > Do you have a proposed patch for this fix now that you have a way to reproduce this? Do you see this in real situations or only in > fault-injection systems running syzbot?
> >
> > And can you reproduce this on 6.4-rc1? Do you have a reproducer?
> >
> > thanks,
> >
> > greg k-h
>
> I see this issue only in fault-injection systems running syzbot. And I can reproduce this on 6.4-rc1.

fault-injection systems are "fake" and for many issues in the
tty/console layer, we really do not care about them as they the failures
can never be triggered in real life.

Are you sure this is not such a issue?

Try to fix this up by adding the needed "error handling" to the place
where the fault injection was causing the failure, and see if that
really is realistic or not.

good luck!

greg k-h