Re: [syzbot] general protection fault in list_lru_add

[Linus Torvalds]

On Thu, Mar 24, 2022 at 12:45 PM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Thu, Mar 24, 2022 at 12:41 PM syzbot
> <syzbot+f8c45ccc7d5d45fc5965@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > syzbot has tested the proposed patch and the reproducer did not trigger any issue:
>
> Heh, well that's unfortunate.
>
> I think the issue is that it triggered a new BUG() that didn't match
> the previous NULL pointer dereference, so it thinks things are
> "fixed".

Oh, no, it's because it used the truncated patch that didn't do anything:

> patch:          https://syzkaller.appspot.com/x/patch.diff?x=1208043d700000

and maybe (due to the racy nature) nothing actually happened.

             Linus