Re: [syzbot] general protection fault in list_lru_add

From: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
To: syzbot <syzbot+f8c45ccc7d5d45fc5965@syzkaller.appspotmail.com>,
	syzkaller-bugs@googlegroups.com,
	Muchun Song <songmuchun@bytedance.com>,
	Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Dmitry Vyukov <dvyukov@google.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux-MM <linux-mm@kvack.org>,
	syzkaller-bugs <syzkaller-bugs@googlegroups.com>
Subject: Re: [syzbot] general protection fault in list_lru_add
Date: Fri, 25 Mar 2022 06:47:36 +0100	[thread overview]
Message-ID: <12984828.uLZWGnKmhe@leap> (raw)
In-Reply-To: <CAHk-=whxaFX4nqnE-SLHTGKyqejvbrhYx5sagcxWd+UWCMf8dg@mail.gmail.com>

On giovedì 24 marzo 2022 20:45:00 CET Linus Torvalds wrote:
> On Thu, Mar 24, 2022 at 12:41 PM syzbot
> <syzbot+f8c45ccc7d5d45fc5965@syzkaller.appspotmail.com> 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".
> 
>              Linus
> 
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> 

No, not at all, Linus!

Unless I'm still sleeping with wide open eyes (it's 6.30 AM here), you are misunderstanding 
this message from Syzbot :)

This message means that Syzbot has applied and tested the patch and now is not 
anymore able to trigger any bug. In summation it means that the patch works properly.

Now Muchun should simply submit his patch (the usual way) with a "Fixes:" tag 
and with "Reported-and-tested-by: syzbot+f8c45ccc7d5d45fc5965@syzkaller.appspotmail.com".

Thanks,

Fabio M. De Francesco