linux-kernel - Re: general protection fault in mas_empty_area

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Mon, 22 Apr 2024 14:53:17 -0400
From: "Liam R. Howlett" <Liam.Howlett@...cle.com>
To: Marius Fleischer <fleischermarius@...il.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>, maple-tree@...ts.infradead.org,
        linux-kernel@...r.kernel.org, syzkaller@...glegroups.com,
        harrisonmichaelgreen@...il.com
Subject: Re: general protection fault in mas_empty_area_rev

* Marius Fleischer <fleischermarius@...il.com> [240422 14:07]:
> Hi Liam,
> 
> On Mon, 22 Apr 2024 at 10:05, Liam R. Howlett <Liam.Howlett@...cle.com> wrote:
> > * Liam R. Howlett <Liam.Howlett@...cle.com> [240422 11:25]:
> > > * Marius Fleischer <fleischermarius@...il.com> [240422 11:11]:
> > > > Hi Liam,
> > > >
> > > > Thank you so much for the response!
> > > >
> > > > > >
> > > > > > Crash log:
> > > > > >
> > > > > > general protection fault, probably for non-canonical address
> > > > > > 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI
> > > > > >
> > > > > > KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
> > > > > >
> > > > > > CPU: 0 PID: 79545 Comm: syz-executor.0 Not tainted 6.9.0-rc4-dirty #3
> > > > >
> > > > > This indicates that you built with your own patches.  Could you test an
> > > > > unmodified 6.9.0-rc4 with your setup?
> > > > >
> > > >
> > > > I'm very sorry for this oversight. I had applied the patches for another bug
> > > > from this conversation
> > > > (https://lore.kernel.org/all/20240404070702.2744-3-osalvador@suse.de/T/#m480f21ab850996395082d0faab7f624f45b83781)
> > > > I will test the reproducer without these patches and get back to you!
> > >
> > > After testing with your config, I can see that those fixes are needed to
> > > boot.
> > >
> > > I am going to try 6.9-rc5 with your configuration and see if I can
> > > trigger the issue there.
> > >
> >
> > The reproducer does not trigger for me with your configuration and
> > reproducer.
> >
> > Does it still happen for you in 6.9-rc5?
> >
> You are right, indeed, I was not able to boot v6.9-rc4 without the fixes.
> 
> I tested the reproducer on 6.9-rc5 (ed30a4a51bb196781c8058073ea720133a65596f)
> and it still triggers the crash in my setup. How can I help you
> further troubleshoot
> this issue?

Can you try the attached patch and see if that stops the crash?

Thanks,
Liam

View attachment "fix_20240422.patch" of type "text/x-diff" (919 bytes)