Re: Bug report - slab-out-of-bounds in vcs_scr_readw

From: Or Cohen <orcohen@paloaltonetworks.com>
To: Nicolas Pitre <nico@fluxnic.net>
Cc: Greg KH <gregkh@linuxfoundation.org>,
	jslaby@suse.com, textshell@uchuujin.de,
	Daniel Vetter <daniel.vetter@ffwll.ch>,
	sam@ravnborg.org, mpatocka@redhat.com, ghalat@redhat.com,
	linux-kernel@vger.kernel.org, jwilk@jwilk.net,
	Nadav Markus <nmarkus@paloaltonetworks.com>,
	syzkaller@googlegroups.com
Subject: Re: Bug report - slab-out-of-bounds in vcs_scr_readw
Date: Mon, 4 Nov 2019 08:15:18 -0800	[thread overview]
Message-ID: <CAM6JnLdrzCPOYyfTdmriFo7cRaGM4p2OEPd_0MHa3_WemamffA@mail.gmail.com> (raw)
In-Reply-To: <nycvar.YSQ.7.76.1911041648280.30289@knanqh.ubzr>

@gregkh@linuxfoundation.org @nico@fluxnic.net  - Thanks for the quick response.
@gregkh@linuxfoundation.org  - Regarding your question, I don't think
the 1 byte buffer is related to the problem. (  it's just was there in
the initial reproducer the fuzzer created, and I forgot to remove it
while reducing code from the reproducer ).
I think the problem is related to the huge size argument , which
influences  the initialization of "this_round".

On Mon, Nov 4, 2019 at 7:50 AM Nicolas Pitre <nico@fluxnic.net> wrote:
>
> On Mon, 4 Nov 2019, Greg KH wrote:
>
> > On Mon, Nov 04, 2019 at 04:39:55AM -0800, Or Cohen wrote:
> > > Hi,
> > > I discovered a OOB access bug using Syzkaller and decided to report it,
> > > as I could not find a similar report in syzkaller mailing list,
> > > syzkaller-bugs mailing list
> [...]
> >
> > I am at another conference at the moment and can't look at this much
> > now, will try to later this week...
>
> I'll looking into it now.
>
>
> Nicolas