KASAN: slab-out-of-bounds Write in vgacon_scroll

[Sergey Senozhatsky]

On (20/01/29 23:15), Sergey Senozhatsky wrote:
> Date: Wed, 29 Jan 2020 23:15:17 +0900
> From: Sergey Senozhatsky <sergey.senozhatsky at gmail.com>
> To: Bartlomiej Zolnierkiewicz <b.zolnierkie at samsung.com>
> Cc: Petr Mladek <pmladek at suse.com>, anon anon <742991625abc at gmail.com>,
>  wangkefeng.wang at huawei.com, sergey.senozhatsky at gmail.com,
>  syzkaller at googlegroups.com, linux-kernel at vger.kernel.org,
>  dri-devel at lists.freedesktop.org, linux-fbdev at vger.kernel.org
> Subject: Re: KASAN: slab-out-of-bounds Write in vgacon_scroll
> Message-ID: <20200129141517.GA13721 at jagdpanzerIV.localdomain>
> 
> On (20/01/28 15:58), Bartlomiej Zolnierkiewicz wrote:
> [..]
> > 
> > Help is welcomed as I'm not going to look at it in the foreseeable future
> > (I'm busy enough with other things).
> > 
> > > (dri-devel at lists.freedesktop.org or linux-fbdev at vger.kernel.org) into CC?
> > 
> > Added to Cc:, thanks.
> 
> Hmm. There is something strange about it. I use vga console quite
> often, and scrolling happens all the time, yet I can't get the same
> out-of-bounds report (nor have I ever seen it in the past), even with
> the reproducer. Is it supposed to be executed as it is, or are there
> any preconditions? Any chance that something that runs prior to that
> reproducer somehow impacts the system? Just asking.

These questions were addressed to anon anon (742991625abc at gmail.com),
not to Bartlomiej.

	-ss