linux-kernel - Re: [PATCH] virtio-console: avoid DMA from stack

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]

Message-ID: <20170301200110.GA24754@vader.dhcp.thefacebook.com>
Date:   Wed, 1 Mar 2017 12:01:10 -0800
From:   Omar Sandoval <osandov@...ndov.com>
To:     "Michael S. Tsirkin" <mst@...hat.com>, Amit Shah <amit@...nel.org>
Cc:     virtualization@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org, kernel-team@...com
Subject: Re: [PATCH] virtio-console: avoid DMA from stack

On Wed, Feb 01, 2017 at 07:17:12PM +0530, Amit Shah wrote:
> On (Wed) 01 Feb 2017 [00:02:27], Omar Sandoval wrote:
> > From: Omar Sandoval <osandov@...com>
> > 
> > put_chars() stuffs the buffer it gets into an sg, but that buffer may be
> > on the stack. This breaks with CONFIG_VMAP_STACK=y (for me, it
> > manifested as printks getting turned into NUL bytes).
> 
> Seems reasonable.  I wonder since all implementations of hvc do a
> memcpy, if we can abstract it - but that'll need some work.
> 
> Reviewed-by: Amit Shah <amit.shah@...hat.com>
> 
> Michael, please add to the virtio queue.
> 
> 		Amit

Hi, Michael,

I don't see this in Linus' master or in your git tree, is it going to go
in for -rc1?

Thanks.