netdev - Re: [PATCH v4 net] xen-netback: disable rogue vif in kthread context

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 for Android: free password hash cracker in your pocket

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

Message-ID: <1396429540.8667.263.camel@kazak.uk.xensource.com>
Date:	Wed, 2 Apr 2014 10:05:40 +0100
From:	Ian Campbell <Ian.Campbell@...rix.com>
To:	David Miller <davem@...emloft.net>
CC:	<wei.liu2@...rix.com>, <netdev@...r.kernel.org>,
	<xen-devel@...ts.xen.org>, <david.vrabel@...rix.com>,
	<zoltan.kiss@...rix.com>, <edwin@...rok.net>
Subject: Re: [PATCH v4 net] xen-netback: disable rogue vif in kthread context

On Tue, 2014-04-01 at 16:27 -0400, David Miller wrote:
> From: Wei Liu <wei.liu2@...rix.com>
> Date: Tue, 1 Apr 2014 12:46:12 +0100
> 
> > When netback discovers frontend is sending malformed packet it will
> > disables the interface which serves that frontend.
> > 
> > However disabling a network interface involving taking a mutex which
> > cannot be done in softirq context, so we need to defer this process to
> > kthread context.
> > 
> > This patch does the following:
> > 1. introduce a flag to indicate the interface is disabled.
> > 2. check that flag in TX path, don't do any work if it's true.
> > 3. check that flag in RX path, turn off that interface if it's true.
> > 
> > The reason to disable it in RX path is because RX uses kthread. After
> > this change the behavior of netback is still consistent -- it won't do
> > any TX work for a rogue frontend, and the interface will be eventually
> > turned off.
> > 
> > Also change a "continue" to "break" after xenvif_fatal_tx_err, as it
> > doesn't make sense to continue processing packets if frontend is rogue.
> > 
> > This is a fix for XSA-90.
> > 
> > Reported-by: Török Edwin <edwin@...rok.net>
> > Signed-off-by: Wei Liu <wei.liu2@...rix.com>
> 
> Applied.

Thanks.

Wei -- can you advise as to which stable trees this should be queued
for? Looks like 3.12 onwards according to
http://xenbits.xen.org/xsa/advisory-90.html which says the issue arose
between 3.11 and 3.12-rc1?

Cheers,
Ian.


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html