netdev - Re: [PATCH 8/8] bridge: Fix netpoll support

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: <4C1755C1.3060804@redhat.com>
Date:	Tue, 15 Jun 2010 18:28:17 +0800
From:	Cong Wang <amwang@...hat.com>
To:	Herbert Xu <herbert@...dor.hengli.com.au>
CC:	"Michael S. Tsirkin" <mst@...hat.com>,
	Qianfeng Zhang <frzhang@...hat.com>,
	"David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org,
	Stephen Hemminger <shemminger@...tta.com>,
	Matt Mackall <mpm@...enic.com>,
	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>
Subject: Re: [PATCH 8/8] bridge: Fix netpoll support

On 06/11/10 10:12, Herbert Xu wrote:
> bridge: Fix netpoll support
>
> There are multiple problems with the newly added netpoll support:
>
> 1) Use-after-free on each netpoll packet.
> 2) Invoking unsafe code on netpoll/IRQ path.
> 3) Breaks when netpoll is enabled on the underlying device.
>
> This patch fixes all of these problems.  In particular, we now
> allocate proper netpoll structures for each underlying device.
>
> We only allow netpoll to be enabled on the bridge when all the
> devices underneath it support netpoll.  Once it is enabled, we
> do not allow non-netpoll devices to join the bridge (until netpoll
> is disabled again).
>


This is a good idea!

> This allows us to do away with the npinfo juggling that caused
> problem number 1.
>
> Incidentally this patch fixes number 2 by bypassing unsafe code
> such as multicast snooping and netfilter.


Not sure if I understand problem 2) and 3), this patch is not easy
to review. So, what's the point of adding ->np to struct net_bridge_port?
since we already have p->dev->npinfo->netpoll?

Thanks!

--
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