netdev - Re: [FYI] xfrm: Don't lookup sk_policy for timewait sockets

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: <20150409.170720.1374561715105253435.davem@davemloft.net>
Date:	Thu, 09 Apr 2015 17:07:20 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	fw@...len.de
Cc:	eric.dumazet@...il.com, sebastian.poehn@...il.com,
	netdev@...r.kernel.org
Subject: Re: [FYI] xfrm: Don't lookup sk_policy for timewait sockets

From: Florian Westphal <fw@...len.de>
Date: Thu, 9 Apr 2015 21:14:41 +0200

> I re-introduced this in fd158d79d33d3c under the assumption
> that the input path handles skb->sk timewait sockets correctly
> after all the early demux changes, afaics tcp edemux can also
> assign skb->sk timewait sockets.
> 
> Also, reporter mentions 3.8 as affected which should not assign
> tw sockets to skb->sk.
> 
> Even more strange, the reporters backtrace seems to indicate
> crash at end of forward path.
> 
> Sebastian, can you disable tw assignment via TPROXY in 3.12 just
> to see if it makes a difference?
> 
> [ not doing the assignment is safe provided you still set tproxy mark
>   on the skb; policy routing will ensure local delivery ].

My assumption in my analysis is that TPROXY writes the socket to
skb->sk, and it is also being forwarded.  And yes this is based
upon his backtrace.

--
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