netdev - Re: [PATCH net-next] ipv6: protect skb->sk accesses from recursive dereference inside the 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]

Date:	Thu, 02 Apr 2015 02:56:16 +0200
From:	Hannes Frederic Sowa <hannes@...essinduktion.org>
To:	Eric Dumazet <eric.dumazet@...il.com>
Cc:	Cong Wang <cwang@...pensource.com>,
	netdev <netdev@...r.kernel.org>, Jiri Pirko <jiri@...nulli.us>
Subject: Re: [PATCH net-next] ipv6: protect skb->sk accesses from recursive
 dereference inside the stack



On Thu, Apr 2, 2015, at 02:48, Eric Dumazet wrote:
> On Thu, 2015-04-02 at 02:35 +0200, Hannes Frederic Sowa wrote:
> > On Thu, Apr 2, 2015, at 02:27, Eric Dumazet wrote: 
> > > orphaning skb just because they traverse a tunnel would be quite
> > > horrible.
> > 
> > Agreed, but we have some bits in the skb->sk pointer left for signaling
> > we are only keeping it around for destructor and upper layer
> > notifications. Destructors should be the only ones having to deal with
> > skb->sk and they can mask the bit. That would touch a lot of NULL
> > checks, though.
> 
> Have you checked net/sched/sch_fq.c per chance ?
> 
> skb->sk is not an opaque value.

Do you think that skb->sk access through skb->__sk & ~0x1ULL would slow
down the code too much?

--
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