netdev - Re: [PATCH v3] ip: fix truesize mismatch in ip fragmentation

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: <20100921.151534.183050170.davem@davemloft.net>
Date:	Tue, 21 Sep 2010 15:15:34 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	jarkao2@...il.com
Cc:	eric.dumazet@...il.com, nbowler@...iptictech.com,
	linux-kernel@...r.kernel.org, netdev@...r.kernel.org,
	kaber@...sh.net
Subject: Re: [PATCH v3] ip: fix truesize mismatch in ip fragmentation

From: Jarek Poplawski <jarkao2@...il.com>
Date: Tue, 21 Sep 2010 21:21:54 +0200

> On Tue, Sep 21, 2010 at 08:47:45PM +0200, Eric Dumazet wrote:
>> [PATCH v4] ip: fix truesize mismatch in ip fragmentation
>> 
>> Special care should be taken when slow path is hit in ip_fragment() :
>> 
>> When walking through frags, we transfert truesize ownership from skb to
>> frags. Then if we hit a slow_path condition, we must undo this or risk
>> uncharging frags->truesize twice, and in the end, having negative socket
>> sk_wmem_alloc counter, or even freeing socket sooner than expected.
>> 
>> Many thanks to Nick Bowler, who provided a very clean bug report and
>> test program.
>> 
>> Thanks to Jarek for reviewing my first patch and providing a V2
>> 
>> While Nick bisection pointed to commit 2b85a34e911 (net: No more
>> expensive sock_hold()/sock_put() on each tx), underlying bug is older
>> (2.6.12-rc5)
>> 
>> A side effect is to extend work done in commit b2722b1c3a893e
>> (ip_fragment: also adjust skb->truesize for packets not owned by a
>> socket) to ipv6 as well.
>> 
>> Reported-and-bisected-by: Nick Bowler <nbowler@...iptictech.com>
>> Tested-by: Nick Bowler <nbowler@...iptictech.com>
>> Signed-off-by: Eric Dumazet <eric.dumazet@...il.com>
>> CC: Jarek Poplawski <jarkao2@...il.com>
>> CC: Patrick McHardy <kaber@...sh.net>
> 
> Looks perfect to me.

Great work everyone!

Applied, 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