netdev - Re: [BUG] skb corruption and kernel panic at forwarding with 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]

Date:	Thu, 7 Jan 2016 15:04:14 +0300
From:	Konstantin Khlebnikov <koct9i@...il.com>
To:	Eric Dumazet <edumazet@...gle.com>
Cc:	Florian Westphal <fw@...len.de>,
	Thadeu Lima de Souza Cascardo <cascardo@...hat.com>,
	Cong Wang <xiyou.wangcong@...il.com>,
	Linux Kernel Network Developers <netdev@...r.kernel.org>,
	David Miller <davem@...emloft.net>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [BUG] skb corruption and kernel panic at forwarding with fragmentation

On Thu, Jan 7, 2016 at 2:59 PM, Eric Dumazet <edumazet@...gle.com> wrote:
> On Thu, Jan 7, 2016 at 6:38 AM, Konstantin Khlebnikov <koct9i@...il.com> wrote:
>>
>> Also I've found strange thing: reason of expanding skb->cb from 40 to
>> 48 bypes in 2006
>> 3e3850e989c5d2eb1aab6f0fd9257759f0f4cbc6 was that struct inet6_skb_parm does
>> not fit. But it's is only 24 bytes. Does some arches add pad after
>> each _u16 field?
>
> "struct inet6_skb_parm" is part of struct tcp_skb_cb
>
> This is why Patrick had to increase skb->cb[]

Whoa. Funny. TCP moves that chunk back and forward instead of just
putting it at the first place in struct.
--
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