netdev - Re: [PATCH net] tcp: initialize tp->copied_seq in case of cross SYN connection

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] [day] [month] [year] [list]

Date:	Mon, 30 Nov 2015 15:35:29 -0500 (EST)
From:	David Miller <davem@...emloft.net>
To:	eric.dumazet@...il.com
Cc:	netdev@...r.kernel.org, dvyukov@...gle.com
Subject: Re: [PATCH net] tcp: initialize tp->copied_seq in case of cross
 SYN connection

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Thu, 26 Nov 2015 08:18:14 -0800

> From: Eric Dumazet <edumazet@...gle.com>
> 
> Dmitry provided a syzkaller (http://github.com/google/syzkaller)
> generated program that triggers the WARNING at 
> net/ipv4/tcp.c:1729 in tcp_recvmsg() :
> 
> WARN_ON(tp->copied_seq != tp->rcv_nxt &&
>         !(flags & (MSG_PEEK | MSG_TRUNC)));
> 
> His program is specifically attempting a Cross SYN TCP exchange,
> that we support (for the pleasure of hackers ?), but it looks we
> lack proper tcp->copied_seq initialization.
> 
> Thanks again Dmitry for your report and testings.
> 
> Signed-off-by: Eric Dumazet <edumazet@...gle.com>
> Reported-by: Dmitry Vyukov <dvyukov@...gle.com>
> Tested-by: Dmitry Vyukov <dvyukov@...gle.com>

Applied and queued up for -stable, thanks Eric!
--
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