linux-kernel - Re: [PATCH] ipv4: avoid divide 0 error in tcp_incr

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: <20141101.170605.1353817217163030327.davem@davemloft.net>
Date:	Sat, 01 Nov 2014 17:06:05 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	chenweilong@...wei.com
Cc:	kuznet@....inr.ac.ru, jmorris@...ei.org, yoshfuji@...ux-ipv6.org,
	kaber@...sh.net, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] ipv4: avoid divide 0 error in tcp_incr_quickack

From: Chen Weilong <chenweilong@...wei.com>
Date: Fri, 31 Oct 2014 22:50:47 +0800

> From: Weilong Chen <chenweilong@...wei.com>
> 
> We got a problem like this:
>  [ffff8801c1a05570] machine_kexec at ffffffff81025039
>  [ffff8801c1a055d0] crash_kexec at ffffffff8109b253
>  [ffff8801c1a056a0] oops_end at ffffffff81442aed
>  [ffff8801c1a056d0] die at ffffffff81005603
>  [ffff8801c1a05700] do_trap at ffffffff81442448
>  [ffff8801c1a05760] do_divide_error at ffffffff81002c10
>  [ffff8801c1a05888] tcp_send_dupack at ffffffff81385e44
>  [ffff8801c1a058c8] tcp_validate_incoming at ffffffff813886b5
>  [ffff8801c1a05908] tcp_rcv_state_process at ffffffff8138d0b7
>  [ffff8801c1a05958] tcp_child_process at ffffffff81397255
>  [ffff8801c1a05988] tcp_v4_do_rcv at ffffffff81395a70
>  [ffff8801c1a059d8] tcp_v4_rcv at ffffffff81396fc8
>  [ffff8801c1a05a48] ip_local_deliver_finish at ffffffff813746e9
>  [ffff8801c1a05a78] ip_local_deliver at ffffffff81374a20
>  [ffff8801c1a05aa8] ip_rcv_finish at ffffffff81374389
>  [ffff8801c1a05ad8] ip_rcv at ffffffff81374c78
> There was a wrong ack packet coming during TCP handshake. The socket's state
> was TCP_SYN_RECV, its rcv_mss was not initialize yet. So
> tcp_send_dupack -> tcp_enter_quickack_mode got a divide 0 error.
> This patch add a state check before tcp_enter_quickack_mode.
> 
> Signed-off-by: Weilong Chen <chenweilong@...wei.com>

Can you please resubmit this, properly CC:'ing netdev@...r.kernel.org this
time?

Thank you.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/