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  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:	Tue, 28 Feb 2012 17:55:41 +0800
From:	RongQing Li <roy.qing.li@...il.com>
To:	Francois Romieu <romieu@...zoreil.com>
Cc:	netdev@...r.kernel.org
Subject: Re: [PATCH 2/2] ipv4: fix mss comparison

2012/2/28 Francois Romieu <romieu@...zoreil.com>:
> roy.qing.li@...il.com <roy.qing.li@...il.com> :
> [...]
>> diff --git a/net/ipv4/route.c b/net/ipv4/route.c
>> index 0489ced..c72f765 100644
>> --- a/net/ipv4/route.c
>> +++ b/net/ipv4/route.c
>> @@ -1914,8 +1914,8 @@ static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
>>       if (advmss == 0) {
>>               advmss = max_t(unsigned int, dst->dev->mtu - 40,
>>                              ip_rt_min_advmss);
>> -             if (advmss > 65535 - 40)
>> -                     advmss = 65535 - 40;
>> +             if (advmss > 65535 - sizeof(struct tcphdr))
>> +                     advmss = 65535 - sizeof(struct tcphdr);
>
> What would prevent net/ipv4/tcp_output.c::tcp_advertise_mss returning
> a value beyond 65535 - 40 ?
>

You are right, Please ignore this patch.
The biggest MSS should be (Total Length of ipv4 header -
sizeof(iphdr)- sizeof(tcphdr))

I mix up the Total Length of ipv4 header and Payload Length of ipv6 header.

> --
> Ueimor
--
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

Powered by blists - more mailing lists