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From: David Miller <davem@davemloft.net>
Subject: Re: possible kernel oops from user MSS
Date: Fri, 12 Nov 2010 15:26:07 -0800 (PST)
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From: Min Zhang <mzhang@mvista.com>
Date: Fri, 12 Nov 2010 14:59:58 -0800

> Regarding commit 7a1abd08d52fdeddb3e9a5a33f2f15cc6a5674d2 ("tcp:
> Increase TCP_MAXSEG socket option minimum"). What is the reason
> TCP_MAXSEG minimum be 64? Isn't the exact be 40 which is
> TCPOLEN_MD5SIG_ALIGNED(20) + TCPOLEN_TSTAMP_ALIGNED(12) + 8?
> 
> Or is it better to use TCP_MIN_MSS from tcp.h:
> 
> /* Minimal accepted MSS. It is (60+60+8) - (20+20). */
> #define TCP_MIN_MSS        88U

I suppose TCP_MIN_MSS would be better to use, I'll make that
change, thanks.