Re: Fw: Local Denial-of-Service attack against Linux

From: Manfred Spraul (manfreds@colorfullife.com)
Date: Sun Mar 26 2000 - 05:40:08 EST

Alexey Kuznetosv wrote:
> > The code is really weird:
> >
> > * sk->sndbuf is initialized to wmem_default, but sock_setsockopt() sets
> > sk->sndbuf to 2*the user supplied number.
>
> Yes. What is strange here?
>

1) setsockopt(SO_SNDBUF,x);
        y=getsockopt(SO_SNDBUF);

now y=2*x

2) or
        x = get_wmem_default_with_sysctl();
        setsockopt(SO_SNDBUF,x);

Doesn't restore the original send buffer, it doubles the send buffer
size.

If we set the internal send buffers to 2* the user space number, then
should do that everywhere. 

--
	Manfred

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