From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] ethernet: add sanity check before memory dereferencing
Date: Mon, 03 May 2010 23:11:56 -0700 (PDT)
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From: Changli Gao <xiaosuo@gmail.com>
Date: Tue,  4 May 2010 11:33:48 +0800

> add sanity check before memory dereferencing
> 
> Some callers of eth_type_trans() only can assure the length of the packets
> passed to it is not less than ETH_HLEN. We'd better check the packets length
> before dereferencing skb->data.
> 
> Signed-off-by: Changli Gao <xiaosuo@gmail.com>

We can deference skb->data for at least 16 bytes or so past the end
of the valid packet data area however we want.

It might give garbage values, but it will not cause a fault or any
kind.

We want to remove checks here, not add new ones Changli.