From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 3/4] tipc: Optimize handling excess content on
 incoming messages
Date: Fri, 03 Sep 2010 12:55:33 -0700 (PDT)
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From: Paul Gortmaker <paul.gortmaker@windriver.com>
Date: Fri,  3 Sep 2010 14:33:41 -0400

> @@ -248,6 +248,7 @@ void tipc_net_route_msg(struct sk_buff *buf)
>  
>  	/* Handle message for another node */
>  	msg_dbg(msg, "NET>SEND>: ");
> +	pskb_trim(buf, msg_size(msg));
>  	tipc_link_send(buf, dnode, msg_link_selector(msg));
>  }

1) pskb_trim() can fail, you need to check the return value
   and act appropriately.

2) pskb_trim() can change all of the packet data pointers, so
   after you call it you need to reload any pointers to the
   packet data area.  At a minimum, you woull need to
   reload 'msg' in this code snippet.

   Otherwise 'msg' can point to freed up memory after the call.