netdev - Re: [PATCH] ipv6: sr: fix get_srh() to comply with IPv6 standard "RFC 8200"

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Date:   Mon, 28 Aug 2017 23:27:37 +0200
From:   Ahmed Abdelsalam <amsalam20@...il.com>
To:     David Lebrun <david.lebrun@...ouvain.be>
Cc:     <davem@...emloft.net>, <yoshfuji@...ux-ipv6.org>,
        <netdev@...r.kernel.org>
Subject: Re: [PATCH] ipv6: sr: fix get_srh() to comply with IPv6 standard
 "RFC 8200"

On Mon, 28 Aug 2017 19:48:15 +0100
David Lebrun <david.lebrun@...ouvain.be> wrote:

> On 08/28/2017 07:20 PM, Ahmed Abdelsalam wrote:
> > This patch fixes the get_srh(), so it gets the segment routing header
> > regardless of its position in the chain of the extension headers in IPv6
> > packet, and makes sure that the IPv6 routing extension header is of
> > Type 4.
> 
> Ahmed,
> 
> You need to initialize srhoff to 0, otherwise ipv6_find_hdr() will crash
> the kernel by dereferencing an uninitialized pointer.
> 
> Please test your patches before submitting them.
> 
> Furthermore, your pskb_may_pull() check should happen right after the
> call to ipv6_find_hdr, with srhoff + sizeof(*srh) as argument. Once you
> have checked the SRH type, you can then do another pskb_may_pull with
> srhoff + len.
> 
> David
> 

Thanks David, 
 
I will address the comments and re-submit the patch after testing.

-- 
Ahmed