From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Westphal <fw@strlen.de>
Subject: Re: [PATCH 2/4] net: make skb_gso_segment error handling more robust
Date: Mon, 20 Oct 2014 09:05:04 +0200
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To: David Miller <davem@davemloft.net>
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David Miller <davem@davemloft.net> wrote:
> From: Florian Westphal <fw@strlen.de>
> Date: Sun, 19 Oct 2014 22:42:19 +0200
> 
> > skb_gso_segment has three possible return values:
> > 1. a pointer to the first segmented skb
> > 2. an errno value (IS_ERR())
> > 3. NULL.  This can happen when GSO is used for header verification.
> > 
> > However, several callers currently test IS_ERR instead of IS_ERR_OR_NULL
> > and would oops when NULL is returned.
> > 
> > Note that these call sites should never actually see such a NULL return
> > value; all callers mask out the GSO bits in the feature argument.
> > 
> > However, in the past, there have been issues with some protocol handlers
> > erronously not respecting the specified feature mask in some cases.
> > 
> > Signed-off-by: Florian Westphal <fw@strlen.de>
> 
> I don't think it makes sense to return PTR_ERR(p) when
> p is NULL.

Good point. Will respin.