Re: IPv4: ip_options_compile() how can we avoid blowing up on a NULL skb???

[Herbert Xu]

Jesper Juhl <jesper.juhl@xxxxxxxxx> wrote:
> 
> So if 'skb' is NULL, the only route I see that doesn't cause a NULL
> pointer deref is if  (opt != NULL)  and at the same time
> (opt->is_data != NULL)  .   Is that guaranteed in any way?  If now,
> how come we don't blow up regularly?

Yes that's how it's supposed to be used.  This function either constructs
an opts structure from a packet, or it verifies the validity of a suspect
opts structure (without a packet).  In the latter case, both opt and
opt->is_data should be non-zero.

Cheers,
-- 
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