[PATCH V4 1/2] netfilter: xt_AUDIT: use consistent ipv4 network offset

[Richard Guy Briggs]

On 2017-03-22 12:11, Pablo Neira Ayuso wrote:
> On Wed, Mar 22, 2017 at 03:05:36AM -0400, Richard Guy Briggs wrote:
> > Even though the skb->data pointer has been moved from the link layer
> > header to the network layer header, use the same method to calculate the
> > offset in ipv4 and ipv6 routines.
> > 
> > Signed-off-by: Richard Guy Briggs <rgb at redhat.com>
> > ---
> >  net/netfilter/xt_AUDIT.c |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> > 
> > diff --git a/net/netfilter/xt_AUDIT.c b/net/netfilter/xt_AUDIT.c
> > index 4973cbd..cdb7cee 100644
> > --- a/net/netfilter/xt_AUDIT.c
> > +++ b/net/netfilter/xt_AUDIT.c
> > @@ -76,7 +76,7 @@ static void audit_ip4(struct audit_buffer *ab, struct sk_buff *skb)
> >  	struct iphdr _iph;
> >  	const struct iphdr *ih;
> >  
> > -	ih = skb_header_pointer(skb, 0, sizeof(_iph), &_iph);
> > +	ih = skb_header_pointer(skb, skb_network_offset(skb), sizeof(_iph), &_iph);
> 
> This update is completely pointless.

Its point is to be consistent with audit_ip6() and to prevent further
time consumed by confusion and head-scratching.  I know it is slightly
slower with an identical result.

> If you want I can place it in nf-next, your call.

I'd prefer to bring it through the audit-next tree to avoid the merge
conflict.

- RGB

--
Richard Guy Briggs <rgb at redhat.com>
Kernel Security Engineering, Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635