On Tue, Apr 09, 2013 at 01:47:52PM +0300, Mihail Costea wrote:
In the file distributed-arp-table.c, function
batadv_dat_snoop_incoming_arp_request, after creation of ARP reply
(skb_new = arp_create(...)) and testing if the creation was
successful, shouldn't exist a call to skb_reset_mac_header(skb_new),
just like in batadv_dat_snoop_outgoing_arp_request?
I've done something similar for NDP and I think that this is the line
that might generate a kernel panic (not sure yet, I might have to do
As I said, I'm not sure yet, and maybe my code might generate it. But
my question is why isn't here a skb_reset_mac_header as it is in the
skb_reset_mac_header() is invoked in batadv_send_skb_packet() right before
accessing the ethernet header. This is where DAT needs it, no further accesses
to the Ethernet header are done on its side.
I'd say that invocation at distributed-arp-table.c:843 can probably be avoided
(and there are
other similar cases in the rest of the code...)
skb_reset_mac_header() has to be invoked at the right moment in order to
correctly set the skb->mac_header pointer. In batman-adv we do this when
skb->data points at the beginning of the batman-adv header when we need to
access the Ethernet header for some reasons.
Be aware that some of the skb_* functions do invoke skb_reset_mac_header() on
their own (e.g. eth_type_trans).
..each of us alone is worth nothing..
Ernesto "Che" Guevara