From: Stephen Hemminger <shemminger@xxxxxxxxxxxxxxxxxxxx> Date: Mon, 3 Jan 2011 10:15:33 -0800 > On Mon, 03 Jan 2011 09:22:14 -0800 (PST) > David Miller <davem@xxxxxxxxxxxxx> wrote: > >> From: Changli Gao <xiaosuo@xxxxxxxxx> >> Date: Mon, 3 Jan 2011 18:44:59 +0800 >> >> > On Sat, Jan 1, 2011 at 3:10 AM, David Miller <davem@xxxxxxxxxxxxx> wrote: >> >> From: Changli Gao <xiaosuo@xxxxxxxxx> >> >> Date: Sat, 25 Dec 2010 21:41:30 +0800 >> >> >> >>> Since nf_bridge_maybe_copy_header() may change the length of skb, >> >>> we should check the length of skb after it to handle the ppoe skbs. >> >>> >> >>> Signed-off-by: Changli Gao <xiaosuo@xxxxxxxxx> >> >> >> >> This is really strange. >> >> >> >> packet_length() subtracts VLAN_HLEN from the value it returns, so the >> >> correct fix seems to be to make this function handle the PPPOE case >> >> too. >> >> >> > >> > It is correct. The actual MTU of 802.1q frame is 4 bytes larger. For >> > example, the MTU of ethernet is normally 1500, however the actual MTU >> > of the 802.1Q is 1504. >> >> Yes, I understand this, but I don't see why packet_length() cannot >> simply account for PPPOE's encapsulation overhead just as it does for >> VLAN's special MTU considerations. > > Because PPPOE happens afterwards and is not part the calculation. > The check should be moved until after skb has reached final form. That works for me. _______________________________________________ Bridge mailing list Bridge@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/bridge
