redonkable
/
remarkable-linux
1
0
Fork 0
Code Releases Activity

batman-adv: fix packet checksum in receive path 

[ Upstream commit abd6360591 ]

eth_type_trans() internally calls skb_pull(), which does not adjust the
skb checksum; skb_postpull_rcsum() is necessary to avoid log spam of the
form "bat0: hw csum failure" when packets with CHECKSUM_COMPLETE are
received.

Note that in usual setups, packets don't reach batman-adv with
CHECKSUM_COMPLETE (I assume NICs bail out of checksumming when they see
batadv's ethtype?), which is why the log messages do not occur on every
system using batman-adv. I could reproduce this issue by stacking
batman-adv on top of a VXLAN interface.

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Tested-by: Maximilian Wilhelm <max@sdn.clinic>
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pull/10/head
Matthias Schiffer 2018-01-23 10:59:49 +01:00 committed by Greg Kroah-Hartman
parent 879a73b10a
commit ee7a88fc77
1 changed files with 1 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
net/batman-adv/soft-interface.c
View File

@ -451,13 +451,7 @@ void batadv_interface_rx(struct net_device *soft_iface,
/* skb->dev & skb->pkt_type are set here */
skb->protocol = eth_type_trans(skb, soft_iface);
/* should not be necessary anymore as we use skb_pull_rcsum()
* TODO: please verify this and remove this TODO
* -- Dec 21st 2009, Simon Wunderlich
*/
/* skb->ip_summed = CHECKSUM_UNNECESSARY; */
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
batadv_inc_counter(bat_priv, BATADV_CNT_RX);
batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,