openwrt-routing/batman-adv/patches/0024-batman-adv-fix-packet-...

44 lines
1.8 KiB
Diff

From: Matthias Schiffer <mschiffer@universe-factory.net>
Date: Tue, 23 Jan 2018 10:59:49 +0100
Subject: [PATCH] batman-adv: fix packet checksum in receive path
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: fe28a94c01e1 ("batman-adv: receive packets directly using skbs")
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Origin: upstream, https://git.open-mesh.org/batman-adv.git/commit/798174b15153afd88268f2f87811602f68b3f2c6
---
net/batman-adv/soft-interface.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 08432b14386a53c771c54b9eb38893d94c6f9b53..5da1a1c0f1efb5d95f31bc852b899f61e462feb1 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -470,13 +470,7 @@ 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,