[041/145] net: bug fix for vlan + gro issue

From: Greg KH
Date: Fri Mar 12 2010 - 19:57:45 EST


2.6.32-stable review patch. If anyone has any objections, please let me know.

----------------
From: Ajit Khaparde <ajitk@xxxxxxxxxxxxxxxxx>

[ Upstream commit e76b69cc0133952c98aa1ad6330cacacd269fd64 ]

Traffic (tcp) doesnot start on a vlan interface when gro is enabled.
Even the tcp handshake was not taking place.
This is because, the eth_type_trans call before the netif_receive_skb
in napi_gro_finish() resets the skb->dev to napi->dev from the previously
set vlan netdev interface. This causes the ip_route_input to drop the
incoming packet considering it as a packet coming from a martian source.

I could repro this on 2.6.32.7 (stable) and 2.6.33-rc7.
With this fix, the traffic starts and the test runs fine on both vlan
and non-vlan interfaces.

CC: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
CC: Patrick McHardy <kaber@xxxxxxxxx>
Signed-off-by: Ajit Khaparde <ajitk@xxxxxxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
net/core/dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2630,7 +2630,7 @@ int napi_frags_finish(struct napi_struct
switch (ret) {
case GRO_NORMAL:
case GRO_HELD:
- skb->protocol = eth_type_trans(skb, napi->dev);
+ skb->protocol = eth_type_trans(skb, skb->dev);

if (ret == GRO_NORMAL)
return netif_receive_skb(skb);


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/