From: Yossi Kuperman <yoss...@mellanox.com>
xfrm6_transport_finish rebuilds the IPv6 header based on the
original one and pushes it back without fixing skb->csum.
Therefore, CHECKSUM_COMPLETE is no longer valid and the packet
gets dropped.
Fix skb->csum by calling skb_postpush_rcsum.
Note: A valid IPv4 header has checksum 0, unlike IPv6. Thus,
the change is not needed in the sibling xfrm4_transport_finish
function.
Signed-off-by: Yossi Kuperman <yoss...@mellanox.com>
Signed-off-by: Ilan Tayari <il...@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klass...@secunet.com>
---
net/ipv6/xfrm6_input.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 3ef5d91..f95943a 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -34,6 +34,7 @@ EXPORT_SYMBOL(xfrm6_rcv_spi);
int xfrm6_transport_finish(struct sk_buff *skb, int async)
{
struct xfrm_offload *xo = xfrm_offload(skb);
+ int nhlen = skb->data - skb_network_header(skb);
skb_network_header(skb)[IP6CB(skb)->nhoff] =
XFRM_MODE_SKB_CB(skb)->protocol;
@@ -43,8 +44,9 @@ int xfrm6_transport_finish(struct sk_buff *skb, int async)
return 1;
#endif
- __skb_push(skb, skb->data - skb_network_header(skb));
+ __skb_push(skb, nhlen);
ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_postpush_rcsum(skb, skb_network_header(skb), nhlen);
if (xo && (xo->flags & XFRM_GRO)) {
skb_mac_header_rebuild(skb);
--
2.7.4
