[NET] gso: Fix up GSO packets with broken checksums
Certain subsystems in the stack (e.g., netfilter) can break the partial
checksum on GSO packets. Until they're fixed, this patch allows this to
work by recomputing the partial checksums through the GSO mechanism.
Once they've all been converted to update the partial checksum instead of
clearing it, this workaround can be removed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 318d467..c84a320 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1097,6 +1097,40 @@
EXPORT_SYMBOL(inet_sk_rebuild_header);
+static int inet_gso_send_check(struct sk_buff *skb)
+{
+ struct iphdr *iph;
+ struct net_protocol *ops;
+ int proto;
+ int ihl;
+ int err = -EINVAL;
+
+ if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
+ goto out;
+
+ iph = skb->nh.iph;
+ ihl = iph->ihl * 4;
+ if (ihl < sizeof(*iph))
+ goto out;
+
+ if (unlikely(!pskb_may_pull(skb, ihl)))
+ goto out;
+
+ skb->h.raw = __skb_pull(skb, ihl);
+ iph = skb->nh.iph;
+ proto = iph->protocol & (MAX_INET_PROTOS - 1);
+ err = -EPROTONOSUPPORT;
+
+ rcu_read_lock();
+ ops = rcu_dereference(inet_protos[proto]);
+ if (likely(ops && ops->gso_send_check))
+ err = ops->gso_send_check(skb);
+ rcu_read_unlock();
+
+out:
+ return err;
+}
+
static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int features)
{
struct sk_buff *segs = ERR_PTR(-EINVAL);
@@ -1162,6 +1196,7 @@
static struct net_protocol tcp_protocol = {
.handler = tcp_v4_rcv,
.err_handler = tcp_v4_err,
+ .gso_send_check = tcp_v4_gso_send_check,
.gso_segment = tcp_tso_segment,
.no_policy = 1,
};
@@ -1208,6 +1243,7 @@
static struct packet_type ip_packet_type = {
.type = __constant_htons(ETH_P_IP),
.func = ip_rcv,
+ .gso_send_check = inet_gso_send_check,
.gso_segment = inet_gso_segment,
};