Commit 4b3e33fc authored by Thomas Bogendoerfer's avatar Thomas Bogendoerfer Committed by Paolo Abeni
Browse files

ip6_tunnel: Fix broken GRO 



GRO code checks for matching layer 2 headers to see, if packet belongs
to the same flow and because ip6 tunnel set dev->hard_header_len
this check fails in cases, where it shouldn't. To fix this don't
set hard_header_len, but use needed_headroom like ipv4/ip_tunnel.c
does.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: default avatarThomas Bogendoerfer <tbogendoerfer@suse.de>
Link: https://patch.msgid.link/20240815151419.109864-1-tbogendoerfer@suse.de


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 807067bf

net/ipv6/ip6_tunnel.c

+7 −5
Original line number Diff line number Diff line
@@ -1507,7 +1507,8 @@ static void ip6_tnl_link_config(struct ip6_tnl *t) 
			tdev = __dev_get_by_index(t->net, p->link);



		if (tdev) {

			dev->hard_header_len = tdev->hard_header_len + t_hlen;

			dev->needed_headroom = tdev->hard_header_len +

				tdev->needed_headroom + t_hlen;

			mtu = min_t(unsigned int, tdev->mtu, IP6_MAX_MTU);



			mtu = mtu - t_hlen;
@@ -1731,7 +1732,9 @@ ip6_tnl_siocdevprivate(struct net_device *dev, struct ifreq *ifr, 
int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)

{

	struct ip6_tnl *tnl = netdev_priv(dev);

	int t_hlen;



	t_hlen = tnl->hlen + sizeof(struct ipv6hdr);

	if (tnl->parms.proto == IPPROTO_IPV6) {

		if (new_mtu < IPV6_MIN_MTU)

			return -EINVAL;
@@ -1740,10 +1743,10 @@ int ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) 
			return -EINVAL;

	}

	if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {

		if (new_mtu > IP6_MAX_MTU - dev->hard_header_len)

		if (new_mtu > IP6_MAX_MTU - dev->hard_header_len - t_hlen)

			return -EINVAL;

	} else {

		if (new_mtu > IP_MAX_MTU - dev->hard_header_len)

		if (new_mtu > IP_MAX_MTU - dev->hard_header_len - t_hlen)

			return -EINVAL;

	}

	WRITE_ONCE(dev->mtu, new_mtu);
@@ -1887,12 +1890,11 @@ ip6_tnl_dev_init_gen(struct net_device *dev) 
	t_hlen = t->hlen + sizeof(struct ipv6hdr);



	dev->type = ARPHRD_TUNNEL6;

	dev->hard_header_len = LL_MAX_HEADER + t_hlen;

	dev->mtu = ETH_DATA_LEN - t_hlen;

	if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))

		dev->mtu -= 8;

	dev->min_mtu = ETH_MIN_MTU;

	dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;

	dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len - t_hlen;



	netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);

	netdev_lockdep_set_classes(dev);