1 files changed, 57 insertions, 20 deletions

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 4d2025f7ec57..5b1481be0282 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -49,12 +49,6 @@
 #include <net/gre.h>
 #include <net/dst_metadata.h>
 
-#if IS_ENABLED(CONFIG_IPV6)
-#include <net/ipv6.h>
-#include <net/ip6_fib.h>
-#include <net/ip6_route.h>
-#endif
-
 /*
    Problems & solutions
    --------------------
@@ -144,6 +138,7 @@ static void ipgre_err(struct sk_buff *skb, u32 info,
 	const struct iphdr *iph;
 	const int type = icmp_hdr(skb)->type;
 	const int code = icmp_hdr(skb)->code;
+	unsigned int data_len = 0;
 	struct ip_tunnel *t;
 
 	switch (type) {
@@ -169,6 +164,7 @@ static void ipgre_err(struct sk_buff *skb, u32 info,
 	case ICMP_TIME_EXCEEDED:
 		if (code != ICMP_EXC_TTL)
 			return;
+		data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
 		break;
 
 	case ICMP_REDIRECT:
@@ -187,6 +183,13 @@ static void ipgre_err(struct sk_buff *skb, u32 info,
 	if (!t)
 		return;
 
+#if IS_ENABLED(CONFIG_IPV6)
+       if (tpi->proto == htons(ETH_P_IPV6) &&
+           !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,
+				       type, data_len))
+               return;
+#endif
+
 	if (t->parms.iph.daddr == 0 ||
 	    ipv4_is_multicast(t->parms.iph.daddr))
 		return;
@@ -217,12 +220,14 @@ static void gre_err(struct sk_buff *skb, u32 info)
 	 * by themselves???
 	 */
 
+	const struct iphdr *iph = (struct iphdr *)skb->data;
 	const int type = icmp_hdr(skb)->type;
 	const int code = icmp_hdr(skb)->code;
 	struct tnl_ptk_info tpi;
 	bool csum_err = false;
 
-	if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP)) < 0) {
+	if (gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP),
+			     iph->ihl * 4) < 0) {
 		if (!csum_err)		/* ignore csum errors. */
 			return;
 	}
@@ -338,7 +343,7 @@ static int gre_rcv(struct sk_buff *skb)
 	}
 #endif
 
-	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP));
+	hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0);
 	if (hdr_len < 0)
 		goto drop;
 
@@ -841,17 +846,19 @@ out:
 	return ipgre_tunnel_validate(tb, data);
 }
 
-static void ipgre_netlink_parms(struct net_device *dev,
+static int ipgre_netlink_parms(struct net_device *dev,
 				struct nlattr *data[],
 				struct nlattr *tb[],
 				struct ip_tunnel_parm *parms)
 {
+	struct ip_tunnel *t = netdev_priv(dev);
+
 	memset(parms, 0, sizeof(*parms));
 
 	parms->iph.protocol = IPPROTO_GRE;
 
 	if (!data)
-		return;
+		return 0;
 
 	if (data[IFLA_GRE_LINK])
 		parms->link = nla_get_u32(data[IFLA_GRE_LINK]);
@@ -880,16 +887,26 @@ static void ipgre_netlink_parms(struct net_device *dev,
 	if (data[IFLA_GRE_TOS])
 		parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]);
 
-	if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC]))
+	if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) {
+		if (t->ignore_df)
+			return -EINVAL;
 		parms->iph.frag_off = htons(IP_DF);
+	}
 
 	if (data[IFLA_GRE_COLLECT_METADATA]) {
-		struct ip_tunnel *t = netdev_priv(dev);
-
 		t->collect_md = true;
 		if (dev->type == ARPHRD_IPGRE)
 			dev->type = ARPHRD_NONE;
 	}
+
+	if (data[IFLA_GRE_IGNORE_DF]) {
+		if (nla_get_u8(data[IFLA_GRE_IGNORE_DF])
+		  && (parms->iph.frag_off & htons(IP_DF)))
+			return -EINVAL;
+		t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]);
+	}
+
+	return 0;
 }
 
 /* This function returns true when ENCAP attributes are present in the nl msg */
@@ -960,16 +977,19 @@ static int ipgre_newlink(struct net *src_net, struct net_device *dev,
 {
 	struct ip_tunnel_parm p;
 	struct ip_tunnel_encap ipencap;
+	int err;
 
 	if (ipgre_netlink_encap_parms(data, &ipencap)) {
 		struct ip_tunnel *t = netdev_priv(dev);
-		int err = ip_tunnel_encap_setup(t, &ipencap);
+		err = ip_tunnel_encap_setup(t, &ipencap);
 
 		if (err < 0)
 			return err;
 	}
 
-	ipgre_netlink_parms(dev, data, tb, &p);
+	err = ipgre_netlink_parms(dev, data, tb, &p);
+	if (err < 0)
+		return err;
 	return ip_tunnel_newlink(dev, tb, &p);
 }
 
@@ -978,16 +998,19 @@ static int ipgre_changelink(struct net_device *dev, struct nlattr *tb[],
 {
 	struct ip_tunnel_parm p;
 	struct ip_tunnel_encap ipencap;
+	int err;
 
 	if (ipgre_netlink_encap_parms(data, &ipencap)) {
 		struct ip_tunnel *t = netdev_priv(dev);
-		int err = ip_tunnel_encap_setup(t, &ipencap);
+		err = ip_tunnel_encap_setup(t, &ipencap);
 
 		if (err < 0)
 			return err;
 	}
 
-	ipgre_netlink_parms(dev, data, tb, &p);
+	err = ipgre_netlink_parms(dev, data, tb, &p);
+	if (err < 0)
+		return err;
 	return ip_tunnel_changelink(dev, tb, &p);
 }
 
@@ -1024,6 +1047,8 @@ static size_t ipgre_get_size(const struct net_device *dev)
 		nla_total_size(2) +
 		/* IFLA_GRE_COLLECT_METADATA */
 		nla_total_size(0) +
+		/* IFLA_GRE_IGNORE_DF */
+		nla_total_size(1) +
 		0;
 }
 
@@ -1057,6 +1082,9 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
 			t->encap.flags))
 		goto nla_put_failure;
 
+	if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df))
+		goto nla_put_failure;
+
 	if (t->collect_md) {
 		if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
 			goto nla_put_failure;
@@ -1084,6 +1112,7 @@ static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
 	[IFLA_GRE_ENCAP_SPORT]	= { .type = NLA_U16 },
 	[IFLA_GRE_ENCAP_DPORT]	= { .type = NLA_U16 },
 	[IFLA_GRE_COLLECT_METADATA]	= { .type = NLA_FLAG },
+	[IFLA_GRE_IGNORE_DF]	= { .type = NLA_U8 },
 };
 
 static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
@@ -1121,6 +1150,7 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 {
 	struct nlattr *tb[IFLA_MAX + 1];
 	struct net_device *dev;
+	LIST_HEAD(list_kill);
 	struct ip_tunnel *t;
 	int err;
 
@@ -1136,8 +1166,10 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 	t->collect_md = true;
 
 	err = ipgre_newlink(net, dev, tb, NULL);
-	if (err < 0)
-		goto out;
+	if (err < 0) {
+		free_netdev(dev);
+		return ERR_PTR(err);
+	}
 
 	/* openvswitch users expect packet sizes to be unrestricted,
 	 * so set the largest MTU we can.
@@ -1146,9 +1178,14 @@ struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
 	if (err)
 		goto out;
 
+	err = rtnl_configure_link(dev, NULL);
+	if (err < 0)
+		goto out;
+
 	return dev;
 out:
-	free_netdev(dev);
+	ip_tunnel_dellink(dev, &list_kill);
+	unregister_netdevice_many(&list_kill);
 	return ERR_PTR(err);
 }
 EXPORT_SYMBOL_GPL(gretap_fb_dev_create);