Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2022-03-09

1) Fix IPv6 PMTU discovery for xfrm interfaces.
From Lina Wang.

2) Revert failing for policies and states that are
configured with XFRMA_IF_ID 0. It broke a
user configuration. From Kai Lueke.

3) Fix a possible buffer overflow in the ESP output path.

4) Fix ESP GSO for tunnel and BEET mode on inter address
family tunnels.
====================

Signed-off-by: David S. Miller <[e-mail]>

include/linux/netdevice.h

···
 
 struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
 				  netdev_features_t features, bool tx_path);
+struct sk_buff *skb_eth_gso_segment(struct sk_buff *skb,
+				    netdev_features_t features, __be16 type);
 struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
 				    netdev_features_t features);
 

include/net/esp.h

···
 
 #include <linux/skbuff.h>
 
+#define ESP_SKB_FRAG_MAXSIZE (PAGE_SIZE << SKB_FRAG_PAGE_ORDER)
+
 struct ip_esp_hdr;
 
 static inline struct ip_esp_hdr *ip_esp_hdr(const struct sk_buff *skb)

net/core/gro.c

···
 EXPORT_SYMBOL(dev_remove_offload);
 
 /**
+ *	skb_eth_gso_segment - segmentation handler for ethernet protocols.
+ *	@skb: buffer to segment
+ *	@features: features for the output path (see dev->features)
+ *	@type: Ethernet Protocol ID
+ */
+struct sk_buff *skb_eth_gso_segment(struct sk_buff *skb,
+				    netdev_features_t features, __be16 type)
+{
+	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
+	struct packet_offload *ptype;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ptype, &offload_base, list) {
+		if (ptype->type == type && ptype->callbacks.gso_segment) {
+			segs = ptype->callbacks.gso_segment(skb, features);
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return segs;
+}
+EXPORT_SYMBOL(skb_eth_gso_segment);
+
+/**
  *	skb_mac_gso_segment - mac layer segmentation handler.
  *	@skb: buffer to segment
  *	@features: features for the output path (see dev->features)

net/ipv4/esp4.c

···
 	struct page *page;
 	struct sk_buff *trailer;
 	int tailen = esp->tailen;
+	unsigned int allocsz;
 
 	/* this is non-NULL only with TCP/UDP Encapsulation */
 	if (x->encap) {
···
 		if (err < 0)
 			return err;
 	}
+
+	allocsz = ALIGN(skb->data_len + tailen, L1_CACHE_BYTES);
+	if (allocsz > ESP_SKB_FRAG_MAXSIZE)
+		goto cow;
 
 	if (!skb_cloned(skb)) {
 		if (tailen <= skb_tailroom(skb)) {

net/ipv4/esp4_offload.c

···
 						struct sk_buff *skb,
 						netdev_features_t features)
 {
-	__skb_push(skb, skb->mac_len);
-	return skb_mac_gso_segment(skb, features);
+	return skb_eth_gso_segment(skb, features, htons(ETH_P_IP));
 }
 
 static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
···
 		if (proto == IPPROTO_TCP)
 			skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
 	}
+
+	if (proto == IPPROTO_IPV6)
+		skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
 
 	__skb_pull(skb, skb_transport_offset(skb));
 	ops = rcu_dereference(inet_offloads[proto]);

net/ipv6/esp6.c

···
 	struct page *page;
 	struct sk_buff *trailer;
 	int tailen = esp->tailen;
+	unsigned int allocsz;
 
 	if (x->encap) {
 		int err = esp6_output_encap(x, skb, esp);
···
 		if (err < 0)
 			return err;
 	}
+
+	allocsz = ALIGN(skb->data_len + tailen, L1_CACHE_BYTES);
+	if (allocsz > ESP_SKB_FRAG_MAXSIZE)
+		goto cow;
 
 	if (!skb_cloned(skb)) {
 		if (tailen <= skb_tailroom(skb)) {

net/ipv6/esp6_offload.c

···
 						struct sk_buff *skb,
 						netdev_features_t features)
 {
-	__skb_push(skb, skb->mac_len);
-	return skb_mac_gso_segment(skb, features);
+	return skb_eth_gso_segment(skb, features, htons(ETH_P_IPV6));
 }
 
 static struct sk_buff *xfrm6_transport_gso_segment(struct xfrm_state *x,
···
 		skb->transport_header +=
 			ipv6_skip_exthdr(skb, 0, &proto, &frag);
 	}
+
+	if (proto == IPPROTO_IPIP)
+		skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
 
 	__skb_pull(skb, skb_transport_offset(skb));
 	ops = rcu_dereference(inet6_offloads[proto]);

net/ipv6/xfrm6_output.c

···
 	return xfrm_output(sk, skb);
 }
 
+static int xfrm6_noneed_fragment(struct sk_buff *skb)
+{
+	struct frag_hdr *fh;
+	u8 prevhdr = ipv6_hdr(skb)->nexthdr;
+
+	if (prevhdr != NEXTHDR_FRAGMENT)
+		return 0;
+	fh = (struct frag_hdr *)(skb->data + sizeof(struct ipv6hdr));
+	if (fh->nexthdr == NEXTHDR_ESP || fh->nexthdr == NEXTHDR_AUTH)
+		return 1;
+	return 0;
+}
+
 static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
···
 		xfrm6_local_rxpmtu(skb, mtu);
 		kfree_skb(skb);
 		return -EMSGSIZE;
+	} else if (toobig && xfrm6_noneed_fragment(skb)) {
+		skb->ignore_df = 1;
+		goto skip_frag;
 	} else if (!skb->ignore_df && toobig && skb->sk) {
 		xfrm_local_error(skb, mtu);
 		kfree_skb(skb);

net/xfrm/xfrm_interface.c

···
 			if (mtu < IPV6_MIN_MTU)
 				mtu = IPV6_MIN_MTU;
 
-			icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+			if (skb->len > 1280)
+				icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+			else
+				goto xmit;
 		} else {
 			if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
 				goto xmit;

net/xfrm/xfrm_user.c

···
 
 	xfrm_smark_init(attrs, &x->props.smark);
 
-	if (attrs[XFRMA_IF_ID]) {
+	if (attrs[XFRMA_IF_ID])
 		x->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
-		if (!x->if_id) {
-			err = -EINVAL;
-			goto error;
-		}
-	}
 
 	err = __xfrm_init_state(x, false, attrs[XFRMA_OFFLOAD_DEV]);
 	if (err)
···
 
 	mark = xfrm_mark_get(attrs, &m);
 
-	if (attrs[XFRMA_IF_ID]) {
+	if (attrs[XFRMA_IF_ID])
 		if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
-		if (!if_id) {
-			err = -EINVAL;
-			goto out_noput;
-		}
-	}
 
 	if (p->info.seq) {
 		x = xfrm_find_acq_byseq(net, mark, p->info.seq);
···
 
 	xfrm_mark_get(attrs, &xp->mark);
 
-	if (attrs[XFRMA_IF_ID]) {
+	if (attrs[XFRMA_IF_ID])
 		xp->if_id = nla_get_u32(attrs[XFRMA_IF_ID]);
-		if (!xp->if_id) {
-			err = -EINVAL;
-			goto error;
-		}
-	}
 
 	return xp;
  error: