1 files changed, 186 insertions, 43 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 6602a2e9cdb5..794c13674e8a 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -46,6 +46,7 @@
 #include <net/tcp_states.h>
 #include <net/ip6_checksum.h>
 #include <net/ip6_tunnel.h>
+#include <net/udp_tunnel.h>
 #include <net/xfrm.h>
 #include <net/inet_hashtables.h>
 #include <net/inet6_hashtables.h>
@@ -66,10 +67,11 @@ static void udpv6_destruct_sock(struct sock *sk)
 
 int udpv6_init_sock(struct sock *sk)
 {
-	udp_lib_init_sock(sk);
+	int res = udp_lib_init_sock(sk);
+
 	sk->sk_destruct = udpv6_destruct_sock;
 	set_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags);
-	return 0;
+	return res;
 }
 
 INDIRECT_CALLABLE_SCOPE
@@ -110,11 +112,22 @@ void udp_v6_rehash(struct sock *sk)
 	u16 new_hash = ipv6_portaddr_hash(sock_net(sk),
 					  &sk->sk_v6_rcv_saddr,
 					  inet_sk(sk)->inet_num);
+	u16 new_hash4;
+
+	if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) {
+		new_hash4 = udp_ehashfn(sock_net(sk),
+					sk->sk_rcv_saddr, sk->sk_num,
+					sk->sk_daddr, sk->sk_dport);
+	} else {
+		new_hash4 = udp6_ehashfn(sock_net(sk),
+					 &sk->sk_v6_rcv_saddr, sk->sk_num,
+					 &sk->sk_v6_daddr, sk->sk_dport);
+	}
 
-	udp_lib_rehash(sk, new_hash);
+	udp_lib_rehash(sk, new_hash, new_hash4);
 }
 
-static int compute_score(struct sock *sk, struct net *net,
+static int compute_score(struct sock *sk, const struct net *net,
 			 const struct in6_addr *saddr, __be16 sport,
 			 const struct in6_addr *daddr, unsigned short hnum,
 			 int dif, int sdif)
@@ -159,8 +172,51 @@ static int compute_score(struct sock *sk, struct net *net,
 	return score;
 }
 
+/**
+ * udp6_lib_lookup1() - Simplified lookup using primary hash (destination port)
+ * @net:	Network namespace
+ * @saddr:	Source address, network order
+ * @sport:	Source port, network order
+ * @daddr:	Destination address, network order
+ * @hnum:	Destination port, host order
+ * @dif:	Destination interface index
+ * @sdif:	Destination bridge port index, if relevant
+ * @udptable:	Set of UDP hash tables
+ *
+ * Simplified lookup to be used as fallback if no sockets are found due to a
+ * potential race between (receive) address change, and lookup happening before
+ * the rehash operation. This function ignores SO_REUSEPORT groups while scoring
+ * result sockets, because if we have one, we don't need the fallback at all.
+ *
+ * Called under rcu_read_lock().
+ *
+ * Return: socket with highest matching score if any, NULL if none
+ */
+static struct sock *udp6_lib_lookup1(const struct net *net,
+				     const struct in6_addr *saddr, __be16 sport,
+				     const struct in6_addr *daddr,
+				     unsigned int hnum, int dif, int sdif,
+				     const struct udp_table *udptable)
+{
+	unsigned int slot = udp_hashfn(net, hnum, udptable->mask);
+	struct udp_hslot *hslot = &udptable->hash[slot];
+	struct sock *sk, *result = NULL;
+	int score, badness = 0;
+
+	sk_for_each_rcu(sk, &hslot->head) {
+		score = compute_score(sk, net,
+				      saddr, sport, daddr, hnum, dif, sdif);
+		if (score > badness) {
+			result = sk;
+			badness = score;
+		}
+	}
+
+	return result;
+}
+
 /* called with rcu_read_lock() */
-static struct sock *udp6_lib_lookup2(struct net *net,
+static struct sock *udp6_lib_lookup2(const struct net *net,
 		const struct in6_addr *saddr, __be16 sport,
 		const struct in6_addr *daddr, unsigned int hnum,
 		int dif, int sdif, struct udp_hslot *hslot2,
@@ -205,7 +261,7 @@ rescore:
 
 			/* compute_score is too long of a function to be
 			 * inlined, and calling it again here yields
-			 * measureable overhead for some
+			 * measurable overhead for some
 			 * workloads. Work around it by jumping
 			 * backwards to rescore 'result'.
 			 */
@@ -216,21 +272,95 @@ rescore:
 	return result;
 }
 
+#if IS_ENABLED(CONFIG_BASE_SMALL)
+static struct sock *udp6_lib_lookup4(const struct net *net,
+				     const struct in6_addr *saddr, __be16 sport,
+				     const struct in6_addr *daddr,
+				     unsigned int hnum, int dif, int sdif,
+				     struct udp_table *udptable)
+{
+	return NULL;
+}
+
+static void udp6_hash4(struct sock *sk)
+{
+}
+#else /* !CONFIG_BASE_SMALL */
+static struct sock *udp6_lib_lookup4(const struct net *net,
+				     const struct in6_addr *saddr, __be16 sport,
+				     const struct in6_addr *daddr,
+				     unsigned int hnum, int dif, int sdif,
+				     struct udp_table *udptable)
+{
+	const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
+	const struct hlist_nulls_node *node;
+	struct udp_hslot *hslot4;
+	unsigned int hash4, slot;
+	struct udp_sock *up;
+	struct sock *sk;
+
+	hash4 = udp6_ehashfn(net, daddr, hnum, saddr, sport);
+	slot = hash4 & udptable->mask;
+	hslot4 = &udptable->hash4[slot];
+
+begin:
+	udp_lrpa_for_each_entry_rcu(up, node, &hslot4->nulls_head) {
+		sk = (struct sock *)up;
+		if (inet6_match(net, sk, saddr, daddr, ports, dif, sdif))
+			return sk;
+	}
+
+	/* if the nulls value we got at the end of this lookup is not the
+	 * expected one, we must restart lookup. We probably met an item that
+	 * was moved to another chain due to rehash.
+	 */
+	if (get_nulls_value(node) != slot)
+		goto begin;
+
+	return NULL;
+}
+
+static void udp6_hash4(struct sock *sk)
+{
+	struct net *net = sock_net(sk);
+	unsigned int hash;
+
+	if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) {
+		udp4_hash4(sk);
+		return;
+	}
+
+	if (sk_unhashed(sk) || ipv6_addr_any(&sk->sk_v6_rcv_saddr))
+		return;
+
+	hash = udp6_ehashfn(net, &sk->sk_v6_rcv_saddr, sk->sk_num,
+			    &sk->sk_v6_daddr, sk->sk_dport);
+
+	udp_lib_hash4(sk, hash);
+}
+#endif /* CONFIG_BASE_SMALL */
+
 /* rcu_read_lock() must be held */
-struct sock *__udp6_lib_lookup(struct net *net,
+struct sock *__udp6_lib_lookup(const struct net *net,
 			       const struct in6_addr *saddr, __be16 sport,
 			       const struct in6_addr *daddr, __be16 dport,
 			       int dif, int sdif, struct udp_table *udptable,
 			       struct sk_buff *skb)
 {
 	unsigned short hnum = ntohs(dport);
-	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
 	struct sock *result, *sk;
+	unsigned int hash2;
 
 	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
+
+	if (udp_has_hash4(hslot2)) {
+		result = udp6_lib_lookup4(net, saddr, sport, daddr, hnum,
+					  dif, sdif, udptable);
+		if (result) /* udp6_lib_lookup4 return sk or NULL */
+			return result;
+	}
 
 	/* Lookup connected or non-wildcard sockets */
 	result = udp6_lib_lookup2(net, saddr, sport,
@@ -257,12 +387,18 @@ struct sock *__udp6_lib_lookup(struct net *net,
 
 	/* Lookup wildcard sockets */
 	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 
 	result = udp6_lib_lookup2(net, saddr, sport,
 				  &in6addr_any, hnum, dif, sdif,
 				  hslot2, skb);
+	if (!IS_ERR_OR_NULL(result))
+		goto done;
+
+	/* Cover address change/lookup/rehash race: see __udp4_lib_lookup() */
+	result = udp6_lib_lookup1(net, saddr, sport, daddr, hnum, dif, sdif,
+				  udptable);
+
 done:
 	if (IS_ERR(result))
 		return NULL;
@@ -300,7 +436,7 @@ struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
  * Does increment socket refcount.
  */
 #if IS_ENABLED(CONFIG_NF_TPROXY_IPV6) || IS_ENABLED(CONFIG_NF_SOCKET_IPV6)
-struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be16 sport,
+struct sock *udp6_lib_lookup(const struct net *net, const struct in6_addr *saddr, __be16 sport,
 			     const struct in6_addr *daddr, __be16 dport, int dif)
 {
 	struct sock *sk;
@@ -314,7 +450,7 @@ struct sock *udp6_lib_lookup(struct net *net, const struct in6_addr *saddr, __be
 EXPORT_SYMBOL_GPL(udp6_lib_lookup);
 #endif
 
-/* do not use the scratch area len for jumbogram: their length execeeds the
+/* do not use the scratch area len for jumbogram: their length exceeds the
  * scratch area space; note that the IP6CB flags is still in the first
  * cacheline, so checking for jumbograms is cheap
  */
@@ -344,7 +480,7 @@ int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	if (flags & MSG_ERRQUEUE)
 		return ipv6_recv_error(sk, msg, len, addr_len);
 
-	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
+	if (np->rxopt.bits.rxpmtu && READ_ONCE(np->rxpmtu))
 		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
 
 try_again:
@@ -389,7 +525,7 @@ try_again:
 	}
 	if (unlikely(err)) {
 		if (!peeking) {
-			atomic_inc(&sk->sk_drops);
+			udp_drops_inc(sk);
 			SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 		}
 		kfree_skb(skb);
@@ -452,7 +588,7 @@ csum_copy_err:
 		SNMP_INC_STATS(mib, UDP_MIB_CSUMERRORS);
 		SNMP_INC_STATS(mib, UDP_MIB_INERRORS);
 	}
-	kfree_skb(skb);
+	kfree_skb_reason(skb, SKB_DROP_REASON_UDP_CSUM);
 
 	/* starting over for a new packet, but check if we need to yield */
 	cond_resched();
@@ -615,7 +751,8 @@ int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
 	if (type == NDISC_REDIRECT) {
 		if (tunnel) {
 			ip6_redirect(skb, sock_net(sk), inet6_iif(skb),
-				     READ_ONCE(sk->sk_mark), sk->sk_uid);
+				     READ_ONCE(sk->sk_mark),
+				     sk_uid(sk));
 		} else {
 			ip6_sk_redirect(skb, sk);
 		}
@@ -758,10 +895,8 @@ static int udpv6_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
 	    udp_lib_checksum_complete(skb))
 		goto csum_error;
 
-	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) {
-		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
+	if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr), &drop_reason))
 		goto drop;
-	}
 
 	udp_csum_pull_header(skb);
 
@@ -774,7 +909,7 @@ csum_error:
 	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
 drop:
 	__UDP6_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
-	atomic_inc(&sk->sk_drops);
+	udp_drops_inc(sk);
 	sk_skb_reason_drop(sk, skb, drop_reason);
 	return -1;
 }
@@ -859,7 +994,7 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 			    udptable->mask;
 		hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 start_lookup:
-		hslot = &udptable->hash2[hash2];
+		hslot = &udptable->hash2[hash2].hslot;
 		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 	}
 
@@ -879,7 +1014,7 @@ start_lookup:
 		}
 		nskb = skb_clone(skb, GFP_ATOMIC);
 		if (unlikely(!nskb)) {
-			atomic_inc(&sk->sk_drops);
+			udp_drops_inc(sk);
 			__UDP6_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
 					 IS_UDPLITE(sk));
 			__UDP6_INC_STATS(net, UDP_MIB_INERRORS,
@@ -914,7 +1049,7 @@ static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
 		sk->sk_rx_dst_cookie = rt6_get_cookie(dst_rt6_info(dst));
 }
 
-/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
+/* wrapper for udp_queue_rcv_skb taking care of csum conversion and
  * return code conversion for ip layer consumption
  */
 static int udp6_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
@@ -1065,14 +1200,13 @@ static struct sock *__udp6_lib_demux_lookup(struct net *net,
 {
 	struct udp_table *udptable = net->ipv4.udp_table;
 	unsigned short hnum = ntohs(loc_port);
-	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
+	unsigned int hash2;
 	__portpair ports;
 	struct sock *sk;
 
 	hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 	ports = INET_COMBINED_PORTS(rmt_port, hnum);
 
 	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
@@ -1148,7 +1282,7 @@ static void udp_v6_flush_pending_frames(struct sock *sk)
 	}
 }
 
-static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
+static int udpv6_pre_connect(struct sock *sk, struct sockaddr_unsized *uaddr,
 			     int addr_len)
 {
 	if (addr_len < offsetofend(struct sockaddr, sa_family))
@@ -1169,6 +1303,19 @@ static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
 	return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr, &addr_len);
 }
 
+static int udpv6_connect(struct sock *sk, struct sockaddr_unsized *uaddr,
+			 int addr_len)
+{
+	int res;
+
+	lock_sock(sk);
+	res = __ip6_datagram_connect(sk, uaddr, addr_len);
+	if (!res)
+		udp6_hash4(sk);
+	release_sock(sk);
+	return res;
+}
+
 /**
  *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming
  *	@sk:	socket we are sending on
@@ -1244,9 +1391,9 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
 		const int hlen = skb_network_header_len(skb) +
 				 sizeof(struct udphdr);
 
-		if (hlen + cork->gso_size > cork->fragsize) {
+		if (hlen + min(datalen, cork->gso_size) > cork->fragsize) {
 			kfree_skb(skb);
-			return -EINVAL;
+			return -EMSGSIZE;
 		}
 		if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) {
 			kfree_skb(skb);
@@ -1266,8 +1413,10 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
 			skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
 			skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
 								 cork->gso_size);
+
+			/* Don't checksum the payload, skb will get segmented */
+			goto csum_partial;
 		}
-		goto csum_partial;
 	}
 
 	if (is_udplite)
@@ -1347,10 +1496,8 @@ int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 	int is_udplite = IS_UDPLITE(sk);
 	int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
 
-	ipcm6_init(&ipc6);
+	ipcm6_init_sk(&ipc6, sk);
 	ipc6.gso_size = READ_ONCE(up->gso_size);
-	ipc6.sockc.tsflags = READ_ONCE(sk->sk_tsflags);
-	ipc6.sockc.mark = READ_ONCE(sk->sk_mark);
 
 	/* destination address check */
 	if (sin6) {
@@ -1474,7 +1621,7 @@ do_udp_sendmsg:
 	if (!fl6->flowi6_oif)
 		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
 
-	fl6->flowi6_uid = sk->sk_uid;
+	fl6->flowi6_uid = sk_uid(sk);
 
 	if (msg->msg_controllen) {
 		opt = &opt_space;
@@ -1556,9 +1703,6 @@ do_udp_sendmsg:
 
 	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 
-	if (ipc6.tclass < 0)
-		ipc6.tclass = np->tclass;
-
 	fl6->flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6->flowlabel);
 
 	dst = ip6_sk_dst_lookup_flow(sk, fl6, final_p, connected);
@@ -1604,8 +1748,6 @@ back_from_confirm:
 	WRITE_ONCE(up->pending, AF_INET6);
 
 do_append_data:
-	if (ipc6.dontfrag < 0)
-		ipc6.dontfrag = inet6_test_bit(DONTFRAG, sk);
 	up->len += ulen;
 	err = ip6_append_data(sk, getfrag, msg, ulen, sizeof(struct udphdr),
 			      &ipc6, fl6, dst_rt6_info(dst),
@@ -1685,6 +1827,7 @@ void udpv6_destroy_sock(struct sock *sk)
 		if (udp_test_bit(ENCAP_ENABLED, sk)) {
 			static_branch_dec(&udpv6_encap_needed_key);
 			udp_encap_disable();
+			udp_tunnel_cleanup_gro(sk);
 		}
 	}
 }
@@ -1762,7 +1905,7 @@ struct proto udpv6_prot = {
 	.owner			= THIS_MODULE,
 	.close			= udp_lib_close,
 	.pre_connect		= udpv6_pre_connect,
-	.connect		= ip6_datagram_connect,
+	.connect		= udpv6_connect,
 	.disconnect		= udp_disconnect,
 	.ioctl			= udp_ioctl,
 	.init			= udpv6_init_sock,
@@ -1782,7 +1925,7 @@ struct proto udpv6_prot = {
 	.psock_update_sk_prot	= udp_bpf_update_proto,
 #endif
 
-	.memory_allocated	= &udp_memory_allocated,
+	.memory_allocated	= &net_aligned_data.udp_memory_allocated,
 	.per_cpu_fw_alloc	= &udp_memory_per_cpu_fw_alloc,
 
 	.sysctl_mem		= sysctl_udp_mem,