1 files changed, 53 insertions, 64 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 8aab7d78d25b..ea6e4cff9faf 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -134,14 +134,21 @@ EXPORT_SYMBOL(udp_memory_allocated);
 #define MAX_UDP_PORTS 65536
 #define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
 
+/* IPCB reference means this can not be used from early demux */
+static bool udp_lib_exact_dif_match(struct net *net, struct sk_buff *skb)
+{
+#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
+	if (!net->ipv4.sysctl_udp_l3mdev_accept &&
+	    skb && ipv4_l3mdev_skb(IPCB(skb)->flags))
+		return true;
+#endif
+	return false;
+}
+
 static int udp_lib_lport_inuse(struct net *net, __u16 num,
 			       const struct udp_hslot *hslot,
 			       unsigned long *bitmap,
-			       struct sock *sk,
-			       int (*saddr_comp)(const struct sock *sk1,
-						 const struct sock *sk2,
-						 bool match_wildcard),
-			       unsigned int log)
+			       struct sock *sk, unsigned int log)
 {
 	struct sock *sk2;
 	kuid_t uid = sock_i_uid(sk);
@@ -153,13 +160,18 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num,
 		    (!sk2->sk_reuse || !sk->sk_reuse) &&
 		    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
 		     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
-		    (!sk2->sk_reuseport || !sk->sk_reuseport ||
-		     rcu_access_pointer(sk->sk_reuseport_cb) ||
-		     !uid_eq(uid, sock_i_uid(sk2))) &&
-		    saddr_comp(sk, sk2, true)) {
-			if (!bitmap)
-				return 1;
-			__set_bit(udp_sk(sk2)->udp_port_hash >> log, bitmap);
+		    inet_rcv_saddr_equal(sk, sk2, true)) {
+			if (sk2->sk_reuseport && sk->sk_reuseport &&
+			    !rcu_access_pointer(sk->sk_reuseport_cb) &&
+			    uid_eq(uid, sock_i_uid(sk2))) {
+				if (!bitmap)
+					return 0;
+			} else {
+				if (!bitmap)
+					return 1;
+				__set_bit(udp_sk(sk2)->udp_port_hash >> log,
+					  bitmap);
+			}
 		}
 	}
 	return 0;
@@ -171,10 +183,7 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num,
  */
 static int udp_lib_lport_inuse2(struct net *net, __u16 num,
 				struct udp_hslot *hslot2,
-				struct sock *sk,
-				int (*saddr_comp)(const struct sock *sk1,
-						  const struct sock *sk2,
-						  bool match_wildcard))
+				struct sock *sk)
 {
 	struct sock *sk2;
 	kuid_t uid = sock_i_uid(sk);
@@ -188,11 +197,14 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num,
 		    (!sk2->sk_reuse || !sk->sk_reuse) &&
 		    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
 		     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
-		    (!sk2->sk_reuseport || !sk->sk_reuseport ||
-		     rcu_access_pointer(sk->sk_reuseport_cb) ||
-		     !uid_eq(uid, sock_i_uid(sk2))) &&
-		    saddr_comp(sk, sk2, true)) {
-			res = 1;
+		    inet_rcv_saddr_equal(sk, sk2, true)) {
+			if (sk2->sk_reuseport && sk->sk_reuseport &&
+			    !rcu_access_pointer(sk->sk_reuseport_cb) &&
+			    uid_eq(uid, sock_i_uid(sk2))) {
+				res = 0;
+			} else {
+				res = 1;
+			}
 			break;
 		}
 	}
@@ -200,10 +212,7 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num,
 	return res;
 }
 
-static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot,
-				  int (*saddr_same)(const struct sock *sk1,
-						    const struct sock *sk2,
-						    bool match_wildcard))
+static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot)
 {
 	struct net *net = sock_net(sk);
 	kuid_t uid = sock_i_uid(sk);
@@ -217,7 +226,7 @@ static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot,
 		    (udp_sk(sk2)->udp_port_hash == udp_sk(sk)->udp_port_hash) &&
 		    (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 		    sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
-		    (*saddr_same)(sk, sk2, false)) {
+		    inet_rcv_saddr_equal(sk, sk2, false)) {
 			return reuseport_add_sock(sk, sk2);
 		}
 	}
@@ -233,14 +242,10 @@ static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot,
  *
  *  @sk:          socket struct in question
  *  @snum:        port number to look up
- *  @saddr_comp:  AF-dependent comparison of bound local IP addresses
  *  @hash2_nulladdr: AF-dependent hash value in secondary hash chains,
  *                   with NULL address
  */
 int udp_lib_get_port(struct sock *sk, unsigned short snum,
-		     int (*saddr_comp)(const struct sock *sk1,
-				       const struct sock *sk2,
-				       bool match_wildcard),
 		     unsigned int hash2_nulladdr)
 {
 	struct udp_hslot *hslot, *hslot2;
@@ -269,7 +274,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
 			bitmap_zero(bitmap, PORTS_PER_CHAIN);
 			spin_lock_bh(&hslot->lock);
 			udp_lib_lport_inuse(net, snum, hslot, bitmap, sk,
-					    saddr_comp, udptable->log);
+					    udptable->log);
 
 			snum = first;
 			/*
@@ -285,6 +290,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
 				snum += rand;
 			} while (snum != first);
 			spin_unlock_bh(&hslot->lock);
+			cond_resched();
 		} while (++first != last);
 		goto fail;
 	} else {
@@ -301,12 +307,11 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
 			if (hslot->count < hslot2->count)
 				goto scan_primary_hash;
 
-			exist = udp_lib_lport_inuse2(net, snum, hslot2,
-						     sk, saddr_comp);
+			exist = udp_lib_lport_inuse2(net, snum, hslot2, sk);
 			if (!exist && (hash2_nulladdr != slot2)) {
 				hslot2 = udp_hashslot2(udptable, hash2_nulladdr);
 				exist = udp_lib_lport_inuse2(net, snum, hslot2,
-							     sk, saddr_comp);
+							     sk);
 			}
 			if (exist)
 				goto fail_unlock;
@@ -314,8 +319,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
 				goto found;
 		}
 scan_primary_hash:
-		if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk,
-					saddr_comp, 0))
+		if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, 0))
 			goto fail_unlock;
 	}
 found:
@@ -324,7 +328,7 @@ found:
 	udp_sk(sk)->udp_portaddr_hash ^= snum;
 	if (sk_unhashed(sk)) {
 		if (sk->sk_reuseport &&
-		    udp_reuseport_add_sock(sk, hslot, saddr_comp)) {
+		    udp_reuseport_add_sock(sk, hslot)) {
 			inet_sk(sk)->inet_num = 0;
 			udp_sk(sk)->udp_port_hash = 0;
 			udp_sk(sk)->udp_portaddr_hash ^= snum;
@@ -356,24 +360,6 @@ fail:
 }
 EXPORT_SYMBOL(udp_lib_get_port);
 
-/* match_wildcard == true:  0.0.0.0 equals to any IPv4 addresses
- * match_wildcard == false: addresses must be exactly the same, i.e.
- *                          0.0.0.0 only equals to 0.0.0.0
- */
-int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2,
-			 bool match_wildcard)
-{
-	struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2);
-
-	if (!ipv6_only_sock(sk2)) {
-		if (inet1->inet_rcv_saddr == inet2->inet_rcv_saddr)
-			return 1;
-		if (!inet1->inet_rcv_saddr || !inet2->inet_rcv_saddr)
-			return match_wildcard;
-	}
-	return 0;
-}
-
 static u32 udp4_portaddr_hash(const struct net *net, __be32 saddr,
 			      unsigned int port)
 {
@@ -389,12 +375,13 @@ int udp_v4_get_port(struct sock *sk, unsigned short snum)
 
 	/* precompute partial secondary hash */
 	udp_sk(sk)->udp_portaddr_hash = hash2_partial;
-	return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal, hash2_nulladdr);
+	return udp_lib_get_port(sk, snum, hash2_nulladdr);
 }
 
 static int compute_score(struct sock *sk, struct net *net,
 			 __be32 saddr, __be16 sport,
-			 __be32 daddr, unsigned short hnum, int dif)
+			 __be32 daddr, unsigned short hnum, int dif,
+			 bool exact_dif)
 {
 	int score;
 	struct inet_sock *inet;
@@ -425,7 +412,7 @@ static int compute_score(struct sock *sk, struct net *net,
 		score += 4;
 	}
 
-	if (sk->sk_bound_dev_if) {
+	if (sk->sk_bound_dev_if || exact_dif) {
 		if (sk->sk_bound_dev_if != dif)
 			return -1;
 		score += 4;
@@ -450,7 +437,7 @@ static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
 /* called with rcu_read_lock() */
 static struct sock *udp4_lib_lookup2(struct net *net,
 		__be32 saddr, __be16 sport,
-		__be32 daddr, unsigned int hnum, int dif,
+		__be32 daddr, unsigned int hnum, int dif, bool exact_dif,
 		struct udp_hslot *hslot2,
 		struct sk_buff *skb)
 {
@@ -462,7 +449,7 @@ static struct sock *udp4_lib_lookup2(struct net *net,
 	badness = 0;
 	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
 		score = compute_score(sk, net, saddr, sport,
-				      daddr, hnum, dif);
+				      daddr, hnum, dif, exact_dif);
 		if (score > badness) {
 			reuseport = sk->sk_reuseport;
 			if (reuseport) {
@@ -497,6 +484,7 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 	unsigned short hnum = ntohs(dport);
 	unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
 	struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
+	bool exact_dif = udp_lib_exact_dif_match(net, skb);
 	int score, badness, matches = 0, reuseport = 0;
 	u32 hash = 0;
 
@@ -509,7 +497,7 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 
 		result = udp4_lib_lookup2(net, saddr, sport,
 					  daddr, hnum, dif,
-					  hslot2, skb);
+					  exact_dif, hslot2, skb);
 		if (!result) {
 			unsigned int old_slot2 = slot2;
 			hash2 = udp4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
@@ -524,7 +512,7 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 
 			result = udp4_lib_lookup2(net, saddr, sport,
 						  daddr, hnum, dif,
-						  hslot2, skb);
+						  exact_dif, hslot2, skb);
 		}
 		return result;
 	}
@@ -533,7 +521,7 @@ begin:
 	badness = 0;
 	sk_for_each_rcu(sk, &hslot->head) {
 		score = compute_score(sk, net, saddr, sport,
-				      daddr, hnum, dif);
+				      daddr, hnum, dif, exact_dif);
 		if (score > badness) {
 			reuseport = sk->sk_reuseport;
 			if (reuseport) {
@@ -1113,7 +1101,8 @@ out:
 	return err;
 
 do_confirm:
-	dst_confirm(&rt->dst);
+	if (msg->msg_flags & MSG_PROBE)
+		dst_confirm_neigh(&rt->dst, &fl4->daddr);
 	if (!(msg->msg_flags&MSG_PROBE) || len)
 		goto back_from_confirm;
 	err = 0;