Merge branch 'inet-ping-misc-changes'

Eric Dumazet says:

====================
inet: ping: misc changes

First and third patches improve security a bit.

Second patch (ping_hash removal) is a cleanup.

Fourth patch uses EXPORT_IPV6_MOD[_GPL].
====================

Link: https://patch.msgid.link/20250829153054.474201-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

include/net/netns/ipv4.h

@@ -251,6 +251,7 @@ struct netns_ipv4 {
 	int sysctl_igmp_qrv;
 
 	struct ping_group_range ping_group_range;
+	u16			ping_port_rover;
 
 	atomic_t dev_addr_genid;
 

include/net/ping.h

@@ -54,7 +54,6 @@ struct pingfakehdr {
 };
 
 int  ping_get_port(struct sock *sk, unsigned short ident);
-int ping_hash(struct sock *sk);
 void ping_unhash(struct sock *sk);
 
 int  ping_init_sock(struct sock *sk);

net/ipv4/ping.c

@@ -56,9 +56,7 @@ struct ping_table {
 
 static struct ping_table ping_table;
 struct pingv6_ops pingv6_ops;
-EXPORT_SYMBOL_GPL(pingv6_ops);
-
-static u16 ping_port_rover;
+EXPORT_IPV6_MOD_GPL(pingv6_ops);
 
 static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
 {
@@ -67,7 +65,6 @@ static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
 	pr_debug("hash(%u) = %u\n", num, res);
 	return res;
 }
-EXPORT_SYMBOL_GPL(ping_hash);
 
 static inline struct hlist_head *ping_hashslot(struct ping_table *table,
 					       struct net *net, unsigned int num)
@@ -77,6 +74,7 @@ static inline struct hlist_head *ping_hashslot(struct ping_table *table,
 
 int ping_get_port(struct sock *sk, unsigned short ident)
 {
+	struct net *net = sock_net(sk);
 	struct inet_sock *isk, *isk2;
 	struct hlist_head *hlist;
 	struct sock *sk2 = NULL;
@@ -84,15 +82,16 @@ int ping_get_port(struct sock *sk, unsigned short ident)
 	isk = inet_sk(sk);
 	spin_lock(&ping_table.lock);
 	if (ident == 0) {
+		u16 result = net->ipv4.ping_port_rover + 1;
 		u32 i;
-		u16 result = ping_port_rover + 1;
 
 		for (i = 0; i < (1L << 16); i++, result++) {
 			if (!result)
-				result++; /* avoid zero */
-			hlist = ping_hashslot(&ping_table, sock_net(sk),
-					    result);
+				continue; /* avoid zero */
+			hlist = ping_hashslot(&ping_table, net, result);
 			sk_for_each(sk2, hlist) {
+				if (!net_eq(sock_net(sk2), net))
+					continue;
 				isk2 = inet_sk(sk2);
 
 				if (isk2->inet_num == result)
@@ -100,7 +99,7 @@ int ping_get_port(struct sock *sk, unsigned short ident)
 			}
 
 			/* found */
-			ping_port_rover = ident = result;
+			net->ipv4.ping_port_rover = ident = result;
 			break;
 next_port:
 			;
@@ -108,8 +107,10 @@ next_port:
 		if (i >= (1L << 16))
 			goto fail;
 	} else {
-		hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
+		hlist = ping_hashslot(&ping_table, net, ident);
 		sk_for_each(sk2, hlist) {
+			if (!net_eq(sock_net(sk2), net))
+				continue;
 			isk2 = inet_sk(sk2);
 
 			/* BUG? Why is this reuse and not reuseaddr? ping.c
@@ -129,7 +130,7 @@ next_port:
 		pr_debug("was not hashed\n");
 		sk_add_node_rcu(sk, hlist);
 		sock_set_flag(sk, SOCK_RCU_FREE);
-		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+		sock_prot_inuse_add(net, sk->sk_prot, 1);
 	}
 	spin_unlock(&ping_table.lock);
 	return 0;
@@ -138,15 +139,7 @@ fail:
 	spin_unlock(&ping_table.lock);
 	return -EADDRINUSE;
 }
-EXPORT_SYMBOL_GPL(ping_get_port);
-
-int ping_hash(struct sock *sk)
-{
-	pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
-	BUG(); /* "Please do not press this button again." */
-
-	return 0;
-}
+EXPORT_IPV6_MOD_GPL(ping_get_port);
 
 void ping_unhash(struct sock *sk)
 {
@@ -161,7 +154,7 @@ void ping_unhash(struct sock *sk)
 	}
 	spin_unlock(&ping_table.lock);
 }
-EXPORT_SYMBOL_GPL(ping_unhash);
+EXPORT_IPV6_MOD_GPL(ping_unhash);
 
 /* Called under rcu_read_lock() */
 static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
@@ -188,6 +181,8 @@ static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
 	}
 
 	sk_for_each_rcu(sk, hslot) {
+		if (!net_eq(sock_net(sk), net))
+			continue;
 		isk = inet_sk(sk);
 
 		pr_debug("iterate\n");
@@ -279,7 +274,7 @@ out_release_group:
 	put_group_info(group_info);
 	return ret;
 }
-EXPORT_SYMBOL_GPL(ping_init_sock);
+EXPORT_IPV6_MOD_GPL(ping_init_sock);
 
 void ping_close(struct sock *sk, long timeout)
 {
@@ -289,7 +284,7 @@ void ping_close(struct sock *sk, long timeout)
 
 	sk_common_release(sk);
 }
-EXPORT_SYMBOL_GPL(ping_close);
+EXPORT_IPV6_MOD_GPL(ping_close);
 
 static int ping_pre_connect(struct sock *sk, struct sockaddr *uaddr,
 			    int addr_len)
@@ -467,7 +462,7 @@ out:
 	pr_debug("ping_v4_bind -> %d\n", err);
 	return err;
 }
-EXPORT_SYMBOL_GPL(ping_bind);
+EXPORT_IPV6_MOD_GPL(ping_bind);
 
 /*
  * Is this a supported type of ICMP message?
@@ -600,7 +595,7 @@ void ping_err(struct sk_buff *skb, int offset, u32 info)
 out:
 	return;
 }
-EXPORT_SYMBOL_GPL(ping_err);
+EXPORT_IPV6_MOD_GPL(ping_err);
 
 /*
  *	Copy and checksum an ICMP Echo packet from user space into a buffer
@@ -630,7 +625,7 @@ int ping_getfrag(void *from, char *to,
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(ping_getfrag);
+EXPORT_IPV6_MOD_GPL(ping_getfrag);
 
 static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
 				       struct flowi4 *fl4)
@@ -691,7 +686,7 @@ int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(ping_common_sendmsg);
+EXPORT_IPV6_MOD_GPL(ping_common_sendmsg);
 
 static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 {
@@ -936,7 +931,7 @@ out:
 	pr_debug("ping_recvmsg -> %d\n", err);
 	return err;
 }
-EXPORT_SYMBOL_GPL(ping_recvmsg);
+EXPORT_IPV6_MOD_GPL(ping_recvmsg);
 
 static enum skb_drop_reason __ping_queue_rcv_skb(struct sock *sk,
 						 struct sk_buff *skb)
@@ -957,7 +952,7 @@ int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
 	return __ping_queue_rcv_skb(sk, skb) ? -1 : 0;
 }
-EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
+EXPORT_IPV6_MOD_GPL(ping_queue_rcv_skb);
 
 
 /*
@@ -985,7 +980,7 @@ enum skb_drop_reason ping_rcv(struct sk_buff *skb)
 	kfree_skb_reason(skb, SKB_DROP_REASON_NO_SOCKET);
 	return SKB_DROP_REASON_NO_SOCKET;
 }
-EXPORT_SYMBOL_GPL(ping_rcv);
+EXPORT_IPV6_MOD_GPL(ping_rcv);
 
 struct proto ping_prot = {
 	.name =		"PING",
@@ -1002,13 +997,12 @@ struct proto ping_prot = {
 	.bind =		ping_bind,
 	.backlog_rcv =	ping_queue_rcv_skb,
 	.release_cb =	ip4_datagram_release_cb,
-	.hash =		ping_hash,
 	.unhash =	ping_unhash,
 	.get_port =	ping_get_port,
 	.put_port =	ping_unhash,
 	.obj_size =	sizeof(struct inet_sock),
 };
-EXPORT_SYMBOL(ping_prot);
+EXPORT_IPV6_MOD(ping_prot);
 
 #ifdef CONFIG_PROC_FS
 
@@ -1073,7 +1067,7 @@ void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
 
 	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
 }
-EXPORT_SYMBOL_GPL(ping_seq_start);
+EXPORT_IPV6_MOD_GPL(ping_seq_start);
 
 static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
 {
@@ -1092,14 +1086,14 @@ void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 	++*pos;
 	return sk;
 }
-EXPORT_SYMBOL_GPL(ping_seq_next);
+EXPORT_IPV6_MOD_GPL(ping_seq_next);
 
 void ping_seq_stop(struct seq_file *seq, void *v)
 	__releases(ping_table.lock)
 {
 	spin_unlock(&ping_table.lock);
 }
-EXPORT_SYMBOL_GPL(ping_seq_stop);
+EXPORT_IPV6_MOD_GPL(ping_seq_stop);
 
 static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
 		int bucket)
@@ -1150,6 +1144,8 @@ static int __net_init ping_v4_proc_init_net(struct net *net)
 	if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops,
 			sizeof(struct ping_iter_state)))
 		return -ENOMEM;
+
+	net->ipv4.ping_port_rover = get_random_u16();
 	return 0;
 }
 

net/ipv6/ping.c

@@ -208,7 +208,6 @@ struct proto pingv6_prot = {
 	.recvmsg =	ping_recvmsg,
 	.bind =		ping_bind,
 	.backlog_rcv =	ping_queue_rcv_skb,
-	.hash =		ping_hash,
 	.unhash =	ping_unhash,
 	.get_port =	ping_get_port,
 	.put_port =	ping_unhash,