Merge tag 'rxrpc-next-20221116' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Fix oops and missing config conditionals

The patches that were pulled into net-next previously[1] had some issues
that this patchset fixes:

 (1) Fix missing IPV6 config conditionals.

 (2) Fix an oops caused by calling udpv6_sendmsg() directly on an AF_INET
     socket.

 (3) Fix the validation of network addresses on entry to socket functions
     so that we don't allow an AF_INET6 address if we've selected an
     AF_INET transport socket.

Link: https://lore.kernel.org/r/166794587113.2389296.16484814996876530222.stgit@warthog.procyon.org.uk/ [1]
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/rxrpc/af_rxrpc.c

@@ -93,12 +93,11 @@ static int rxrpc_validate_address(struct rxrpc_sock *rx,
 	    srx->transport_len > len)
 		return -EINVAL;
 
-	if (srx->transport.family != rx->family &&
-	    srx->transport.family == AF_INET && rx->family != AF_INET6)
-		return -EAFNOSUPPORT;
-
 	switch (srx->transport.family) {
 	case AF_INET:
+		if (rx->family != AF_INET &&
+		    rx->family != AF_INET6)
+			return -EAFNOSUPPORT;
 		if (srx->transport_len < sizeof(struct sockaddr_in))
 			return -EINVAL;
 		tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
@@ -106,6 +105,8 @@ static int rxrpc_validate_address(struct rxrpc_sock *rx,
 
 #ifdef CONFIG_AF_RXRPC_IPV6
 	case AF_INET6:
+		if (rx->family != AF_INET6)
+			return -EAFNOSUPPORT;
 		if (srx->transport_len < sizeof(struct sockaddr_in6))
 			return -EINVAL;
 		tail = offsetof(struct sockaddr_rxrpc, transport) +

net/rxrpc/local_object.c

@@ -33,7 +33,8 @@ static void rxrpc_encap_err_rcv(struct sock *sk, struct sk_buff *skb, int err,
 {
 	if (ip_hdr(skb)->version == IPVERSION)
 		return ip_icmp_error(sk, skb, err, port, info, payload);
-	return ipv6_icmp_error(sk, skb, err, port, info, payload);
+	if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6))
+		return ipv6_icmp_error(sk, skb, err, port, info, payload);
 }
 
 /*

net/rxrpc/output.c

@@ -18,15 +18,21 @@
 
 extern int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
 
-static ssize_t do_udp_sendmsg(struct socket *sk, struct msghdr *msg, size_t len)
+static ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len)
 {
-#if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
 	struct sockaddr *sa = msg->msg_name;
+	struct sock *sk = socket->sk;
 
-	if (sa->sa_family == AF_INET6)
-		return udpv6_sendmsg(sk->sk, msg, len);
-#endif
-	return udp_sendmsg(sk->sk, msg, len);
+	if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6)) {
+		if (sa->sa_family == AF_INET6) {
+			if (sk->sk_family != AF_INET6) {
+				pr_warn("AF_INET6 address on AF_INET socket\n");
+				return -ENOPROTOOPT;
+			}
+			return udpv6_sendmsg(sk, msg, len);
+		}
+	}
+	return udp_sendmsg(sk, msg, len);
 }
 
 struct rxrpc_abort_buffer {