bridge: Fix adding gif(4) interface assigned with IP addresses as bridge memeber

and fix assigning IP addresses to the gif(4) interface when it is a
member of a if_bridge(4) interface.

When setting the sysctl net.link.bridge.member_ifaddrs to 1, if_bridge(4)
can eliminate unnecessary walk of the member list to determine whether
the inbound unicast packets are for us or not.

Well when a gif(4) interface is member of a if_bridge(4) interface, it
acts as the tunnel endpoint to tunnel Ethernet frames over IP network,
aka the EtherIP protocol, so the IP addresses configured on it are
independent of the if_bridge(4) interface or other if_bridge(4) members,
hence the sysctl net.link.bridge.member_ifaddrs should not have any
influnce over gif(4) interfaces's behavior of assigning IP addresses.

PR:		227450
Reported by:	Siva Mahadevan <me@svmhdvn.name>
Reviewed by:	ivy, #bridge
MFC after:	1 week
Fixes:		0a1294f6c610 bridge: allow IP addresses on members to be disabled
Differential Revision:	https://reviews.freebsd.org/D52200

3 files changed, 7 insertions, 7 deletions

diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c
index 66555fd1feb5..a854bbb96394 100644
--- a/sys/net/if_bridge.c
+++ b/sys/net/if_bridge.c
@@ -1447,10 +1447,10 @@ bridge_ioctl_add(struct bridge_softc *sc, void *arg)
 #endif
 
 	/*
-	 * If member_ifaddrs is disabled, do not allow an interface with
-	 * assigned IP addresses to be added to a bridge.
+	 * If member_ifaddrs is disabled, do not allow an Ethernet-like
+	 * interface with assigned IP addresses to be added to a bridge.
 	 */
-	if (!V_member_ifaddrs) {
+	if (!V_member_ifaddrs && ifs->if_type != IFT_GIF) {
 		struct ifaddr *ifa;
 
 		CK_STAILQ_FOREACH(ifa, &ifs->if_addrhead, ifa_link) {
diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index 963449d4b4b1..0e283a7d099d 100644
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -522,8 +522,8 @@ in_aifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct ucred *cred
 	/*
 	 * Check if bridge wants to allow adding addrs to member interfaces.
 	 */
-	if (ifp->if_bridge && bridge_member_ifaddrs_p &&
-	    !bridge_member_ifaddrs_p())
+	if (ifp->if_bridge != NULL && ifp->if_type != IFT_GIF &&
+	    bridge_member_ifaddrs_p != NULL && !bridge_member_ifaddrs_p())
 		return (EINVAL);
 
 	/*
diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index ce0655408a28..a9e6c4eaa51b 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -1236,8 +1236,8 @@ in6_addifaddr(struct ifnet *ifp, struct in6_aliasreq *ifra, struct in6_ifaddr *i
 	int error;
 
 	/* Check if this interface is a bridge member */
-	if (ifp->if_bridge && bridge_member_ifaddrs_p &&
-	    !bridge_member_ifaddrs_p()) {
+	if (ifp->if_bridge != NULL && ifp->if_type != IFT_GIF &&
+	    bridge_member_ifaddrs_p != NULL && !bridge_member_ifaddrs_p()) {
 		error = EINVAL;
 		goto out;
 	}