vxlan: fix incorrect initializer in union vxlan_addr (a45e92a5) · Commits · 戴 / test

The first initializer in the following union vxlan_addr ipa = { .sin.sin_addr.s_addr = tip, .sa.sa_family = AF_INET, }; is optimised away by the compiler, due to the second initializer, therefore initialising .sin.sin_addr.s_addr always to 0. This results in netlink messages indicating a L3 miss never contain the missed IP address. This was observed with GCC 4.8 and 4.9. I do not know about previous versions. The problem affects user space programs relying on an IP address being sent as part of a netlink message indicating a L3 miss. Changing .sa.sa_family = AF_INET, to .sin.sin_family = AF_INET, fixes the problem. Signed-off-by:

Gerhard Stenzel <gerhard.stenzel@de.ibm.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

drivers/net/vxlan.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -1327,7 +1327,7 @@ static int arp_reduce(struct net_device dev, struct sk_buff skb)
		} else if (vxlan->flags & VXLAN_F_L3MISS) {
		union vxlan_addr ipa = {
		.sin.sin_addr.s_addr = tip,
		.sa.sa_family = AF_INET,
		.sin.sin_family = AF_INET,
		};

		vxlan_ip_miss(dev, &ipa);
		@@ -1488,7 +1488,7 @@ static int neigh_reduce(struct net_device dev, struct sk_buff skb)
		} else if (vxlan->flags & VXLAN_F_L3MISS) {
		union vxlan_addr ipa = {
		.sin6.sin6_addr = msg->target,
		.sa.sa_family = AF_INET6,
		.sin6.sin6_family = AF_INET6,
		};

		vxlan_ip_miss(dev, &ipa);
		@@ -1521,7 +1521,7 @@ static bool route_shortcircuit(struct net_device dev, struct sk_buff skb)
		if (!n && (vxlan->flags & VXLAN_F_L3MISS)) {
		union vxlan_addr ipa = {
		.sin.sin_addr.s_addr = pip->daddr,
		.sa.sa_family = AF_INET,
		.sin.sin_family = AF_INET,
		};

		vxlan_ip_miss(dev, &ipa);
		@@ -1542,7 +1542,7 @@ static bool route_shortcircuit(struct net_device dev, struct sk_buff skb)
		if (!n && (vxlan->flags & VXLAN_F_L3MISS)) {
		union vxlan_addr ipa = {
		.sin6.sin6_addr = pip6->daddr,
		.sa.sa_family = AF_INET6,
		.sin6.sin6_family = AF_INET6,
		};

		vxlan_ip_miss(dev, &ipa);

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