[Devel] [PATCH 3/7 net-2.6.25] [IPV4]: Prohibit assignment of 0.0.0.0 as interface address.

[Denis V. Lunev]

I could hardly imagine why sombady needs to assign 0.0.0.0 as an interface
address or interface destination address. The kernel will behave in a strage
way in several places if this is possible, as ifa_local != 0 is considered
as initialized/non-initialized state of the ifa.

Signed-off-by: Denis V. Lunev <den at openvz.org>
---
 net/ipv4/devinet.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 9da4c68..e55c85e 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -534,7 +534,13 @@ static struct in_ifaddr *rtm_to_ifaddr(struct nlmsghdr *nlh)
 	ifa->ifa_dev = in_dev;
 
 	ifa->ifa_local = nla_get_be32(tb[IFA_LOCAL]);
+	err = -EINVAL;
+	if (ifa->ifa_local == htonl(INADDR_ANY))
+		goto fail_free;
+
 	ifa->ifa_address = nla_get_be32(tb[IFA_ADDRESS]);
+	if (ifa->ifa_address == htonl(INADDR_ANY))
+		goto fail_free;
 
 	if (tb[IFA_BROADCAST])
 		ifa->ifa_broadcast = nla_get_be32(tb[IFA_BROADCAST]);
@@ -549,6 +555,8 @@ static struct in_ifaddr *rtm_to_ifaddr(struct nlmsghdr *nlh)
 
 	return ifa;
 
+fail_free:
+	inet_free_ifa(ifa);
 errout:
 	return ERR_PTR(err);
 }
@@ -736,6 +744,8 @@ int devinet_ioctl(unsigned int cmd, void __user *arg)
 		ret = -EINVAL;
 		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
 			break;
+		if (sin->sin_addr.s_addr == INADDR_ANY)
+			break;
 
 		if (!ifa) {
 			ret = -ENOBUFS;
@@ -786,6 +796,8 @@ int devinet_ioctl(unsigned int cmd, void __user *arg)
 		ret = -EINVAL;
 		if (inet_abc_len(sin->sin_addr.s_addr) < 0)
 			break;
+		if (sin->sin_addr.s_addr == INADDR_ANY)
+			break;
 		ret = 0;
 		inet_del_ifa(in_dev, ifap, 0);
 		ifa->ifa_address = sin->sin_addr.s_addr;
-- 
1.5.3.rc5