netdev - [PATCH] ipv6: check for IPv4 mapped addresses when connecting IPv6 sockets

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20110804075506.62225813270B@regina.usersys.redhat.com>
Date:	Thu, 4 Aug 2011 17:42:44 +1000
From:	Max Matveev <makc@...hat.com>
To:	netdev@...r.kernel.org
Cc:	vladislav.yasevich@...com
Subject: [PATCH] ipv6: check for IPv4 mapped addresses when connecting IPv6
 sockets

When support for binding to 'mapped INADDR_ANY (::ffff.0.0.0.0)' was added
in 0f8d3c7ac3693d7b6c731bf2159273a59bf70e12 the rest of the code
wasn't told so now it's possible to bind IPv6 datagram socket to
::ffff.0.0.0.0, connect it to another IPv4 address and it will all
work except for getsockhame() which does not return the local address
as expected.

To give getsockname() something to work with check for 'mapped INADDR_ANY'
when connecting and update the in-core source addresses appropriately.

Signed-off-by: Max Matveev <makc@...hat.com>
---
 net/ipv6/datagram.c |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 1656033..d3a65a18 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -33,6 +33,11 @@
 #include <linux/errqueue.h>
 #include <asm/uaccess.h>
 
+static inline int ipv6_mapped_addr_any(const struct in6_addr *a)
+{
+	return (ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0));
+}
+
 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 {
 	struct sockaddr_in6	*usin = (struct sockaddr_in6 *) uaddr;
@@ -102,10 +107,12 @@ ipv4_connected:
 
 		ipv6_addr_set_v4mapped(inet->inet_daddr, &np->daddr);
 
-		if (ipv6_addr_any(&np->saddr))
+		if (ipv6_addr_any(&np->saddr) ||
+		    ipv6_mapped_addr_any(&np->saddr))
 			ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
 
-		if (ipv6_addr_any(&np->rcv_saddr)) {
+		if (ipv6_addr_any(&np->rcv_saddr) || 
+		    ipv6_mapped_addr_any(&np->rcv_saddr)) {
 			ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
 					       &np->rcv_saddr);
 			if (sk->sk_prot->rehash)
-- 
1.7.4.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html