From c8e6ad0829a723a74cd2fea9996a3392d2579a18 Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Tue, 18 Feb 2014 21:38:08 +0100 Subject: ipv6: honor IPV6_PKTINFO with v4 mapped addresses on sendmsg In case we decide in udp6_sendmsg to send the packet down the ipv4 udp_sendmsg path because the destination is either of family AF_INET or the destination is an ipv4 mapped ipv6 address, we don't honor the maybe specified ipv4 mapped ipv6 address in IPV6_PKTINFO. We simply can check for this option in ip_cmsg_send because no calls to ipv6 module functions are needed to do so. Reported-by: Gert Doering Cc: Tore Anderson Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/ipv4/ip_sockglue.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'net/ipv4/ip_sockglue.c') diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 580dd96666e0..0968b28c4cf3 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -186,7 +186,8 @@ void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb) } EXPORT_SYMBOL(ip_cmsg_recv); -int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc) +int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc, + bool allow_ipv6) { int err, val; struct cmsghdr *cmsg; @@ -194,6 +195,22 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc) for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { if (!CMSG_OK(msg, cmsg)) return -EINVAL; +#if defined(CONFIG_IPV6) + if (allow_ipv6 && + cmsg->cmsg_level == SOL_IPV6 && + cmsg->cmsg_type == IPV6_PKTINFO) { + struct in6_pktinfo *src_info; + + if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info))) + return -EINVAL; + src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); + if (!ipv6_addr_v4mapped(&src_info->ipi6_addr)) + return -EINVAL; + ipc->oif = src_info->ipi6_ifindex; + ipc->addr = src_info->ipi6_addr.s6_addr32[3]; + continue; + } +#endif if (cmsg->cmsg_level != SOL_IP) continue; switch (cmsg->cmsg_type) { -- cgit v1.2.3