From c8e6ad0829a723a74cd2fea9996a3392d2579a18 Mon Sep 17 00:00:00 2001 From: Hannes Frederic Sowa Date: Tue, 18 Feb 2014 21:38:08 +0100 Subject: [PATCH] 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 --- include/net/ip.h | 3 ++- net/ipv4/ip_sockglue.c | 19 ++++++++++++++++++- net/ipv4/ping.c | 2 +- net/ipv4/raw.c | 2 +- net/ipv4/udp.c | 3 ++- 5 files changed, 24 insertions(+), 5 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index 23be0fd37937..4aa781b7f609 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -489,7 +489,8 @@ int ip_options_rcv_srr(struct sk_buff *skb); void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb); void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb); -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 ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen); int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, 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) { diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 2d11c094296e..f4b19e5dde54 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -727,7 +727,7 @@ static int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m sock_tx_timestamp(sk, &ipc.tx_flags); if (msg->msg_controllen) { - err = ip_cmsg_send(sock_net(sk), msg, &ipc); + err = ip_cmsg_send(sock_net(sk), msg, &ipc, false); if (err) return err; if (ipc.opt) diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index c04518f4850a..a9dbe58bdfe7 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -524,7 +524,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, ipc.oif = sk->sk_bound_dev_if; if (msg->msg_controllen) { - err = ip_cmsg_send(sock_net(sk), msg, &ipc); + err = ip_cmsg_send(sock_net(sk), msg, &ipc, false); if (err) goto out; if (ipc.opt) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 77bd16fa9f34..4468e1adc094 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -931,7 +931,8 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, sock_tx_timestamp(sk, &ipc.tx_flags); if (msg->msg_controllen) { - err = ip_cmsg_send(sock_net(sk), msg, &ipc); + err = ip_cmsg_send(sock_net(sk), msg, &ipc, + sk->sk_family == AF_INET6); if (err) return err; if (ipc.opt) -- 2.34.1