Commit c8e6ad08 authored by Hannes Frederic Sowa's avatar Hannes Frederic Sowa Committed by David S. Miller
Browse files

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: default avatarGert Doering <gert@space.net>
Cc: Tore Anderson <tore@fud.no>
Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 21f374c6

include/net/ip.h

+2 −1
Original line number Diff line number Diff line
@@ -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,

net/ipv4/ip_sockglue.c

+18 −1
Original line number Diff line number Diff line
@@ -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) {

net/ipv4/ping.c

+1 −1
Original line number Diff line number Diff line
@@ -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)

net/ipv4/raw.c

+1 −1
Original line number Diff line number Diff line
@@ -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)

net/ipv4/udp.c

+2 −1
Original line number Diff line number Diff line
@@ -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)

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