From 50a13bc3945c9004cf418d181d55ec54cfe4c8ec Mon Sep 17 00:00:00 2001 From: Matthieu Baerts Date: Mon, 25 Jan 2021 10:59:00 -0800 Subject: [PATCH] mptcp: support MPJoin with IPv4 mapped in v6 sk With an IPv4 mapped in v6 socket, we were trying to call inet6_bind() with an IPv4 address resulting in a -EINVAL error because the given addr_len -- size of the address structure -- was too short. We now make sure to use address structures for the same family as the MPTCP socket for both the bind() and the connect(). It means we convert v4 addresses to v4 mapped in v6 or the opposite if needed. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/122 Co-developed-by: Geliang Tang Signed-off-by: Geliang Tang Signed-off-by: Matthieu Baerts Signed-off-by: Mat Martineau Signed-off-by: Jakub Kicinski --- net/mptcp/subflow.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 7210599..5861562 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1085,21 +1085,31 @@ void mptcpv6_handle_mapped(struct sock *sk, bool mapped) #endif static void mptcp_info2sockaddr(const struct mptcp_addr_info *info, - struct sockaddr_storage *addr) + struct sockaddr_storage *addr, + unsigned short family) { memset(addr, 0, sizeof(*addr)); - addr->ss_family = info->family; + addr->ss_family = family; if (addr->ss_family == AF_INET) { struct sockaddr_in *in_addr = (struct sockaddr_in *)addr; - in_addr->sin_addr = info->addr; + if (info->family == AF_INET) + in_addr->sin_addr = info->addr; +#if IS_ENABLED(CONFIG_MPTCP_IPV6) + else if (ipv6_addr_v4mapped(&info->addr6)) + in_addr->sin_addr.s_addr = info->addr6.s6_addr32[3]; +#endif in_addr->sin_port = info->port; } #if IS_ENABLED(CONFIG_MPTCP_IPV6) else if (addr->ss_family == AF_INET6) { struct sockaddr_in6 *in6_addr = (struct sockaddr_in6 *)addr; - in6_addr->sin6_addr = info->addr6; + if (info->family == AF_INET) + ipv6_addr_set_v4mapped(info->addr.s_addr, + &in6_addr->sin6_addr); + else + in6_addr->sin6_addr = info->addr6; in6_addr->sin6_port = info->port; } #endif @@ -1143,11 +1153,11 @@ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, subflow->remote_key = msk->remote_key; subflow->local_key = msk->local_key; subflow->token = msk->token; - mptcp_info2sockaddr(loc, &addr); + mptcp_info2sockaddr(loc, &addr, ssk->sk_family); addrlen = sizeof(struct sockaddr_in); #if IS_ENABLED(CONFIG_MPTCP_IPV6) - if (loc->family == AF_INET6) + if (addr.ss_family == AF_INET6) addrlen = sizeof(struct sockaddr_in6); #endif ssk->sk_bound_dev_if = loc->ifindex; @@ -1163,7 +1173,7 @@ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc, subflow->remote_id = remote_id; subflow->request_join = 1; subflow->request_bkup = !!(loc->flags & MPTCP_PM_ADDR_FLAG_BACKUP); - mptcp_info2sockaddr(remote, &addr); + mptcp_info2sockaddr(remote, &addr, ssk->sk_family); mptcp_add_pending_subflow(msk, subflow); err = kernel_connect(sf, (struct sockaddr *)&addr, addrlen, O_NONBLOCK); -- 2.7.4