[MPTCP] Re: [MPTCP][PATCH v8 mptcp-next 3/8] mptcp: add port number announced check

When we received the MP_JOIN's SYN/ACK, we do the port number checks. If the subflow's source port number is different, we use a new helper mptcp_pm_sport_in_anno_list to check whether this port number is announced. If it isn't, we need to abort this connection. Signed-off-by: Geliang Tang <geliangtang(a)gmail.com&gt; --- net/mptcp/pm_netlink.c | 23 ++++++++++++++++++++++- net/mptcp/protocol.h | 1 + net/mptcp/subflow.c | 10 ++++++++++ 3 files changed, 33 insertions(+), 1 deletion(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 1548efb22a1b..221bf997dcf4 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -92,8 +92,8 @@ static bool address_zero(const struct mptcp_addr_info *addr) static void local_address(const struct sock_common *skc, struct mptcp_addr_info *addr) { - addr->port = 0; addr->family = skc->skc_family; + addr->port = htons(skc->skc_num); if (addr->family == AF_INET) addr->addr.s_addr = skc->skc_rcv_saddr; #if IS_ENABLED(CONFIG_MPTCP_IPV6) @@ -204,6 +204,27 @@ lookup_anno_list_by_saddr(struct mptcp_sock *msk, return NULL; } +bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk) +{ + struct mptcp_pm_add_entry *entry; + struct mptcp_addr_info saddr; + bool ret = false; + + local_address((struct sock_common *)sk, &saddr); + + spin_lock_bh(&msk->pm.lock); + list_for_each_entry(entry, &msk->pm.anno_list, list) { + if (addresses_equal(&entry->addr, &saddr, true)) { + ret = true; + goto out; + } + } + +out: + spin_unlock_bh(&msk->pm.lock); + return ret; +} + static void mptcp_pm_add_timer(struct timer_list *timer) { struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer); diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index a2a031cca97a..d700ee1a05bb 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -565,6 +565,7 @@ int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk, struct mptcp_addr_info *addr, u8 bkup); void mptcp_pm_free_anno_list(struct mptcp_sock *msk); +bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk); struct mptcp_pm_add_entry * mptcp_pm_del_add_timer(struct mptcp_sock *msk, struct mptcp_addr_info *addr); diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 398554590bf1..01d192c1acf7 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -193,6 +193,14 @@ static int subflow_init_req(struct request_sock *req, pr_debug("syn inet_sport=%d %d", ntohs(inet_sk(sk_listener)->inet_sport), ntohs(inet_sk((struct sock *)subflow_req->msk)->inet_sport)); + if (!mptcp_pm_sport_in_anno_list(subflow_req->msk, sk_listener)) { + sock_put((struct sock *)subflow_req->msk); + mptcp_token_destroy_request(req); + tcp_request_sock_ops.destructor(req); + subflow_req->msk = NULL; + subflow_req->mp_join = 0; + return -EPERM; + } }

if (unlikely(req->syncookie)) { @@ -680,6 +688,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock *sk, pr_debug("ack inet_sport=%d %d", ntohs(inet_sk(sk)->inet_sport), ntohs(inet_sk((struct sock *)owner)->inet_sport)); + if (!mptcp_pm_sport_in_anno_list(owner, sk)) + goto out; } } } -- 2.29.2