diff --git a/include/net/mptcp.h b/include/net/mptcp.h
index 0a3b0fb04a3b9..8b1afd6f5cc46 100644
--- a/include/net/mptcp.h
+++ b/include/net/mptcp.h
@@ -35,7 +35,8 @@ struct mptcp_ext {
 			frozen:1,
 			reset_transient:1;
 	u8		reset_reason:4,
-			csum_reqd:1;
+			csum_reqd:1,
+			infinite_map:1;
 };
 
 #define MPTCP_RM_IDS_MAX	8
diff --git a/include/trace/events/mptcp.h b/include/trace/events/mptcp.h
index f8e28e686c65f..563e48617374d 100644
--- a/include/trace/events/mptcp.h
+++ b/include/trace/events/mptcp.h
@@ -84,6 +84,7 @@ DECLARE_EVENT_CLASS(mptcp_dump_mpext,
 		__field(u8, reset_transient)
 		__field(u8, reset_reason)
 		__field(u8, csum_reqd)
+		__field(u8, infinite_map)
 	),
 
 	TP_fast_assign(
@@ -102,9 +103,10 @@ DECLARE_EVENT_CLASS(mptcp_dump_mpext,
 		__entry->reset_transient = mpext->reset_transient;
 		__entry->reset_reason = mpext->reset_reason;
 		__entry->csum_reqd = mpext->csum_reqd;
+		__entry->infinite_map = mpext->infinite_map;
 	),
 
-	TP_printk("data_ack=%llu data_seq=%llu subflow_seq=%u data_len=%u csum=%x use_map=%u dsn64=%u data_fin=%u use_ack=%u ack64=%u mpc_map=%u frozen=%u reset_transient=%u reset_reason=%u csum_reqd=%u",
+	TP_printk("data_ack=%llu data_seq=%llu subflow_seq=%u data_len=%u csum=%x use_map=%u dsn64=%u data_fin=%u use_ack=%u ack64=%u mpc_map=%u frozen=%u reset_transient=%u reset_reason=%u csum_reqd=%u infinite_map=%u",
 		  __entry->data_ack, __entry->data_seq,
 		  __entry->subflow_seq, __entry->data_len,
 		  __entry->csum, __entry->use_map,
@@ -112,7 +114,7 @@ DECLARE_EVENT_CLASS(mptcp_dump_mpext,
 		  __entry->use_ack, __entry->ack64,
 		  __entry->mpc_map, __entry->frozen,
 		  __entry->reset_transient, __entry->reset_reason,
-		  __entry->csum_reqd)
+		  __entry->csum_reqd, __entry->infinite_map)
 );
 
 DEFINE_EVENT(mptcp_dump_mpext, mptcp_sendmsg_frag,
diff --git a/net/mptcp/mib.c b/net/mptcp/mib.c
index e55d3dfbee0c3..d93a8c9996fd0 100644
--- a/net/mptcp/mib.c
+++ b/net/mptcp/mib.c
@@ -24,6 +24,7 @@ static const struct snmp_mib mptcp_snmp_list[] = {
 	SNMP_MIB_ITEM("MPJoinAckRx", MPTCP_MIB_JOINACKRX),
 	SNMP_MIB_ITEM("MPJoinAckHMacFailure", MPTCP_MIB_JOINACKMAC),
 	SNMP_MIB_ITEM("DSSNotMatching", MPTCP_MIB_DSSNOMATCH),
+	SNMP_MIB_ITEM("InfiniteMapTx", MPTCP_MIB_INFINITEMAPTX),
 	SNMP_MIB_ITEM("InfiniteMapRx", MPTCP_MIB_INFINITEMAPRX),
 	SNMP_MIB_ITEM("DSSNoMatchTCP", MPTCP_MIB_DSSTCPMISMATCH),
 	SNMP_MIB_ITEM("DataCsumErr", MPTCP_MIB_DATACSUMERR),
diff --git a/net/mptcp/mib.h b/net/mptcp/mib.h
index 00576179a619f..529d07af9e145 100644
--- a/net/mptcp/mib.h
+++ b/net/mptcp/mib.h
@@ -17,6 +17,7 @@ enum linux_mptcp_mib_field {
 	MPTCP_MIB_JOINACKRX,		/* Received an ACK + MP_JOIN */
 	MPTCP_MIB_JOINACKMAC,		/* HMAC was wrong on ACK + MP_JOIN */
 	MPTCP_MIB_DSSNOMATCH,		/* Received a new mapping that did not match the previous one */
+	MPTCP_MIB_INFINITEMAPTX,	/* Sent an infinite mapping */
 	MPTCP_MIB_INFINITEMAPRX,	/* Received an infinite mapping */
 	MPTCP_MIB_DSSTCPMISMATCH,	/* DSS-mapping did not map with TCP's sequence numbers */
 	MPTCP_MIB_DATACSUMERR,		/* The data checksum fail */
diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 325383646f5c0..88f4ebbd6515b 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -825,7 +825,7 @@ bool mptcp_established_options(struct sock *sk, struct sk_buff *skb,
 
 	opts->suboptions = 0;
 
-	if (unlikely(__mptcp_check_fallback(msk)))
+	if (unlikely(__mptcp_check_fallback(msk) && !mptcp_check_infinite_map(skb)))
 		return false;
 
 	if (unlikely(skb && TCP_SKB_CB(skb)->tcp_flags & TCPHDR_RST)) {
@@ -1340,8 +1340,12 @@ void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp,
 			put_unaligned_be32(mpext->subflow_seq, ptr);
 			ptr += 1;
 			if (opts->csum_reqd) {
+				/* data_len == 0 is reserved for the infinite mapping,
+				 * the checksum will also be set to 0.
+				 */
 				put_unaligned_be32(mpext->data_len << 16 |
-						   mptcp_make_csum(mpext), ptr);
+						   (mpext->data_len ? mptcp_make_csum(mpext) : 0),
+						   ptr);
 			} else {
 				put_unaligned_be32(mpext->data_len << 16 |
 						   TCPOPT_NOP << 8 | TCPOPT_NOP, ptr);
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 8aa0cdb7ad46a..5c36870d3420b 100644
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -285,7 +285,13 @@ void mptcp_pm_mp_prio_received(struct sock *ssk, u8 bkup)
 
 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq)
 {
+	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
+	struct mptcp_sock *msk = mptcp_sk(subflow->conn);
+
 	pr_debug("fail_seq=%llu", fail_seq);
+
+	if (!mptcp_has_another_subflow(sk) && READ_ONCE(msk->allow_infinite_fallback))
+		subflow->send_infinite_map = 1;
 }
 
 /* path manager helpers */
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 0492aa9308c77..4581c570ef682 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1229,6 +1229,22 @@ static void mptcp_update_data_checksum(struct sk_buff *skb, int added)
 	mpext->csum = csum_fold(csum_block_add(csum, skb_checksum(skb, offset, added, 0), offset));
 }
 
+static void mptcp_update_infinite_map(struct mptcp_sock *msk,
+				      struct sock *ssk,
+				      struct mptcp_ext *mpext)
+{
+	if (!mpext)
+		return;
+
+	mpext->infinite_map = 1;
+	mpext->data_len = 0;
+
+	MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPTX);
+	mptcp_subflow_ctx(ssk)->send_infinite_map = 0;
+	pr_fallback(msk);
+	__mptcp_do_fallback(msk);
+}
+
 static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk,
 			      struct mptcp_data_frag *dfrag,
 			      struct mptcp_sendmsg_info *info)
@@ -1360,6 +1376,8 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk,
 out:
 	if (READ_ONCE(msk->csum_enabled))
 		mptcp_update_data_checksum(skb, copy);
+	if (mptcp_subflow_ctx(ssk)->send_infinite_map)
+		mptcp_update_infinite_map(msk, ssk, mpext);
 	trace_mptcp_sendmsg_frag(mpext);
 	mptcp_subflow_ctx(ssk)->rel_write_seq += copy;
 	return copy;
@@ -2465,6 +2483,7 @@ static void __mptcp_retrans(struct sock *sk)
 		dfrag->already_sent = max(dfrag->already_sent, info.sent);
 		tcp_push(ssk, 0, info.mss_now, tcp_sk(ssk)->nonagle,
 			 info.size_goal);
+		WRITE_ONCE(msk->allow_infinite_fallback, false);
 	}
 
 	release_sock(ssk);
@@ -2539,6 +2558,7 @@ static int __mptcp_init_sock(struct sock *sk)
 	msk->first = NULL;
 	inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss;
 	WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk)));
+	WRITE_ONCE(msk->allow_infinite_fallback, true);
 	msk->recovery = false;
 
 	mptcp_pm_data_init(msk);
@@ -3275,6 +3295,7 @@ bool mptcp_finish_join(struct sock *ssk)
 	}
 
 	subflow->map_seq = READ_ONCE(msk->ack_seq);
+	WRITE_ONCE(msk->allow_infinite_fallback, false);
 
 out:
 	mptcp_event(MPTCP_EVENT_SUB_ESTABLISHED, msk, ssk, GFP_ATOMIC);
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index aca1fb56523f6..61d600693ffd0 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -263,6 +263,7 @@ struct mptcp_sock {
 	bool		rcv_fastclose;
 	bool		use_64bit_ack; /* Set when we received a 64-bit DSN */
 	bool		csum_enabled;
+	bool		allow_infinite_fallback;
 	u8		recvmsg_inq:1,
 			cork:1,
 			nodelay:1;
@@ -440,6 +441,7 @@ struct mptcp_subflow_context {
 		send_mp_prio : 1,
 		send_mp_fail : 1,
 		send_fastclose : 1,
+		send_infinite_map : 1,
 		rx_eof : 1,
 		can_ack : 1,        /* only after processing the remote a key */
 		disposable : 1,	    /* ctx can be free at ulp release time */
@@ -876,6 +878,17 @@ static inline void mptcp_do_fallback(struct sock *sk)
 
 #define pr_fallback(a) pr_debug("%s:fallback to TCP (msk=%p)", __func__, a)
 
+static inline bool mptcp_check_infinite_map(struct sk_buff *skb)
+{
+	struct mptcp_ext *mpext;
+
+	mpext = skb ? mptcp_get_ext(skb) : NULL;
+	if (mpext && mpext->infinite_map)
+		return true;
+
+	return false;
+}
+
 static inline bool subflow_simultaneous_connect(struct sock *sk)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index aba260f547daa..30ffb00661bb9 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1006,7 +1006,9 @@ static enum mapping_status get_mapping_status(struct sock *ssk,
 
 	data_len = mpext->data_len;
 	if (data_len == 0) {
+		pr_debug("infinite mapping received");
 		MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX);
+		subflow->map_data_len = 0;
 		return MAPPING_INVALID;
 	}
 
@@ -1203,35 +1205,39 @@ static bool subflow_check_data_avail(struct sock *ssk)
 	return false;
 
 fallback:
-	/* RFC 8684 section 3.7. */
-	if (subflow->send_mp_fail) {
-		if (mptcp_has_another_subflow(ssk)) {
-			while ((skb = skb_peek(&ssk->sk_receive_queue)))
-				sk_eat_skb(ssk, skb);
+	if (!__mptcp_check_fallback(msk)) {
+		/* RFC 8684 section 3.7. */
+		if (subflow->send_mp_fail) {
+			if (mptcp_has_another_subflow(ssk) ||
+			    !READ_ONCE(msk->allow_infinite_fallback)) {
+				ssk->sk_err = EBADMSG;
+				tcp_set_state(ssk, TCP_CLOSE);
+				subflow->reset_transient = 0;
+				subflow->reset_reason = MPTCP_RST_EMIDDLEBOX;
+				tcp_send_active_reset(ssk, GFP_ATOMIC);
+				while ((skb = skb_peek(&ssk->sk_receive_queue)))
+					sk_eat_skb(ssk, skb);
+			}
+			WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
+			return true;
 		}
-		ssk->sk_err = EBADMSG;
-		tcp_set_state(ssk, TCP_CLOSE);
-		subflow->reset_transient = 0;
-		subflow->reset_reason = MPTCP_RST_EMIDDLEBOX;
-		tcp_send_active_reset(ssk, GFP_ATOMIC);
-		WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
-		return true;
-	}
 
-	if (subflow->mp_join || subflow->fully_established) {
-		/* fatal protocol error, close the socket.
-		 * subflow_error_report() will introduce the appropriate barriers
-		 */
-		ssk->sk_err = EBADMSG;
-		tcp_set_state(ssk, TCP_CLOSE);
-		subflow->reset_transient = 0;
-		subflow->reset_reason = MPTCP_RST_EMPTCP;
-		tcp_send_active_reset(ssk, GFP_ATOMIC);
-		WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
-		return false;
+		if ((subflow->mp_join || subflow->fully_established) && subflow->map_data_len) {
+			/* fatal protocol error, close the socket.
+			 * subflow_error_report() will introduce the appropriate barriers
+			 */
+			ssk->sk_err = EBADMSG;
+			tcp_set_state(ssk, TCP_CLOSE);
+			subflow->reset_transient = 0;
+			subflow->reset_reason = MPTCP_RST_EMPTCP;
+			tcp_send_active_reset(ssk, GFP_ATOMIC);
+			WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
+			return false;
+		}
+
+		__mptcp_do_fallback(msk);
 	}
 
-	__mptcp_do_fallback(msk);
 	skb = skb_peek(&ssk->sk_receive_queue);
 	subflow->map_valid = 1;
 	subflow->map_seq = READ_ONCE(msk->ack_seq);
@@ -1483,6 +1489,7 @@ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc,
 	/* discard the subflow socket */
 	mptcp_sock_graft(ssk, sk->sk_socket);
 	iput(SOCK_INODE(sf));
+	WRITE_ONCE(msk->allow_infinite_fallback, false);
 	return err;
 
 failed_unlink:
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 7314257d248a7..9eb4d889a24a1 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -1106,6 +1106,38 @@ chk_rst_nr()
 	echo "$extra_msg"
 }
 
+chk_infi_nr()
+{
+	local infi_tx=$1
+	local infi_rx=$2
+	local count
+	local dump_stats
+
+	printf "%-${nr_blank}s %s" " " "itx"
+	count=$(ip netns exec $ns2 nstat -as | grep InfiniteMapTx | awk '{print $2}')
+	[ -z "$count" ] && count=0
+	if [ "$count" != "$infi_tx" ]; then
+		echo "[fail] got $count infinite map[s] TX expected $infi_tx"
+		fail_test
+		dump_stats=1
+	else
+		echo -n "[ ok ]"
+	fi
+
+	echo -n " - infirx"
+	count=$(ip netns exec $ns1 nstat -as | grep InfiniteMapRx | awk '{print $2}')
+	[ -z "$count" ] && count=0
+	if [ "$count" != "$infi_rx" ]; then
+		echo "[fail] got $count infinite map[s] RX expected $infi_rx"
+		fail_test
+		dump_stats=1
+	else
+		echo "[ ok ]"
+	fi
+
+	[ "${dump_stats}" = 1 ] && dump_stats
+}
+
 chk_join_nr()
 {
 	local syn_nr=$1
@@ -1115,7 +1147,8 @@ chk_join_nr()
 	local csum_ns2=${5:-0}
 	local fail_nr=${6:-0}
 	local rst_nr=${7:-0}
-	local corrupted_pkts=${8:-0}
+	local infi_nr=${8:-0}
+	local corrupted_pkts=${9:-0}
 	local count
 	local dump_stats
 	local with_cookie
@@ -1170,6 +1203,7 @@ chk_join_nr()
 		chk_csum_nr $csum_ns1 $csum_ns2
 		chk_fail_nr $fail_nr $fail_nr
 		chk_rst_nr $rst_nr $rst_nr
+		chk_infi_nr $infi_nr $infi_nr
 	fi
 }