Merge branch 'mptcp-next'

Mat Martineau says:

====================
mptcp: New features and cleanup

These patches have been tested in the MPTCP tree for a longer than usual
time (thanks to holiday schedules), and are ready for the net-next
branch. Changes include feature updates, small fixes, refactoring, and
some selftest changes.

Patch 1 fixes an OUTQ ioctl issue with TCP fallback sockets.

Patches 2, 3, and 6 add support of the MPTCP fastclose option (quick
shutdown of the full MPTCP connection, similar to TCP RST in regular
TCP), and a related self test.

Patch 4 cleans up some accept and poll code that is no longer needed
after the fastclose changes.

Patch 5 add userspace disconnect using AF_UNSPEC, which is used when
testing fastclose and makes the MPTCP socket's handling of AF_UNSPEC in
connect() more TCP-like.

Patches 7-11 refactor subflow creation to make better use of multiple
local endpoints and to better handle individual connection failures when
creating multiple subflows. Includes self test updates.

Patch 12 cleans up the way subflows are added to the MPTCP connection
list, eliminating the need for calls throughout the MPTCP code that had
to check the intermediate "join list" for entries to shift over to the
main "connection list".

Patch 13 refactors the MPTCP release_cb flags to use separate storage
for values only accessed with the socket lock held (no atomic ops
needed), and for values that need atomic operations.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 242 insertions, 29 deletions

diff --git a/tools/testing/selftests/net/mptcp/config b/tools/testing/selftests/net/mptcp/config
index d548bc139b5d..d36b7da5082a 100644
--- a/tools/testing/selftests/net/mptcp/config
+++ b/tools/testing/selftests/net/mptcp/config
@@ -17,4 +17,5 @@ CONFIG_NFT_TPROXY=m
 CONFIG_NFT_SOCKET=m
 CONFIG_IP_ADVANCED_ROUTER=y
 CONFIG_IP_MULTIPLE_TABLES=y
+CONFIG_IP_NF_TARGET_REJECT=m
 CONFIG_IPV6_MULTIPLE_TABLES=y
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.c b/tools/testing/selftests/net/mptcp/mptcp_connect.c
index a30e93c5c549..8628aa61b763 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.c
@@ -16,6 +16,7 @@
 #include <unistd.h>
 #include <time.h>
 
+#include <sys/ioctl.h>
 #include <sys/poll.h>
 #include <sys/sendfile.h>
 #include <sys/stat.h>
@@ -28,6 +29,7 @@
 
 #include <linux/tcp.h>
 #include <linux/time_types.h>
+#include <linux/sockios.h>
 
 extern int optind;
 
@@ -68,6 +70,8 @@ static unsigned int cfg_time;
 static unsigned int cfg_do_w;
 static int cfg_wait;
 static uint32_t cfg_mark;
+static char *cfg_input;
+static int cfg_repeat = 1;
 
 struct cfg_cmsg_types {
 	unsigned int cmsg_enabled:1;
@@ -91,22 +95,31 @@ static struct cfg_sockopt_types cfg_sockopt_types;
 
 static void die_usage(void)
 {
-	fprintf(stderr, "Usage: mptcp_connect [-6] [-u] [-s MPTCP|TCP] [-p port] [-m mode]"
-		"[-l] [-w sec] [-t num] [-T num] connect_address\n");
+	fprintf(stderr, "Usage: mptcp_connect [-6] [-c cmsg] [-i file] [-I num] [-j] [-l] "
+		"[-m mode] [-M mark] [-o option] [-p port] [-P mode] [-j] [-l] [-r num] "
+		"[-s MPTCP|TCP] [-S num] [-r num] [-t num] [-T num] [-u] [-w sec] connect_address\n");
 	fprintf(stderr, "\t-6 use ipv6\n");
-	fprintf(stderr, "\t-t num -- set poll timeout to num\n");
-	fprintf(stderr, "\t-T num -- set expected runtime to num ms\n");
-	fprintf(stderr, "\t-S num -- set SO_SNDBUF to num\n");
-	fprintf(stderr, "\t-R num -- set SO_RCVBUF to num\n");
-	fprintf(stderr, "\t-p num -- use port num\n");
-	fprintf(stderr, "\t-s [MPTCP|TCP] -- use mptcp(default) or tcp sockets\n");
+	fprintf(stderr, "\t-c cmsg -- test cmsg type <cmsg>\n");
+	fprintf(stderr, "\t-i file -- read the data to send from the given file instead of stdin");
+	fprintf(stderr, "\t-I num -- repeat the transfer 'num' times. In listen mode accepts num "
+		"incoming connections, in client mode, disconnect and reconnect to the server\n");
+	fprintf(stderr, "\t-j     -- add additional sleep at connection start and tear down "
+		"-- for MPJ tests\n");
+	fprintf(stderr, "\t-l     -- listens mode, accepts incoming connection\n");
 	fprintf(stderr, "\t-m [poll|mmap|sendfile] -- use poll(default)/mmap+write/sendfile\n");
 	fprintf(stderr, "\t-M mark -- set socket packet mark\n");
-	fprintf(stderr, "\t-w num -- wait num sec before closing the socket\n");
-	fprintf(stderr, "\t-c cmsg -- test cmsg type <cmsg>\n");
 	fprintf(stderr, "\t-o option -- test sockopt <option>\n");
+	fprintf(stderr, "\t-p num -- use port num\n");
 	fprintf(stderr,
 		"\t-P [saveWithPeek|saveAfterPeek] -- save data with/after MSG_PEEK form tcp socket\n");
+	fprintf(stderr, "\t-t num -- set poll timeout to num\n");
+	fprintf(stderr, "\t-T num -- set expected runtime to num ms\n");
+	fprintf(stderr, "\t-r num -- enable slow mode, limiting each write to num bytes "
+		"-- for remove addr tests\n");
+	fprintf(stderr, "\t-R num -- set SO_RCVBUF to num\n");
+	fprintf(stderr, "\t-s [MPTCP|TCP] -- use mptcp(default) or tcp sockets\n");
+	fprintf(stderr, "\t-S num -- set SO_SNDBUF to num\n");
+	fprintf(stderr, "\t-w num -- wait num sec before closing the socket\n");
 	exit(1);
 }
 
@@ -310,7 +323,8 @@ static int sock_listen_mptcp(const char * const listenaddr,
 }
 
 static int sock_connect_mptcp(const char * const remoteaddr,
-			      const char * const port, int proto)
+			      const char * const port, int proto,
+			      struct addrinfo **peer)
 {
 	struct addrinfo hints = {
 		.ai_protocol = IPPROTO_TCP,
@@ -334,8 +348,10 @@ static int sock_connect_mptcp(const char * const remoteaddr,
 		if (cfg_mark)
 			set_mark(sock, cfg_mark);
 
-		if (connect(sock, a->ai_addr, a->ai_addrlen) == 0)
+		if (connect(sock, a->ai_addr, a->ai_addrlen) == 0) {
+			*peer = a;
 			break; /* success */
+		}
 
 		perror("connect()");
 		close(sock);
@@ -524,14 +540,17 @@ static ssize_t do_rnd_read(const int fd, char *buf, const size_t len)
 	return ret;
 }
 
-static void set_nonblock(int fd)
+static void set_nonblock(int fd, bool nonblock)
 {
 	int flags = fcntl(fd, F_GETFL);
 
 	if (flags == -1)
 		return;
 
-	fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+	if (nonblock)
+		fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+	else
+		fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
 }
 
 static int copyfd_io_poll(int infd, int peerfd, int outfd, bool *in_closed_after_out)
@@ -543,7 +562,7 @@ static int copyfd_io_poll(int infd, int peerfd, int outfd, bool *in_closed_after
 	unsigned int woff = 0, wlen = 0;
 	char wbuf[8192];
 
-	set_nonblock(peerfd);
+	set_nonblock(peerfd, true);
 
 	for (;;) {
 		char rbuf[8192];
@@ -638,7 +657,6 @@ static int copyfd_io_poll(int infd, int peerfd, int outfd, bool *in_closed_after
 	if (cfg_remove)
 		usleep(cfg_wait);
 
-	close(peerfd);
 	return 0;
 }
 
@@ -780,7 +798,7 @@ static int copyfd_io_sendfile(int infd, int peerfd, int outfd,
 	return err;
 }
 
-static int copyfd_io(int infd, int peerfd, int outfd)
+static int copyfd_io(int infd, int peerfd, int outfd, bool close_peerfd)
 {
 	bool in_closed_after_out = false;
 	struct timespec start, end;
@@ -819,6 +837,9 @@ static int copyfd_io(int infd, int peerfd, int outfd)
 	if (ret)
 		return ret;
 
+	if (close_peerfd)
+		close(peerfd);
+
 	if (cfg_time) {
 		unsigned int delta_ms;
 
@@ -930,7 +951,7 @@ static void maybe_close(int fd)
 {
 	unsigned int r = rand();
 
-	if (!(cfg_join || cfg_remove) && (r & 1))
+	if (!(cfg_join || cfg_remove || cfg_repeat > 1) && (r & 1))
 		close(fd);
 }
 
@@ -940,7 +961,9 @@ int main_loop_s(int listensock)
 	struct pollfd polls;
 	socklen_t salen;
 	int remotesock;
+	int fd = 0;
 
+again:
 	polls.fd = listensock;
 	polls.events = POLLIN;
 
@@ -961,14 +984,27 @@ int main_loop_s(int listensock)
 		check_sockaddr(pf, &ss, salen);
 		check_getpeername(remotesock, &ss, salen);
 
+		if (cfg_input) {
+			fd = open(cfg_input, O_RDONLY);
+			if (fd < 0)
+				xerror("can't open %s: %d", cfg_input, errno);
+		}
+
 		SOCK_TEST_TCPULP(remotesock, 0);
 
-		return copyfd_io(0, remotesock, 1);
+		copyfd_io(fd, remotesock, 1, true);
+	} else {
+		perror("accept");
+		return 1;
 	}
 
-	perror("accept");
+	if (--cfg_repeat > 0) {
+		if (cfg_input)
+			close(fd);
+		goto again;
+	}
 
-	return 1;
+	return 0;
 }
 
 static void init_rng(void)
@@ -1057,15 +1093,47 @@ static void parse_setsock_options(const char *name)
 	exit(1);
 }
 
+void xdisconnect(int fd, int addrlen)
+{
+	struct sockaddr_storage empty;
+	int msec_sleep = 10;
+	int queued = 1;
+	int i;
+
+	shutdown(fd, SHUT_WR);
+
+	/* while until the pending data is completely flushed, the later
+	 * disconnect will bypass/ignore/drop any pending data.
+	 */
+	for (i = 0; ; i += msec_sleep) {
+		if (ioctl(fd, SIOCOUTQ, &queued) < 0)
+			xerror("can't query out socket queue: %d", errno);
+
+		if (!queued)
+			break;
+
+		if (i > poll_timeout)
+			xerror("timeout while waiting for spool to complete");
+		usleep(msec_sleep * 1000);
+	}
+
+	memset(&empty, 0, sizeof(empty));
+	empty.ss_family = AF_UNSPEC;
+	if (connect(fd, (struct sockaddr *)&empty, addrlen) < 0)
+		xerror("can't disconnect: %d", errno);
+}
+
 int main_loop(void)
 {
-	int fd;
+	int fd, ret, fd_in = 0;
+	struct addrinfo *peer;
 
 	/* listener is ready. */
-	fd = sock_connect_mptcp(cfg_host, cfg_port, cfg_sock_proto);
+	fd = sock_connect_mptcp(cfg_host, cfg_port, cfg_sock_proto, &peer);
 	if (fd < 0)
 		return 2;
 
+again:
 	check_getpeername_connect(fd);
 
 	SOCK_TEST_TCPULP(fd, cfg_sock_proto);
@@ -1077,7 +1145,31 @@ int main_loop(void)
 	if (cfg_cmsg_types.cmsg_enabled)
 		apply_cmsg_types(fd, &cfg_cmsg_types);
 
-	return copyfd_io(0, fd, 1);
+	if (cfg_input) {
+		fd_in = open(cfg_input, O_RDONLY);
+		if (fd < 0)
+			xerror("can't open %s:%d", cfg_input, errno);
+	}
+
+	/* close the client socket open only if we are not going to reconnect */
+	ret = copyfd_io(fd_in, fd, 1, cfg_repeat == 1);
+	if (ret)
+		return ret;
+
+	if (--cfg_repeat > 0) {
+		xdisconnect(fd, peer->ai_addrlen);
+
+		/* the socket could be unblocking at this point, we need the
+		 * connect to be blocking
+		 */
+		set_nonblock(fd, false);
+		if (connect(fd, peer->ai_addr, peer->ai_addrlen))
+			xerror("can't reconnect: %d", errno);
+		if (cfg_input)
+			close(fd_in);
+		goto again;
+	}
+	return 0;
 }
 
 int parse_proto(const char *proto)
@@ -1162,7 +1254,7 @@ static void parse_opts(int argc, char **argv)
 {
 	int c;
 
-	while ((c = getopt(argc, argv, "6jr:lp:s:ht:T:m:S:R:w:M:P:c:o:")) != -1) {
+	while ((c = getopt(argc, argv, "6c:hi:I:jlm:M:o:p:P:r:R:s:S:t:T:w:")) != -1) {
 		switch (c) {
 		case 'j':
 			cfg_join = true;
@@ -1176,6 +1268,12 @@ static void parse_opts(int argc, char **argv)
 			if (cfg_do_w <= 0)
 				cfg_do_w = 50;
 			break;
+		case 'i':
+			cfg_input = optarg;
+			break;
+		case 'I':
+			cfg_repeat = atoi(optarg);
+			break;
 		case 'l':
 			listen_mode = true;
 			break;
diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
index ee28f82a6c89..cb5809b89081 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
@@ -7,6 +7,7 @@ optstring="S:R:d:e:l:r:h4cm:f:tC"
 ret=0
 sin=""
 sout=""
+cin_disconnect=""
 cin=""
 cout=""
 ksft_skip=4
@@ -24,6 +25,7 @@ options_log=true
 do_tcp=0
 checksum=false
 filesize=0
+connect_per_transfer=1
 
 if [ $tc_loss -eq 100 ];then
 	tc_loss=1%
@@ -127,6 +129,7 @@ TEST_COUNT=0
 
 cleanup()
 {
+	rm -f "$cin_disconnect" "$cout_disconnect"
 	rm -f "$cin" "$cout"
 	rm -f "$sin" "$sout"
 	rm -f "$capout"
@@ -149,6 +152,8 @@ sout=$(mktemp)
 cin=$(mktemp)
 cout=$(mktemp)
 capout=$(mktemp)
+cin_disconnect="$cin".disconnect
+cout_disconnect="$cout".disconnect
 trap cleanup EXIT
 
 for i in "$ns1" "$ns2" "$ns3" "$ns4";do
@@ -500,8 +505,8 @@ do_transfer()
 	cookies=${cookies##*=}
 
 	if [ ${cl_proto} = "MPTCP" ] && [ ${srv_proto} = "MPTCP" ]; then
-		expect_synrx=$((stat_synrx_last_l+1))
-		expect_ackrx=$((stat_ackrx_last_l+1))
+		expect_synrx=$((stat_synrx_last_l+$connect_per_transfer))
+		expect_ackrx=$((stat_ackrx_last_l+$connect_per_transfer))
 	fi
 
 	if [ ${stat_synrx_now_l} -lt ${expect_synrx} ]; then
@@ -738,6 +743,33 @@ run_tests_peekmode()
 	run_tests_lo "$ns1" "$ns1" dead:beef:1::1 1 "-P ${peekmode}"
 }
 
+run_tests_disconnect()
+{
+	local peekmode="$1"
+	local old_cin=$cin
+	local old_sin=$sin
+
+	cat $cin $cin $cin > "$cin".disconnect
+
+	# force do_transfer to cope with the multiple tranmissions
+	sin="$cin.disconnect"
+	sin_disconnect=$old_sin
+	cin="$cin.disconnect"
+	cin_disconnect="$old_cin"
+	connect_per_transfer=3
+
+	echo "INFO: disconnect"
+	run_tests_lo "$ns1" "$ns1" 10.0.1.1 1 "-I 3 -i $old_cin"
+	run_tests_lo "$ns1" "$ns1" dead:beef:1::1 1 "-I 3 -i $old_cin"
+
+	# restore previous status
+	cout=$old_cout
+	cout_disconnect="$cout".disconnect
+	cin=$old_cin
+	cin_disconnect="$cin".disconnect
+	connect_per_transfer=1
+}
+
 display_time()
 {
 	time_end=$(date +%s)
@@ -853,6 +885,9 @@ stop_if_error "Tests with peek mode have failed"
 # connect to ns4 ip address, ns2 should intercept/proxy
 run_test_transparent 10.0.3.1 "tproxy ipv4"
 run_test_transparent dead:beef:3::1 "tproxy ipv6"
+stop_if_error "Tests with tproxy have failed"
+
+run_tests_disconnect
 
 display_time
 exit $ret
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 7ef639a9d4a6..3165bd1a43cc 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -937,6 +937,22 @@ chk_link_usage()
 	fi
 }
 
+wait_for_tw()
+{
+	local timeout_ms=$((timeout_poll * 1000))
+	local time=0
+	local ns=$1
+
+	while [ $time -lt $timeout_ms ]; do
+		local cnt=$(ip netns exec $ns ss -t state time-wait |wc -l)
+
+		[ "$cnt" = 1 ] && return 1
+		time=$((time + 100))
+		sleep 0.1
+	done
+	return 1
+}
+
 subflows_tests()
 {
 	reset
@@ -994,6 +1010,61 @@ subflows_tests()
 	chk_join_nr "single subflow, dev" 1 1 1
 }
 
+subflows_error_tests()
+{
+	# If a single subflow is configured, and matches the MPC src
+	# address, no additional subflow should be created
+	reset
+	ip netns exec $ns1 ./pm_nl_ctl limits 0 1
+	ip netns exec $ns2 ./pm_nl_ctl limits 0 1
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.1.2 flags subflow
+	run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+	chk_join_nr "no MPC reuse with single endpoint" 0 0 0
+
+	# multiple subflows, with subflow creation error
+	reset
+	ip netns exec $ns1 ./pm_nl_ctl limits 0 2
+	ip netns exec $ns2 ./pm_nl_ctl limits 0 2
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags subflow
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.2.2 flags subflow
+	ip netns exec $ns1 iptables -A INPUT -s 10.0.3.2 -p tcp -j REJECT
+	run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+	chk_join_nr "multi subflows, with failing subflow" 1 1 1
+
+	# multiple subflows, with subflow timeout on MPJ
+	reset
+	ip netns exec $ns1 ./pm_nl_ctl limits 0 2
+	ip netns exec $ns2 ./pm_nl_ctl limits 0 2
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags subflow
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.2.2 flags subflow
+	ip netns exec $ns1 iptables -A INPUT -s 10.0.3.2 -p tcp -j DROP
+	run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
+	chk_join_nr "multi subflows, with subflow timeout" 1 1 1
+
+	# multiple subflows, check that the endpoint corresponding to
+	# closed subflow (due to reset) is not reused if additional
+	# subflows are added later
+	reset
+	ip netns exec $ns1 ./pm_nl_ctl limits 0 1
+	ip netns exec $ns2 ./pm_nl_ctl limits 0 1
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags subflow
+	ip netns exec $ns1 iptables -A INPUT -s 10.0.3.2 -p tcp -j REJECT
+	run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow &
+
+	# updates in the child shell do not have any effect here, we
+	# need to bump the test counter for the above case
+	TEST_COUNT=$((TEST_COUNT+1))
+
+	# mpj subflow will be in TW after the reset
+	wait_for_tw $ns2
+	ip netns exec $ns2 ./pm_nl_ctl add 10.0.2.2 flags subflow
+	wait
+
+	# additional subflow could be created only if the PM select
+	# the later endpoint, skipping the already used one
+	chk_join_nr "multi subflows, fair usage on close" 1 1 1
+}
+
 signal_address_tests()
 {
 	# add_address, unused
@@ -1071,7 +1142,10 @@ signal_address_tests()
 	ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags signal
 	ip netns exec $ns2 ./pm_nl_ctl add 10.0.4.2 flags signal
 	run_tests $ns1 $ns2 10.0.1.1
-	chk_add_nr 4 4
+
+	# the server will not signal the address terminating
+	# the MPC subflow
+	chk_add_nr 3 3
 }
 
 link_failure_tests()
@@ -1802,6 +1876,7 @@ fullmesh_tests()
 all_tests()
 {
 	subflows_tests
+	subflows_error_tests
 	signal_address_tests
 	link_failure_tests
 	add_addr_timeout_tests
@@ -1821,6 +1896,7 @@ usage()
 {
 	echo "mptcp_join usage:"
 	echo "  -f subflows_tests"
+	echo "  -e subflows_error_tests"
 	echo "  -s signal_address_tests"
 	echo "  -l link_failure_tests"
 	echo "  -t add_addr_timeout_tests"
@@ -1869,11 +1945,14 @@ if [ $do_all_tests -eq 1 ]; then
 	exit $ret
 fi
 
-while getopts 'fsltra64bpkdmchCS' opt; do
+while getopts 'fesltra64bpkdmchCS' opt; do
 	case $opt in
 		f)
 			subflows_tests
 			;;
+		e)
+			subflows_error_tests
+			;;
 		s)
 			signal_address_tests
 			;;