Series comparison

v7:
 - move evts_get_info into mptcp_lib.sh, update userspace_pm.sh with
   this helper too.
 - drop the last two cleanup patches, they'll be sent in another series.

v6:
 - add a new helper get_info_value, update chk_mptcp_info(),
   verify_listener_events() and pedit_action_pkts() too.
 - only patch 1, 2, 4 are changed, other patches are the same as v5.

v5:
 - update userspace_pm_add_addr/sf helpers.
 - add userspace_pm_rm_addr/sf helpers.
 - remove id 0 subflow or address will send MP_RST, add chk_rst_nr for
   them.
 - add two selftests cleanups using for-loop.

v4:
 - add evts_get_info and chk_subflows helpers.
 - split the selftests patch into three.

v3:
 - address Matt's comments in v2.

v2:
 - fix CI errors.

This patchset addresses #379 and #391, add the abilities to remove id 0
subflow and address for userspace PM. And a selftest.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/391

Geliang Tang (7):
  selftests: mptcp: add evts_get_info helper
  selftests: mptcp: update userspace pm test helpers
  selftests: mptcp: userspace pm remove id 0 subflow
  mptcp: userspace pm allow creating id 0 subflow
  selftests: mptcp: userspace pm create id 0 subflow
  mptcp: userspace pm remove id 0 address
  selftests: mptcp: userspace pm remove id 0 address

net/mptcp/pm_userspace.c                      |  40 +++-
 .../testing/selftests/net/mptcp/mptcp_join.sh | 204 ++++++++++++------
 .../testing/selftests/net/mptcp/mptcp_lib.sh  |  20 ++
 .../selftests/net/mptcp/userspace_pm.sh       |  96 ++++-----
 4 files changed, 235 insertions(+), 125 deletions(-)

-- 
2.35.3

This patch adds a new helper get_info_value(), using 'sed' command to
parse the value of the given item name in the line with the given keyword,
to make chk_mptcp_info() and pedit_action_pkts() more readable.

Also add another helper evts_get_info() to use get_info_value() to parse
the output of 'pm_nl_ctl events' command, to make all the userpsace pm
selftests more readable, both in mptcp_join.sh and userspace_pm.sh.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 19 ++--
 .../testing/selftests/net/mptcp/mptcp_lib.sh  | 10 +++
 .../selftests/net/mptcp/userspace_pm.sh       | 86 +++++++++----------
 3 files changed, 57 insertions(+), 58 deletions(-)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index XXXXXXX..XXXXXXX 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -XXX,XX +XXX,XX @@ chk_mptcp_info()
 
 	print_check "mptcp_info ${info1:0:8}=$exp1:$exp2"
 
-	cnt1=$(ss -N $ns1 -inmHM | grep "$info1:" |
-	       sed -n 's/.*$'"$info1"':$$[[:digit:]]*$.*$/\2/p;q')
-	cnt2=$(ss -N $ns2 -inmHM | grep "$info2:" |
-	       sed -n 's/.*$'"$info2"':$$[[:digit:]]*$.*$/\2/p;q')
+	cnt1=$(ss -N $ns1 -inmHM | mptcp_lib_get_info_value "$info1" "$info1")
+	cnt2=$(ss -N $ns2 -inmHM | mptcp_lib_get_info_value "$info2" "$info2")
 	# 'ss' only display active connections and counters that are not 0.
 	[ -z "$cnt1" ] && cnt1=0
 	[ -z "$cnt2" ] && cnt2=0
@@ -XXX,XX +XXX,XX @@ verify_listener_events()
 		return
 	fi
 
-	type=$(grep "type:$e_type," $evt | sed -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q')
-	family=$(grep "type:$e_type," $evt | sed -n 's/.*$family:$$[[:digit:]]*$.*$/\2/p;q')
-	sport=$(grep "type:$e_type," $evt | sed -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q')
+	type=$(mptcp_lib_evts_get_info type "$evt" "$e_type")
+	family=$(mptcp_lib_evts_get_info family "$evt" "$e_type")
+	sport=$(mptcp_lib_evts_get_info sport "$evt" "$e_type")
 	if [ $family ] && [ $family = $AF_INET6 ]; then
-		saddr=$(grep "type:$e_type," $evt | sed -n 's/.*$saddr6:$$[0-9a-f:.]*$.*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr6 "$evt" "$e_type")
 	else
-		saddr=$(grep "type:$e_type," $evt | sed -n 's/.*$saddr4:$$[0-9.]*$.*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr4 "$evt" "$e_type")
 	fi
 
 	if [ $type ] && [ $type = $e_type ] &&
@@ -XXX,XX +XXX,XX @@ fastclose_tests()
 pedit_action_pkts()
 {
 	tc -n $ns2 -j -s action show action pedit index 100 | \
-		grep "packets" | \
-		sed 's/.*"packets":$[0-9]\+$,.*/\1/'
+		mptcp_lib_get_info_value \"packets\" packets
 }
 
 fail_tests()
diff --git a/tools/testing/selftests/net/mptcp/mptcp_lib.sh b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
index XXXXXXX..XXXXXXX 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_lib.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_lib.sh
@@ -XXX,XX +XXX,XX @@ mptcp_lib_result_print_all_tap() {
 		printf "%s\n" "${subtest}"
 	done
 }
+
+# get the value of keyword $1 in the line marked by keyword $2
+mptcp_lib_get_info_value() {
+	grep "${2}" | sed -n 's/.*$'${1}':$$[0-9a-f:.]*$.*$/\2/p;q'
+}
+
+# $1: info name ; $2: evts_ns ; $3: event type
+mptcp_lib_evts_get_info() {
+	cat "${2}" | mptcp_lib_get_info_value "${1}" "^type:${3:-1},"
+}
diff --git a/tools/testing/selftests/net/mptcp/userspace_pm.sh b/tools/testing/selftests/net/mptcp/userspace_pm.sh
index XXXXXXX..XXXXXXX 100755
--- a/tools/testing/selftests/net/mptcp/userspace_pm.sh
+++ b/tools/testing/selftests/net/mptcp/userspace_pm.sh
@@ -XXX,XX +XXX,XX @@ make_connection()
 	local server_token
 	local server_serverside
 
-	client_token=$(sed --unbuffered -n 's/.*$token:$$[[:digit:]]*$.*$/\2/p;q' "$client_evts")
-	client_port=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$client_evts")
-	client_serverside=$(sed --unbuffered -n 's/.*$server_side:$$[[:digit:]]*$.*$/\2/p;q'\
-				      "$client_evts")
-	server_token=$(grep "type:1," "$server_evts" |
-		       sed --unbuffered -n 's/.*$token:$$[[:digit:]]*$.*$/\2/p;q')
-	server_serverside=$(grep "type:1," "$server_evts" |
-			    sed --unbuffered -n 's/.*$server_side:$$[[:digit:]]*$.*$/\2/p;q')
+	client_token=$(mptcp_lib_evts_get_info token "$client_evts")
+	client_port=$(mptcp_lib_evts_get_info sport "$client_evts")
+	client_serverside=$(mptcp_lib_evts_get_info server_side "$client_evts")
+	server_token=$(mptcp_lib_evts_get_info token "$server_evts")
+	server_serverside=$(mptcp_lib_evts_get_info server_side "$server_evts")
 
 	print_test "Established IP${is_v6} MPTCP Connection ns2 => ns1"
 	if [ "$client_token" != "" ] && [ "$server_token" != "" ] && [ "$client_serverside" = 0 ] &&
@@ -XXX,XX +XXX,XX @@ verify_announce_event()
 	local dport
 	local id
 
-	type=$(sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	token=$(sed --unbuffered -n 's/.*$token:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
+	type=$(mptcp_lib_evts_get_info type "$evt" $e_type)
+	token=$(mptcp_lib_evts_get_info token "$evt" $e_type)
 	if [ "$e_af" = "v6" ]
 	then
-		addr=$(sed --unbuffered -n 's/.*$daddr6:$$[0-9a-f:.]*$.*$/\2/p;q' "$evt")
+		addr=$(mptcp_lib_evts_get_info daddr6 "$evt" $e_type)
 	else
-		addr=$(sed --unbuffered -n 's/.*$daddr4:$$[0-9.]*$.*$/\2/p;q' "$evt")
+		addr=$(mptcp_lib_evts_get_info daddr4 "$evt" $e_type)
 	fi
-	dport=$(sed --unbuffered -n 's/.*$dport:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	id=$(sed --unbuffered -n 's/.*$rem_id:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
+	dport=$(mptcp_lib_evts_get_info dport "$evt" $e_type)
+	id=$(mptcp_lib_evts_get_info rem_id "$evt" $e_type)
 
 	check_expected "type" "token" "addr" "dport" "id"
 }
@@ -XXX,XX +XXX,XX @@ test_announce()
 	   $client_addr_id dev ns2eth1 > /dev/null 2>&1
 
 	local type
-	type=$(sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q' "$server_evts")
+	type=$(mptcp_lib_evts_get_info type "$server_evts")
 	print_test "ADD_ADDR 10.0.2.2 (ns2) => ns1, invalid token"
 	if [ "$type" = "" ]
 	then
@@ -XXX,XX +XXX,XX @@ verify_remove_event()
 	local token
 	local id
 
-	type=$(sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	token=$(sed --unbuffered -n 's/.*$token:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	id=$(sed --unbuffered -n 's/.*$rem_id:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
+	type=$(mptcp_lib_evts_get_info type "$evt" $e_type)
+	token=$(mptcp_lib_evts_get_info token "$evt" $e_type)
+	id=$(mptcp_lib_evts_get_info rem_id "$evt" $e_type)
 
 	check_expected "type" "token" "id"
 }
@@ -XXX,XX +XXX,XX @@ test_remove()
 	   $client_addr_id > /dev/null 2>&1
 	print_test "RM_ADDR id:${client_addr_id} ns2 => ns1, invalid token"
 	local type
-	type=$(sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q' "$server_evts")
+	type=$(mptcp_lib_evts_get_info type "$server_evts")
 	if [ "$type" = "" ]
 	then
 		test_pass
@@ -XXX,XX +XXX,XX @@ test_remove()
 	ip netns exec "$ns2" ./pm_nl_ctl rem token "$client4_token" id\
 	   $invalid_id > /dev/null 2>&1
 	print_test "RM_ADDR id:${invalid_id} ns2 => ns1, invalid id"
-	type=$(sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q' "$server_evts")
+	type=$(mptcp_lib_evts_get_info type "$server_evts")
 	if [ "$type" = "" ]
 	then
 		test_pass
@@ -XXX,XX +XXX,XX @@ verify_subflow_events()
 		fi
 	fi
 
-	type=$(sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	token=$(sed --unbuffered -n 's/.*$token:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	family=$(sed --unbuffered -n 's/.*$family:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	dport=$(sed --unbuffered -n 's/.*$dport:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	locid=$(sed --unbuffered -n 's/.*$loc_id:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
-	remid=$(sed --unbuffered -n 's/.*$rem_id:$$[[:digit:]]*$.*$/\2/p;q' "$evt")
+	type=$(mptcp_lib_evts_get_info type "$evt" $e_type)
+	token=$(mptcp_lib_evts_get_info token "$evt" $e_type)
+	family=$(mptcp_lib_evts_get_info family "$evt" $e_type)
+	dport=$(mptcp_lib_evts_get_info dport "$evt" $e_type)
+	locid=$(mptcp_lib_evts_get_info loc_id "$evt" $e_type)
+	remid=$(mptcp_lib_evts_get_info rem_id "$evt" $e_type)
 	if [ "$family" = "$AF_INET6" ]
 	then
-		saddr=$(sed --unbuffered -n 's/.*$saddr6:$$[0-9a-f:.]*$.*$/\2/p;q' "$evt")
-		daddr=$(sed --unbuffered -n 's/.*$daddr6:$$[0-9a-f:.]*$.*$/\2/p;q' "$evt")
+		saddr=$(mptcp_lib_evts_get_info saddr6 "$evt" $e_type)
+		daddr=$(mptcp_lib_evts_get_info daddr6 "$evt" $e_type)
 	else
-		saddr=$(sed --unbuffered -n 's/.*$saddr4:$$[0-9.]*$.*$/\2/p;q' "$evt")
-		daddr=$(sed --unbuffered -n 's/.*$daddr4:$$[0-9.]*$.*$/\2/p;q' "$evt")
+		saddr=$(mptcp_lib_evts_get_info saddr4 "$evt" $e_type)
+		daddr=$(mptcp_lib_evts_get_info daddr4 "$evt" $e_type)
 	fi
 
 	check_expected "type" "token" "daddr" "dport" "family" "saddr" "locid" "remid"
@@ -XXX,XX +XXX,XX @@ test_subflows()
 	kill_wait $listener_pid
 
 	local sport
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$server_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$server_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from server to client machine
 	:>"$server_evts"
@@ -XXX,XX +XXX,XX @@ test_subflows()
 	# Delete the listener from the client ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$server_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$server_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW6 from server to client machine
 	:>"$server_evts"
@@ -XXX,XX +XXX,XX @@ test_subflows()
 	# Delete the listener from the client ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$server_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$server_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from server to client machine
 	:>"$server_evts"
@@ -XXX,XX +XXX,XX @@ test_subflows()
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from client to server machine
 	:>"$client_evts"
@@ -XXX,XX +XXX,XX @@ test_subflows()
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW6 from client to server machine
 	:>"$client_evts"
@@ -XXX,XX +XXX,XX @@ test_subflows()
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from client to server machine
 	:>"$client_evts"
@@ -XXX,XX +XXX,XX @@ test_subflows_v4_v6_mix()
 	# Delete the listener from the server ns, if one was created
 	kill_wait $listener_pid
 
-	sport=$(sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q' "$client_evts")
+	sport=$(mptcp_lib_evts_get_info sport "$client_evts" $SUB_ESTABLISHED)
 
 	# DESTROY_SUBFLOW from client to server machine
 	:>"$client_evts"
@@ -XXX,XX +XXX,XX @@ verify_listener_events()
 		print_test "CLOSE_LISTENER $e_saddr:$e_sport"
 	fi
 
-	type=$(grep "type:$e_type," $evt |
-	       sed --unbuffered -n 's/.*$type:$$[[:digit:]]*$.*$/\2/p;q')
-	family=$(grep "type:$e_type," $evt |
-		 sed --unbuffered -n 's/.*$family:$$[[:digit:]]*$.*$/\2/p;q')
-	sport=$(grep "type:$e_type," $evt |
-		sed --unbuffered -n 's/.*$sport:$$[[:digit:]]*$.*$/\2/p;q')
+	type=$(mptcp_lib_evts_get_info type $evt $e_type)
+	family=$(mptcp_lib_evts_get_info family $evt $e_type)
+	sport=$(mptcp_lib_evts_get_info sport $evt $e_type)
 	if [ $family ] && [ $family = $AF_INET6 ]; then
-		saddr=$(grep "type:$e_type," $evt |
-			sed --unbuffered -n 's/.*$saddr6:$$[0-9a-f:.]*$.*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr6 $evt $e_type)
 	else
-		saddr=$(grep "type:$e_type," $evt |
-			sed --unbuffered -n 's/.*$saddr4:$$[0-9.]*$.*$/\2/p;q')
+		saddr=$(mptcp_lib_evts_get_info saddr4 $evt $e_type)
 	fi
 
 	check_expected "type" "family" "saddr" "sport"
-- 
2.35.3

This patch adds a new argument namespace to userspace_pm_add_addr() and
userspace_pm_add_sf() to make these two helper more versatile.

Add two more versatile helpers for userspace pm remove subflow or address:
userspace_pm_rm_addr() and userspace_pm_rm_sf(). The original test helpers
userspace_pm_rm_sf_addr_ns1() and userspace_pm_rm_sf_addr_ns2() can be
replaced by these new helpers.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 95 +++++++++----------
 .../testing/selftests/net/mptcp/mptcp_lib.sh  | 10 ++
 .../selftests/net/mptcp/userspace_pm.sh       | 10 --
 3 files changed, 54 insertions(+), 61 deletions(-)

This patch adds a selftest for userpsace PM to remove id 0 subflow. Use
userspace_pm_add_sf() to add a subflow, and pass initial ip address to
userspace_pm_rm_sf() to remove id 0 subflow.

Add a new helper chk_all_subflows(), in it use 'ss' command

ss -ti | grep -c tcp-ulp-mptcp

to get the "correct" amount of subflows, including the initial
subflow.

When closing the initial subflow in __mptcp_close_ssk(), dispose_it is
false, then tcp_disconnect is invoked. This will send a MP_RST to close
a subflow on the peer too. So chk_rst_nr() is added in this test, and
chk_all_subflows after closing the initial subflow is '1 1', not '2 1'.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)

This patch drops id 0 limitation in mptcp_nl_cmd_sf_create() to allow
creating additional subflows with the local addr ID 0.

There is no reason not to allow additional subflows from this local
address: we should be able to create new subflows from the initial
endpoint. This limitation was breaking fullmesh support from userspace.

Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/391
Suggested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 net/mptcp/pm_userspace.c | 6 ------
 1 file changed, 6 deletions(-)

This patch adds a selftest to create id 0 subflow. Pass id 0 to the
helper userspace_pm_add_sf() to create id 0 subflow. chk_mptcp_info
shows one subflow but chk_all_subflows shows two subflows in each
namespace.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

This patch adds the ability to send RM_ADDR for local ID 0. Check
whether id 0 address is removed, if not, put id 0 into a removing
list, pass it to mptcp_pm_remove_addr() to remove id 0 address.

There is no reason not to allow the userspace to remove the initial
address (ID 0). This special case was not taken into account not
letting the userspace to delete all addresses as announced.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379
Fixes: d9a4594edabf ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE")
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 net/mptcp/pm_userspace.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -XXX,XX +XXX,XX @@ int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static int mptcp_userspace_remove_id_zero_address(struct mptcp_sock *msk,
+						  struct genl_info *info)
+{
+	struct mptcp_rm_list list = { .nr = 0 };
+	struct mptcp_subflow_context *subflow;
+	bool has_id_0 = false;
+	int err = -EINVAL;
+
+	lock_sock((struct sock *)msk);
+	spin_lock_bh(&msk->pm.lock);
+	mptcp_for_each_subflow(msk, subflow) {
+		if (subflow->remote_id == 0) {
+			has_id_0 = true;
+			break;
+		}
+	}
+	if (!has_id_0) {
+		GENL_SET_ERR_MSG(info, "address with id 0 not found");
+		goto out;
+	}
+
+	list.ids[list.nr++] = 0;
+	mptcp_pm_remove_addr(msk, &list);
+	err = 0;
+out:
+	spin_unlock_bh(&msk->pm.lock);
+	release_sock((struct sock *)msk);
+	sock_put((struct sock *)msk);
+	return err;
+}
+
 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
 {
 	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
@@ -XXX,XX +XXX,XX @@ int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
 		goto remove_err;
 	}
 
+	if (id_val == 0)
+		return mptcp_userspace_remove_id_zero_address(msk, info);
+
 	lock_sock((struct sock *)msk);
 
 	list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
-- 
2.35.3

This patch adds a selftest for userpsace PM to remove id 0 address.
Use userspace_pm_add_addr() helper to add a id 10 address, then use
userspace_pm_rm_addr() helper to remove id 0 address.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)

v9:
 - update __mptcp_check_initial_subflow().
 - split the code that relies on the 'ss' modification into patch 9.

v8:
 - merge two squash-to patches for v7.
 - address to #428 too.

v7:
 - move evts_get_info into mptcp_lib.sh, update userspace_pm.sh with
   this helper too.
 - drop the last two cleanup patches, they'll be sent in another series.

v6:
 - add a new helper get_info_value, update chk_mptcp_info(),
   verify_listener_events() and pedit_action_pkts() too.
 - only patch 1, 2, 4 are changed, other patches are the same as v5.

v4:
 - add evts_get_info and chk_subflows helpers.
 - split the selftests patch into three.

v3:
 - address Matt's comments in v2.

v2:
 - fix CI errors.

This patchset addresses #379 and #391, add the abilities to remove id 0
subflow and address for userspace PM. And a selftest.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/391
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/428

Geliang Tang (9):
  selftests: mptcp: add evts_get_info helper
  selftests: mptcp: update userspace pm test helpers
  selftests: mptcp: userspace pm remove id 0 subflow
  mptcp: userspace pm allow creating id 0 subflow
  selftests: mptcp: userspace pm create id 0 subflow
  mptcp: add no_initial_subflow mptcpi_flags
  mptcp: userspace pm remove id 0 address
  selftests: mptcp: userspace pm remove id 0 address
  selftests: mptcp: check no_initial_subflow flag

-- 
2.35.3

This patch adds a new argument namespace to userspace_pm_add_addr() and
userspace_pm_add_sf() to make these two helper more versatile.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 89 +++++++++----------
 .../testing/selftests/net/mptcp/mptcp_lib.sh  |  2 +
 .../selftests/net/mptcp/userspace_pm.sh       |  1 -
 3 files changed, 46 insertions(+), 46 deletions(-)

This patch adds a selftest for userpsace PM to remove id 0 subflow. Use
userspace_pm_add_sf() to add a subflow, and pass initial ip address to
userspace_pm_rm_sf() to remove id 0 subflow.

Add a new helper chk_all_subflows(), in it use 'ss' command

ss -ti | grep -c tcp-ulp-mptcp

to get the "correct" amount of subflows, including the initial one.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 47 +++++++++++++++++++
 1 file changed, 47 insertions(+)

This patch drops id 0 limitation in mptcp_nl_cmd_sf_create() to allow
creating additional subflows with the local addr ID 0.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

If the initial subflow has been removed, we cannot know without checking
other counters, e.g. ss -ti <filter> | grep -c tcp-ulp-mptcp or
getsockopt(SOL_MPTCP, MPTCP_FULL_INFO, ...) (or others except MPTCP_INFO
of course) and then check mptcp_subflow_data->num_subflows to get the
total amount of subflows.

This patch adds a new flag NO_INITIAL_SUBFLOW in mptcpi_flags to know if
the initial subflow has been removed.

Add a new helper __mptcp_check_initial_subflow() to check whether the
initial subflow is closing or closed.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/428
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 include/uapi/linux/mptcp.h | 1 +
 net/mptcp/pm_netlink.c     | 3 ++-
 net/mptcp/protocol.h       | 5 +++++
 net/mptcp/sockopt.c        | 2 ++
 4 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index XXXXXXX..XXXXXXX 100644
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -XXX,XX +XXX,XX @@ enum {
 
 #define MPTCP_INFO_FLAG_FALLBACK		_BITUL(0)
 #define MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED	_BITUL(1)
+#define MPTCP_INFO_FLAG_NO_INITIAL_SUBFLOW	_BITUL(2)
 
 struct mptcp_info {
 	__u8	mptcpi_subflows;
diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_remove_id_zero_address(struct net *net,
 		struct sock *sk = (struct sock *)msk;
 		struct mptcp_addr_info msk_local;
 
-		if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk))
+		if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk) ||
+		    !__mptcp_check_initial_subflow(msk))
 			goto next;
 
 		mptcp_local_address((struct sock_common *)msk, &msk_local);
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -XXX,XX +XXX,XX @@ static inline void __mptcp_do_fallback(struct mptcp_sock *msk)
 	set_bit(MPTCP_FALLBACK_DONE, &msk->flags);
 }
 
+static inline bool __mptcp_check_initial_subflow(const struct mptcp_sock *msk)
+{
+	return msk->first && inet_sk_state_load(msk->first) != TCP_CLOSE;
+}
+
 static inline void mptcp_do_fallback(struct sock *ssk)
 {
 	struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -XXX,XX +XXX,XX @@ void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
 		flags |= MPTCP_INFO_FLAG_FALLBACK;
 	if (READ_ONCE(msk->can_ack))
 		flags |= MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED;
+	if (!__mptcp_check_initial_subflow(msk))
+		flags |= MPTCP_INFO_FLAG_NO_INITIAL_SUBFLOW;
 	info->mptcpi_flags = flags;
 	mptcp_data_lock(sk);
 	info->mptcpi_snd_una = msk->snd_una;
-- 
2.35.3

This patch adds the ability to send RM_ADDR for local ID 0. Check
whether id 0 address is removed, if not, put id 0 into a removing
list, pass it to mptcp_pm_remove_addr() to remove id 0 address.

There is no reason not to allow the userspace to remove the initial
address (ID 0). This special case was not taken into account not
letting the userspace to delete all addresses as announced.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/379
Fixes: d9a4594edabf ("mptcp: netlink: Add MPTCP_PM_CMD_REMOVE")
Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 net/mptcp/pm_userspace.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -XXX,XX +XXX,XX @@ int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static int mptcp_userspace_remove_id_zero_address(struct mptcp_sock *msk,
+						  struct genl_info *info)
+{
+	struct mptcp_rm_list list = { .nr = 0 };
+	struct sock *sk = (struct sock *)msk;
+	int err = -EINVAL;
+
+	lock_sock(sk);
+	spin_lock_bh(&msk->pm.lock);
+	if (!__mptcp_check_initial_subflow(msk)) {
+		GENL_SET_ERR_MSG(info, "address with id 0 not found");
+		goto out;
+	}
+
+	list.ids[list.nr++] = 0;
+	mptcp_pm_remove_addr(msk, &list);
+	err = 0;
+out:
+	spin_unlock_bh(&msk->pm.lock);
+	release_sock(sk);
+	sock_put(sk);
+	return err;
+}
+
 int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
 {
 	struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN];
@@ -XXX,XX +XXX,XX @@ int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info)
 		goto remove_err;
 	}
 
+	if (id_val == 0)
+		return mptcp_userspace_remove_id_zero_address(msk, info);
+
 	lock_sock((struct sock *)msk);
 
 	list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) {
-- 
2.35.3

This patch adds a selftest for userpsace PM to remove id 0 address.
Use userspace_pm_add_addr() helper to add a id 10 address, then use
userspace_pm_rm_addr() helper to remove id 0 address.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)

Add a new argument all for chk_mptcp_info() to get the "correct" amount
of subflows, including the initial one, if it's set as "all".

New version of ss will test the no_initial_subflow flag to count number
of all subflows.

With this new flag, we can then compute the total amount of subflows
from mptcp_info by doing something like:

if (mptcpi_flags & MPTCP_INFO_FLAG_HAS_INITIAL_SUBFLOW)
          mptcpi_subflows += 1;

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 23 ++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)