[PATCH net 0/4] mptcp: various fixes

[PATCH net 0/4] mptcp: various fixes

[Matthieu Baerts (NGI0)]

The different patches here are some unrelated fixes for MPTCP:

- Patch 1 ensures 'snd_una' is initialised on connect in case of MPTCP
  fallback to TCP followed by retransmissions before the processing of
  any other incoming packets. A fix for v5.9+.

- Patch 2 makes sure the RmAddr MIB counter is incremented, and only
  once per ID, upon the reception of a RM_ADDR. A fix for v5.10+.

- Patch 3 doesn't update 'add addr' related counters if the connect()
  was not possible. A fix for v5.7+.

- Patch 4 updates the mailmap file to add Geliang's new email address.

Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
Geliang Tang (1):
      mailmap: map Geliang's new email address

Paolo Abeni (1):
      mptcp: ensure snd_una is properly initialized on connect

YonglongLi (2):
      mptcp: pm: inc RmAddr MIB counter once per RM_ADDR ID
      mptcp: pm: update add_addr counters after connect

 .mailmap                                        |  1 +
 net/mptcp/pm_netlink.c                          | 21 ++++++++++++++-------
 net/mptcp/protocol.c                            |  1 +
 tools/testing/selftests/net/mptcp/mptcp_join.sh |  5 +++--
 4 files changed, 19 insertions(+), 9 deletions(-)
---
base-commit: c44711b78608c98a3e6b49ce91678cd0917d5349
change-id: 20240607-upstream-net-20240607-misc-fixes-024007171d60

Best regards,
-- 
Matthieu Baerts (NGI0) <matttbe@kernel.org>

[PATCH net 1/4] mptcp: ensure snd_una is properly initialized on connect

[Matthieu Baerts (NGI0)]

From: Paolo Abeni <pabeni@redhat.com>

This is strictly related to commit fb7a0d334894 ("mptcp: ensure snd_nxt
is properly initialized on connect"). It turns out that syzkaller can
trigger the retransmit after fallback and before processing any other
incoming packet - so that snd_una is still left uninitialized.

Address the issue explicitly initializing snd_una together with snd_nxt
and write_seq.

Suggested-by: Mat Martineau <martineau@kernel.org>
Fixes: 8fd738049ac3 ("mptcp: fallback in case of simultaneous connect")
Cc: stable@vger.kernel.org
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/485
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/protocol.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 96b113854bd3..bb7dca8aa2d9 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -3740,6 +3740,7 @@ static int mptcp_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 
 	WRITE_ONCE(msk->write_seq, subflow->idsn);
 	WRITE_ONCE(msk->snd_nxt, subflow->idsn);
+	WRITE_ONCE(msk->snd_una, subflow->idsn);
 	if (likely(!__mptcp_check_fallback(msk)))
 		MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEACTIVE);
 

-- 
2.43.0

[PATCH net 2/4] mptcp: pm: inc RmAddr MIB counter once per RM_ADDR ID

[Matthieu Baerts (NGI0)]

From: YonglongLi <liyonglong@chinatelecom.cn>

The RmAddr MIB counter is supposed to be incremented once when a valid
RM_ADDR has been received. Before this patch, it could have been
incremented as many times as the number of subflows connected to the
linked address ID, so it could have been 0, 1 or more than 1.

The "RmSubflow" is incremented after a local operation. In this case,
it is normal to tied it with the number of subflows that have been
actually removed.

The "remove invalid addresses" MP Join subtest has been modified to
validate this case. A broadcast IP address is now used instead: the
client will not be able to create a subflow to this address. The
consequence is that when receiving the RM_ADDR with the ID attached to
this broadcast IP address, no subflow linked to this ID will be found.

Fixes: 7a7e52e38a40 ("mptcp: add RM_ADDR related mibs")
Cc: stable@vger.kernel.org
Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: YonglongLi <liyonglong@chinatelecom.cn>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/pm_netlink.c                          | 5 ++++-
 tools/testing/selftests/net/mptcp/mptcp_join.sh | 3 ++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 7f53e022e27e..766a8409fa67 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -814,10 +814,13 @@ static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
 			spin_lock_bh(&msk->pm.lock);
 
 			removed = true;
-			__MPTCP_INC_STATS(sock_net(sk), rm_type);
+			if (rm_type == MPTCP_MIB_RMSUBFLOW)
+				__MPTCP_INC_STATS(sock_net(sk), rm_type);
 		}
 		if (rm_type == MPTCP_MIB_RMSUBFLOW)
 			__set_bit(rm_id ? rm_id : msk->mpc_endpoint_id, msk->pm.id_avail_bitmap);
+		else if (rm_type == MPTCP_MIB_RMADDR)
+			__MPTCP_INC_STATS(sock_net(sk), rm_type);
 		if (!removed)
 			continue;
 
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 2b66c5fa71eb..aea314d140c9 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -2250,7 +2250,8 @@ remove_tests()
 		pm_nl_set_limits $ns1 3 3
 		pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
 		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
-		pm_nl_add_endpoint $ns1 10.0.14.1 flags signal
+		# broadcast IP: no packet for this address will be received on ns1
+		pm_nl_add_endpoint $ns1 224.0.0.1 flags signal
 		pm_nl_set_limits $ns2 3 3
 		addr_nr_ns1=-3 speed=10 \
 			run_tests $ns1 $ns2 10.0.1.1

-- 
2.43.0

[PATCH net 3/4] mptcp: pm: update add_addr counters after connect

[Matthieu Baerts (NGI0)]

From: YonglongLi <liyonglong@chinatelecom.cn>

The creation of new subflows can fail for different reasons. If no
subflow have been created using the received ADD_ADDR, the related
counters should not be updated, otherwise they will never be decremented
for events related to this ID later on.

For the moment, the number of accepted ADD_ADDR is only decremented upon
the reception of a related RM_ADDR, and only if the remote address ID is
currently being used by at least one subflow. In other words, if no
subflow can be created with the received address, the counter will not
be decremented. In this case, it is then important not to increment
pm.add_addr_accepted counter, and not to modify pm.accept_addr bit.

Note that this patch does not modify the behaviour in case of failures
later on, e.g. if the MP Join is dropped or rejected.

The "remove invalid addresses" MP Join subtest has been modified to
validate this case. The broadcast IP address is added before the "valid"
address that will be used to successfully create a subflow, and the
limit is decreased by one: without this patch, it was not possible to
create the last subflow, because:

- the broadcast address would have been accepted even if it was not
  usable: the creation of a subflow to this address results in an error,

- the limit of 2 accepted ADD_ADDR would have then been reached.

Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable@vger.kernel.org
Co-developed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: YonglongLi <liyonglong@chinatelecom.cn>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/pm_netlink.c                          | 16 ++++++++++------
 tools/testing/selftests/net/mptcp/mptcp_join.sh |  4 ++--
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 766a8409fa67..ea9e5817b9e9 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -677,6 +677,7 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 	unsigned int add_addr_accept_max;
 	struct mptcp_addr_info remote;
 	unsigned int subflows_max;
+	bool sf_created = false;
 	int i, nr;
 
 	add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
@@ -704,15 +705,18 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 	if (nr == 0)
 		return;
 
-	msk->pm.add_addr_accepted++;
-	if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
-	    msk->pm.subflows >= subflows_max)
-		WRITE_ONCE(msk->pm.accept_addr, false);
-
 	spin_unlock_bh(&msk->pm.lock);
 	for (i = 0; i < nr; i++)
-		__mptcp_subflow_connect(sk, &addrs[i], &remote);
+		if (__mptcp_subflow_connect(sk, &addrs[i], &remote) == 0)
+			sf_created = true;
 	spin_lock_bh(&msk->pm.lock);
+
+	if (sf_created) {
+		msk->pm.add_addr_accepted++;
+		if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
+		    msk->pm.subflows >= subflows_max)
+			WRITE_ONCE(msk->pm.accept_addr, false);
+	}
 }
 
 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index aea314d140c9..108aeeb84ef1 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -2249,10 +2249,10 @@ remove_tests()
 	if reset "remove invalid addresses"; then
 		pm_nl_set_limits $ns1 3 3
 		pm_nl_add_endpoint $ns1 10.0.12.1 flags signal
-		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
 		# broadcast IP: no packet for this address will be received on ns1
 		pm_nl_add_endpoint $ns1 224.0.0.1 flags signal
-		pm_nl_set_limits $ns2 3 3
+		pm_nl_add_endpoint $ns1 10.0.3.1 flags signal
+		pm_nl_set_limits $ns2 2 2
 		addr_nr_ns1=-3 speed=10 \
 			run_tests $ns1 $ns2 10.0.1.1
 		chk_join_nr 1 1 1

-- 
2.43.0

[PATCH net 4/4] mailmap: map Geliang's new email address

[Matthieu Baerts (NGI0)]

From: Geliang Tang <geliang@kernel.org>

Just like my other email addresses, map my new one to kernel.org
account too.

My new email address uses "last name, first name" format, which is
different from my other email addresses. This mailmap is also used
to indicate that it is actually the same person.

Suggested-by: Mat Martineau <martineau@kernel.org>
Suggested-by: Matthieu Baerts <matttbe@kernel.org>
Signed-off-by: Geliang Tang <geliang@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 .mailmap | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.mailmap b/.mailmap
index efd9fa867a8e..9af91bd3584b 100644
--- a/.mailmap
+++ b/.mailmap
@@ -217,6 +217,7 @@ Geliang Tang <geliang@kernel.org> <geliang.tang@suse.com>
 Geliang Tang <geliang@kernel.org> <geliangtang@xiaomi.com>
 Geliang Tang <geliang@kernel.org> <geliangtang@gmail.com>
 Geliang Tang <geliang@kernel.org> <geliangtang@163.com>
+Geliang Tang <geliang@kernel.org> <tanggeliang@kylinos.cn>
 Georgi Djakov <djakov@kernel.org> <georgi.djakov@linaro.org>
 Gerald Schaefer <gerald.schaefer@linux.ibm.com> <geraldsc@de.ibm.com>
 Gerald Schaefer <gerald.schaefer@linux.ibm.com> <gerald.schaefer@de.ibm.com>

-- 
2.43.0

Re: [PATCH net 0/4] mptcp: various fixes

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Fri, 07 Jun 2024 17:01:47 +0200 you wrote:
> The different patches here are some unrelated fixes for MPTCP:
> 
> - Patch 1 ensures 'snd_una' is initialised on connect in case of MPTCP
>   fallback to TCP followed by retransmissions before the processing of
>   any other incoming packets. A fix for v5.9+.
> 
> - Patch 2 makes sure the RmAddr MIB counter is incremented, and only
>   once per ID, upon the reception of a RM_ADDR. A fix for v5.10+.
> 
> [...]

Here is the summary with links:
  - [net,1/4] mptcp: ensure snd_una is properly initialized on connect
    https://git.kernel.org/netdev/net/c/8031b58c3a9b
  - [net,2/4] mptcp: pm: inc RmAddr MIB counter once per RM_ADDR ID
    https://git.kernel.org/netdev/net/c/6a09788c1a66
  - [net,3/4] mptcp: pm: update add_addr counters after connect
    https://git.kernel.org/netdev/net/c/40eec1795cc2
  - [net,4/4] mailmap: map Geliang's new email address
    https://git.kernel.org/netdev/net/c/74acb250e103

You are awesome, thank you!
-- 
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