--- /dev/null
+From stable+bounces-66732-greg=kroah.com@vger.kernel.org Mon Aug 12 17:03:00 2024
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+Date: Mon, 12 Aug 2024 17:02:17 +0200
+Subject: mptcp: pm: do not ignore 'subflow' if 'signal' flag is also set
+To: mptcp@lists.linux.dev, stable@vger.kernel.org, gregkh@linuxfoundation.org
+Cc: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>, Paolo Abeni <pabeni@redhat.com>, Mat Martineau <martineau@kernel.org>, Jakub Kicinski <kuba@kernel.org>
+Message-ID: <20240812150213.489098-10-matttbe@kernel.org>
+
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+
+commit 85df533a787bf07bf4367ce2a02b822ff1fba1a3 upstream.
+
+Up to the 'Fixes' commit, having an endpoint with both the 'signal' and
+'subflow' flags, resulted in the creation of a subflow and an address
+announcement using the address linked to this endpoint. After this
+commit, only the address announcement was done, ignoring the 'subflow'
+flag.
+
+That's because the same bitmap is used for the two flags. It is OK to
+keep this single bitmap, the already selected local endpoint simply have
+to be re-used, but not via select_local_address() not to look at the
+just modified bitmap.
+
+Note that it is unusual to set the two flags together: creating a new
+subflow using a new local address will implicitly advertise it to the
+other peer. So in theory, no need to advertise it explicitly as well.
+Maybe there are use-cases -- the subflow might not reach the other peer
+that way, we can ask the other peer to try initiating the new subflow
+without delay -- or very likely the user is confused, and put both flags
+"just to be sure at least the right one is set". Still, if it is
+allowed, the kernel should do what has been asked: using this endpoint
+to announce the address and to create a new subflow from it.
+
+An alternative is to forbid the use of the two flags together, but
+that's probably too late, there are maybe use-cases, and it was working
+before. This patch will avoid people complaining subflows are not
+created using the endpoint they added with the 'subflow' and 'signal'
+flag.
+
+Note that with the current patch, the subflow might not be created in
+some corner cases, e.g. if the 'subflows' limit was reached when sending
+the ADD_ADDR, but changed later on. It is probably not worth splitting
+id_avail_bitmap per target ('signal', 'subflow'), which will add another
+large field to the msk "just" to track (again) endpoints. Anyway,
+currently when the limits are changed, the kernel doesn't check if new
+subflows can be created or removed, because we would need to keep track
+of the received ADD_ADDR, and more. It sounds OK to assume that the
+limits should be properly configured before establishing new
+connections.
+
+Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk")
+Cc: stable@vger.kernel.org
+Suggested-by: Paolo Abeni <pabeni@redhat.com>
+Reviewed-by: Mat Martineau <martineau@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-5-c8a9b036493b@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/mptcp/pm_netlink.c | 16 ++++++++++++----
+ 1 file changed, 12 insertions(+), 4 deletions(-)
+
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -512,8 +512,8 @@ __lookup_addr(struct pm_nl_pernet *perne
+
+ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
+ {
++ struct mptcp_pm_addr_entry *local, *signal_and_subflow = NULL;
+ struct sock *sk = (struct sock *)msk;
+- struct mptcp_pm_addr_entry *local;
+ unsigned int add_addr_signal_max;
+ unsigned int local_addr_max;
+ struct pm_nl_pernet *pernet;
+@@ -579,6 +579,9 @@ static void mptcp_pm_create_subflow_or_s
+ msk->pm.add_addr_signaled++;
+ mptcp_pm_announce_addr(msk, &local->addr, false);
+ mptcp_pm_nl_addr_send_ack(msk);
++
++ if (local->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW)
++ signal_and_subflow = local;
+ }
+
+ subflow:
+@@ -589,9 +592,14 @@ subflow:
+ bool fullmesh;
+ int i, nr;
+
+- local = select_local_address(pernet, msk);
+- if (!local)
+- break;
++ if (signal_and_subflow) {
++ local = signal_and_subflow;
++ signal_and_subflow = NULL;
++ } else {
++ local = select_local_address(pernet, msk);
++ if (!local)
++ break;
++ }
+
+ fullmesh = !!(local->flags & MPTCP_PM_ADDR_FLAG_FULLMESH);
+
--- /dev/null
+From stable+bounces-66731-greg=kroah.com@vger.kernel.org Mon Aug 12 17:03:18 2024
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+Date: Mon, 12 Aug 2024 17:02:16 +0200
+Subject: mptcp: pm: don't try to create sf if alloc failed
+To: mptcp@lists.linux.dev, stable@vger.kernel.org, gregkh@linuxfoundation.org
+Cc: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>, Paolo Abeni <pabeni@redhat.com>, Mat Martineau <martineau@kernel.org>, Jakub Kicinski <kuba@kernel.org>
+Message-ID: <20240812150213.489098-9-matttbe@kernel.org>
+
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+
+commit cd7c957f936f8cb80d03e5152f4013aae65bd986 upstream.
+
+It sounds better to avoid wasting cycles and / or put extreme memory
+pressure on the system by trying to create new subflows if it was not
+possible to add a new item in the announce list.
+
+While at it, a warning is now printed if the entry was already in the
+list as it should not happen with the in-kernel path-manager. With this
+PM, mptcp_pm_alloc_anno_list() should only fail in case of memory
+pressure.
+
+Fixes: b6c08380860b ("mptcp: remove addr and subflow in PM netlink")
+Cc: stable@vger.kernel.org
+Suggested-by: Paolo Abeni <pabeni@redhat.com>
+Reviewed-by: Mat Martineau <martineau@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-4-c8a9b036493b@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/mptcp/pm_netlink.c | 10 ++++++----
+ 1 file changed, 6 insertions(+), 4 deletions(-)
+
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -348,7 +348,7 @@ bool mptcp_pm_alloc_anno_list(struct mpt
+ add_entry = mptcp_lookup_anno_list_by_saddr(msk, addr);
+
+ if (add_entry) {
+- if (mptcp_pm_is_kernel(msk))
++ if (WARN_ON_ONCE(mptcp_pm_is_kernel(msk)))
+ return false;
+
+ sk_reset_timer(sk, &add_entry->add_timer,
+@@ -555,8 +555,6 @@ static void mptcp_pm_create_subflow_or_s
+
+ /* check first for announce */
+ if (msk->pm.add_addr_signaled < add_addr_signal_max) {
+- local = select_signal_address(pernet, msk);
+-
+ /* due to racing events on both ends we can reach here while
+ * previous add address is still running: if we invoke now
+ * mptcp_pm_announce_addr(), that will fail and the
+@@ -567,11 +565,15 @@ static void mptcp_pm_create_subflow_or_s
+ if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL))
+ return;
+
++ local = select_signal_address(pernet, msk);
+ if (!local)
+ goto subflow;
+
++ /* If the alloc fails, we are on memory pressure, not worth
++ * continuing, and trying to create subflows.
++ */
+ if (!mptcp_pm_alloc_anno_list(msk, &local->addr))
+- goto subflow;
++ return;
+
+ __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
+ msk->pm.add_addr_signaled++;
--- /dev/null
+From stable+bounces-66730-greg=kroah.com@vger.kernel.org Mon Aug 12 17:02:58 2024
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+Date: Mon, 12 Aug 2024 17:02:15 +0200
+Subject: mptcp: pm: reduce indentation blocks
+To: mptcp@lists.linux.dev, stable@vger.kernel.org, gregkh@linuxfoundation.org
+Cc: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>, Paolo Abeni <pabeni@redhat.com>, Mat Martineau <martineau@kernel.org>, Jakub Kicinski <kuba@kernel.org>
+Message-ID: <20240812150213.489098-8-matttbe@kernel.org>
+
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+
+commit c95eb32ced823a00be62202b43966b07b2f20b7f upstream.
+
+That will simplify the following commits.
+
+No functional changes intended.
+
+Suggested-by: Paolo Abeni <pabeni@redhat.com>
+Reviewed-by: Mat Martineau <martineau@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-3-c8a9b036493b@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Stable-dep-of: cd7c957f936f ("mptcp: pm: don't try to create sf if alloc failed")
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/mptcp/pm_netlink.c | 19 +++++++++++--------
+ 1 file changed, 11 insertions(+), 8 deletions(-)
+
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -567,16 +567,19 @@ static void mptcp_pm_create_subflow_or_s
+ if (msk->pm.addr_signal & BIT(MPTCP_ADD_ADDR_SIGNAL))
+ return;
+
+- if (local) {
+- if (mptcp_pm_alloc_anno_list(msk, &local->addr)) {
+- __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
+- msk->pm.add_addr_signaled++;
+- mptcp_pm_announce_addr(msk, &local->addr, false);
+- mptcp_pm_nl_addr_send_ack(msk);
+- }
+- }
++ if (!local)
++ goto subflow;
++
++ if (!mptcp_pm_alloc_anno_list(msk, &local->addr))
++ goto subflow;
++
++ __clear_bit(local->addr.id, msk->pm.id_avail_bitmap);
++ msk->pm.add_addr_signaled++;
++ mptcp_pm_announce_addr(msk, &local->addr, false);
++ mptcp_pm_nl_addr_send_ack(msk);
+ }
+
++subflow:
+ /* check if should create a new subflow */
+ while (msk->pm.local_addr_used < local_addr_max &&
+ msk->pm.subflows < subflows_max) {
--- /dev/null
+From stable+bounces-66733-greg=kroah.com@vger.kernel.org Mon Aug 12 17:03:09 2024
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+Date: Mon, 12 Aug 2024 17:02:18 +0200
+Subject: selftests: mptcp: join: ability to invert ADD_ADDR check
+To: mptcp@lists.linux.dev, stable@vger.kernel.org, gregkh@linuxfoundation.org
+Cc: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>, Mat Martineau <martineau@kernel.org>, Jakub Kicinski <kuba@kernel.org>
+Message-ID: <20240812150213.489098-11-matttbe@kernel.org>
+
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+
+commit bec1f3b119ebc613d08dfbcdbaef01a79aa7de92 upstream.
+
+In the following commit, the client will initiate the ADD_ADDR, instead
+of the server. We need to way to verify the ADD_ADDR have been correctly
+sent.
+
+Note: the default expected counters for when the port number is given
+are never changed by the caller, no need to accept them as parameter
+then.
+
+The 'Fixes' tag here below is the same as the one from the previous
+commit: this patch here is not fixing anything wrong in the selftests,
+but it validates the previous fix for an issue introduced by this commit
+ID.
+
+Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk")
+Reviewed-by: Mat Martineau <martineau@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-6-c8a9b036493b@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ tools/testing/selftests/net/mptcp/mptcp_join.sh | 40 +++++++++++++++---------
+ 1 file changed, 26 insertions(+), 14 deletions(-)
+
+--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
++++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
+@@ -1415,18 +1415,28 @@ chk_add_nr()
+ local add_nr=$1
+ local echo_nr=$2
+ local port_nr=${3:-0}
+- local syn_nr=${4:-$port_nr}
+- local syn_ack_nr=${5:-$port_nr}
+- local ack_nr=${6:-$port_nr}
+- local mis_syn_nr=${7:-0}
+- local mis_ack_nr=${8:-0}
++ local ns_invert=${4:-""}
++ local syn_nr=$port_nr
++ local syn_ack_nr=$port_nr
++ local ack_nr=$port_nr
++ local mis_syn_nr=0
++ local mis_ack_nr=0
++ local ns_tx=$ns1
++ local ns_rx=$ns2
++ local extra_msg=""
+ local count
+ local timeout
+
+- timeout=$(ip netns exec $ns1 sysctl -n net.mptcp.add_addr_timeout)
++ if [[ $ns_invert = "invert" ]]; then
++ ns_tx=$ns2
++ ns_rx=$ns1
++ extra_msg="invert"
++ fi
++
++ timeout=$(ip netns exec ${ns_tx} sysctl -n net.mptcp.add_addr_timeout)
+
+ print_check "add"
+- count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtAddAddr")
++ count=$(mptcp_lib_get_counter ${ns_rx} "MPTcpExtAddAddr")
+ if [ -z "$count" ]; then
+ print_skip
+ # if the test configured a short timeout tolerate greater then expected
+@@ -1438,7 +1448,7 @@ chk_add_nr()
+ fi
+
+ print_check "echo"
+- count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtEchoAdd")
++ count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtEchoAdd")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$echo_nr" ]; then
+@@ -1449,7 +1459,7 @@ chk_add_nr()
+
+ if [ $port_nr -gt 0 ]; then
+ print_check "pt"
+- count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtPortAdd")
++ count=$(mptcp_lib_get_counter ${ns_rx} "MPTcpExtPortAdd")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$port_nr" ]; then
+@@ -1459,7 +1469,7 @@ chk_add_nr()
+ fi
+
+ print_check "syn"
+- count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPJoinPortSynRx")
++ count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMPJoinPortSynRx")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$syn_nr" ]; then
+@@ -1470,7 +1480,7 @@ chk_add_nr()
+ fi
+
+ print_check "synack"
+- count=$(mptcp_lib_get_counter ${ns2} "MPTcpExtMPJoinPortSynAckRx")
++ count=$(mptcp_lib_get_counter ${ns_rx} "MPTcpExtMPJoinPortSynAckRx")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$syn_ack_nr" ]; then
+@@ -1481,7 +1491,7 @@ chk_add_nr()
+ fi
+
+ print_check "ack"
+- count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMPJoinPortAckRx")
++ count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMPJoinPortAckRx")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$ack_nr" ]; then
+@@ -1492,7 +1502,7 @@ chk_add_nr()
+ fi
+
+ print_check "syn"
+- count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMismatchPortSynRx")
++ count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMismatchPortSynRx")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$mis_syn_nr" ]; then
+@@ -1503,7 +1513,7 @@ chk_add_nr()
+ fi
+
+ print_check "ack"
+- count=$(mptcp_lib_get_counter ${ns1} "MPTcpExtMismatchPortAckRx")
++ count=$(mptcp_lib_get_counter ${ns_tx} "MPTcpExtMismatchPortAckRx")
+ if [ -z "$count" ]; then
+ print_skip
+ elif [ "$count" != "$mis_ack_nr" ]; then
+@@ -1513,6 +1523,8 @@ chk_add_nr()
+ print_ok
+ fi
+ fi
++
++ print_info "$extra_msg"
+ }
+
+ chk_add_tx_nr()
--- /dev/null
+From stable+bounces-66734-greg=kroah.com@vger.kernel.org Mon Aug 12 17:03:21 2024
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+Date: Mon, 12 Aug 2024 17:02:19 +0200
+Subject: selftests: mptcp: join: test both signal & subflow
+To: mptcp@lists.linux.dev, stable@vger.kernel.org, gregkh@linuxfoundation.org
+Cc: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>, Mat Martineau <martineau@kernel.org>, Jakub Kicinski <kuba@kernel.org>
+Message-ID: <20240812150213.489098-12-matttbe@kernel.org>
+
+From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
+
+commit 4d2868b5d191c74262f7407972d68d1bf3245d6a upstream.
+
+It should be quite uncommon to set both the subflow and the signal
+flags: the initiator of the connection is typically the one creating new
+subflows, not the other peer, then no need to announce additional local
+addresses, and use it to create subflows.
+
+But some people might be confused about the flags, and set both "just to
+be sure at least the right one is set". To verify the previous fix, and
+avoid future regressions, this specific case is now validated: the
+client announces a new address, and initiates a new subflow from the
+same address.
+
+While working on this, another bug has been noticed, where the client
+reset the new subflow because an ADD_ADDR echo got received as the 3rd
+ACK: this new test also explicitly checks that no RST have been sent by
+the client and server.
+
+The 'Fixes' tag here below is the same as the one from the previous
+commit: this patch here is not fixing anything wrong in the selftests,
+but it validates the previous fix for an issue introduced by this commit
+ID.
+
+Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk")
+Reviewed-by: Mat Martineau <martineau@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Link: https://patch.msgid.link/20240731-upstream-net-20240731-mptcp-endp-subflow-signal-v1-7-c8a9b036493b@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ tools/testing/selftests/net/mptcp/mptcp_join.sh | 15 +++++++++++++++
+ 1 file changed, 15 insertions(+)
+
+--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
++++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
+@@ -1989,6 +1989,21 @@ signal_address_tests()
+ chk_add_nr 1 1
+ fi
+
++ # uncommon: subflow and signal flags on the same endpoint
++ # or because the user wrongly picked both, but still expects the client
++ # to create additional subflows
++ if reset "subflow and signal together"; then
++ pm_nl_set_limits $ns1 0 2
++ pm_nl_set_limits $ns2 0 2
++ pm_nl_add_endpoint $ns2 10.0.3.2 flags signal,subflow
++ run_tests $ns1 $ns2 10.0.1.1
++ chk_join_nr 1 1 1
++ chk_add_nr 1 1 0 invert # only initiated by ns2
++ chk_add_nr 0 0 0 # none initiated by ns1
++ chk_rst_nr 0 0 invert # no RST sent by the client
++ chk_rst_nr 0 0 # no RST sent by the server
++ fi
++
+ # accept and use add_addr with additional subflows
+ if reset "multiple subflows and signal"; then
+ pm_nl_set_limits $ns1 0 3
drm-amd-display-add-null-check-in-resource_log_pipe_topology_update.patch
drm-amd-display-change-assr-disable-sequence.patch
drm-amd-display-defer-handling-mst-up-request-in-resume.patch
+mptcp-pm-reduce-indentation-blocks.patch
+mptcp-pm-don-t-try-to-create-sf-if-alloc-failed.patch
+mptcp-pm-do-not-ignore-subflow-if-signal-flag-is-also-set.patch
+selftests-mptcp-join-ability-to-invert-add_addr-check.patch
+selftests-mptcp-join-test-both-signal-subflow.patch