5.15-stable patches

added patches:
	mptcp-don-t-account-accept-of-non-mpc-client-as-fallback-to-tcp.patch

diff --git a/queue-5.15/mptcp-don-t-account-accept-of-non-mpc-client-as-fallback-to-tcp.patch b/queue-5.15/mptcp-don-t-account-accept-of-non-mpc-client-as-fallback-to-tcp.patch
new file mode 100644 (file)
index 0000000..4bcf681
--- /dev/null
+++ b/queue-5.15/mptcp-don-t-account-accept-of-non-mpc-client-as-fallback-to-tcp.patch
@@ -0,0 +1,93 @@
+From 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 Mon Sep 17 00:00:00 2001
+From: Davide Caratti <dcaratti@redhat.com>
+Date: Fri, 29 Mar 2024 13:08:52 +0100
+Subject: mptcp: don't account accept() of non-MPC client as fallback to TCP
+
+From: Davide Caratti <dcaratti@redhat.com>
+
+commit 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 upstream.
+
+Current MPTCP servers increment MPTcpExtMPCapableFallbackACK when they
+accept non-MPC connections. As reported by Christoph, this is "surprising"
+because the counter might become greater than MPTcpExtMPCapableSYNRX.
+
+MPTcpExtMPCapableFallbackACK counter's name suggests it should only be
+incremented when a connection was seen using MPTCP options, then a
+fallback to TCP has been done. Let's do that by incrementing it when
+the subflow context of an inbound MPC connection attempt is dropped.
+Also, update mptcp_connect.sh kselftest, to ensure that the
+above MIB does not increment in case a pure TCP client connects to a
+MPTCP server.
+
+Fixes: fc518953bc9c ("mptcp: add and use MIB counter infrastructure")
+Cc: stable@vger.kernel.org
+Reported-by: Christoph Paasch <cpaasch@apple.com>
+Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/449
+Signed-off-by: Davide Caratti <dcaratti@redhat.com>
+Reviewed-by: Mat Martineau <martineau@kernel.org>
+Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
+Link: https://lore.kernel.org/r/20240329-upstream-net-20240329-fallback-mib-v1-1-324a8981da48@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/protocol.c                               |    3 ---
+ net/mptcp/subflow.c                                |    3 +++
+ tools/testing/selftests/net/mptcp/mptcp_connect.sh |    7 +++++++
+ 3 files changed, 10 insertions(+), 3 deletions(-)
+
+--- a/net/mptcp/protocol.c
++++ b/net/mptcp/protocol.c
+@@ -3018,9 +3018,6 @@ static struct sock *mptcp_accept(struct
+               sock_hold(new_mptcp_sock);
+               newsk = new_mptcp_sock;
+               MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVEACK);
+-      } else {
+-              MPTCP_INC_STATS(sock_net(sk),
+-                              MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
+       }
+ 
+ out:
+--- a/net/mptcp/subflow.c
++++ b/net/mptcp/subflow.c
+@@ -725,6 +725,9 @@ create_child:
+                               goto dispose_child;
+                       }
+ 
++                      if (fallback)
++                              SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK);
++
+                       subflow_drop_ctx(child);
+                       goto out;
+               }
+--- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh
++++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
+@@ -451,6 +451,7 @@ do_transfer()
+       local stat_cookierx_last=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv")
+       local stat_csum_err_s=$(get_mib_counter "${listener_ns}" "MPTcpExtDataCsumErr")
+       local stat_csum_err_c=$(get_mib_counter "${connector_ns}" "MPTcpExtDataCsumErr")
++      local stat_tcpfb_last_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK")
+ 
+       timeout ${timeout_test} \
+               ip netns exec ${listener_ns} \
+@@ -516,6 +517,7 @@ do_transfer()
+       local stat_cookietx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesSent")
+       local stat_cookierx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv")
+       local stat_ooo_now=$(get_mib_counter "${listener_ns}" "TcpExtTCPOFOQueue")
++      local stat_tcpfb_now_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK")
+ 
+       expect_synrx=$((stat_synrx_last_l))
+       expect_ackrx=$((stat_ackrx_last_l))
+@@ -560,6 +562,11 @@ do_transfer()
+               fi
+       fi
+ 
++      if [ ${stat_ooo_now} -eq 0 ] && [ ${stat_tcpfb_last_l} -ne ${stat_tcpfb_now_l} ]; then
++              printf "[ FAIL ]\nunexpected fallback to TCP"
++              rets=1
++      fi
++
+       if [ $retc -eq 0 ] && [ $rets -eq 0 ]; then
+               printf "[ OK ]"
+       fi

diff --git a/queue-5.15/series b/queue-5.15/series
index 3c37b486333e227bf8b5d60272b07b15fd37c4bd..5e7032bc50e01f206f942c799ac27592d4fa6fa3 100644 (file)
--- a/queue-5.15/series
+++ b/queue-5.15/series
@@ -684,3 +684,4 @@ riscv-fix-spurious-errors-from-__get-put_kernel_nofault.patch
 riscv-process-fix-kernel-gp-leakage.patch
 x86-bugs-fix-the-srso-mitigation-on-zen3-4.patch
 x86-retpoline-do-the-necessary-fixup-to-the-zen3-4-srso-return-thunk-for-srso.patch
+mptcp-don-t-account-accept-of-non-mpc-client-as-fallback-to-tcp.patch