selftests: mptcp: join: cannot rm sf if closed

commit e93681afcb96864ec26c3b2ce94008ce93577373 upstream.

Thanks to the previous commit, the MPTCP subflows are now closed on both directions even when only the MPTCP path-manager of one peer asks for their closure.

In the two tests modified here -- "userspace pm add & remove address" and "userspace pm create destroy subflow" -- one peer is controlled by the userspace PM, and the other one by the in-kernel PM. When the userspace PM sends a RM_ADDR notification, the in-kernel PM will automatically react by closing all subflows using this address. Now, thanks to the previous commit, the subflows are properly closed on both directions, the userspace PM can then no longer closes the same subflows if they are already closed. Before, it was OK to do that, because the subflows were still half-opened, still OK to send a RM_ADDR.

In other words, thanks to the previous commit closing the subflows, an error will be returned to the userspace if it tries to close a subflow that has already been closed. So no need to run this command, which mean that the linked counters will then not be incremented.

These tests are then no longer sending both a RM_ADDR, then closing the linked subflow just after. The test with the userspace PM on the server side is now removing one subflow linked to one address, then sending a RM_ADDR for another address. The test with the userspace PM on the client side is now only removing the subflow that was previously created.

[ It looks like this patch is needed for the same reasons as mentioned
above, but the resolution is different: the subflows and addresses are removed elsewhere. The same type of adaptations have been applied here. The Fixes tag has been replaced by better appropriated ones. ]

---
 tools/testing/selftests/net/mptcp/mptcp_join.sh | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

index 20561d569697..446b8daa23e0 100755
@@ -984,8 +984,6 @@ do_transfer()
 				dp=$(grep "type:10" "$evts_ns1" |
 				     sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q')
 				ip netns exec ${listener_ns} ./pm_nl_ctl rem token $tk id $id
-				ip netns exec ${listener_ns} ./pm_nl_ctl dsf lip "$addr" \
-							lport $sp rip $da rport $dp token $tk
 			fi
 
 			counter=$((counter + 1))

@@ -1051,7 +1049,6 @@ do_transfer()
 				sleep 1
 				sp=$(grep "type:10" "$evts_ns2" |
 				     sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
-				ip netns exec ${connector_ns} ./pm_nl_ctl rem token $tk id $id
 				ip netns exec ${connector_ns} ./pm_nl_ctl dsf lip $addr lport $sp \
 									rip $da rport $dp token $tk
 			fi

@@ -3280,7 +3277,7 @@ userspace_tests()
 		run_tests $ns1 $ns2 10.0.1.1 0 userspace_1 0 slow
 		chk_join_nr 1 1 1
 		chk_add_nr 1 1
-		chk_rm_nr 1 1 invert
+		chk_rm_nr 1 0 invert
 	fi
 
 	# userspace pm create destroy subflow

@@ -3290,7 +3287,7 @@ userspace_tests()
 		pm_nl_set_limits $ns1 0 1
 		run_tests $ns1 $ns2 10.0.1.1 0 0 userspace_1 slow
 		chk_join_nr 1 1 1
-		chk_rm_nr 1 1
+		chk_rm_nr 0 1
 	fi
 }
 

2.45.2

Applied

This is a note to let you know that I've just added the patch titled

selftests: mptcp: join: cannot rm sf if closed

to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
selftests-mptcp-join-cannot-rm-sf-if-closed.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From [email protected] Wed Sep 4 13:19:25 2024
From: "Matthieu Baerts (NGI0)" <[email protected]>
Date: Wed, 4 Sep 2024 13:15:48 +0200
Subject: selftests: mptcp: join: cannot rm sf if closed
To: [email protected], [email protected]
Cc: MPTCP Upstream <[email protected]>, "Matthieu Baerts (NGI0)" <[email protected]>, Mat Martineau <[email protected]>, Jakub Kicinski <[email protected]>
Message-ID: <[email protected]>

From: "Matthieu Baerts (NGI0)" <[email protected]>

commit e93681afcb96864ec26c3b2ce94008ce93577373 upstream.

Thanks to the previous commit, the MPTCP subflows are now closed on both directions even when only the MPTCP path-manager of one peer asks for their closure.

In the two tests modified here -- "userspace pm add & remove address" and "userspace pm create destroy subflow" -- one peer is controlled by the userspace PM, and the other one by the in-kernel PM. When the userspace PM sends a RM_ADDR notification, the in-kernel PM will automatically react by closing all subflows using this address. Now, thanks to the previous commit, the subflows are properly closed on both directions, the userspace PM can then no longer closes the same subflows if they are already closed. Before, it was OK to do that, because the subflows were still half-opened, still OK to send a RM_ADDR.

In other words, thanks to the previous commit closing the subflows, an error will be returned to the userspace if it tries to close a subflow that has already been closed. So no need to run this command, which mean that the linked counters will then not be incremented.

These tests are then no longer sending both a RM_ADDR, then closing the linked subflow just after. The test with the userspace PM on the server side is now removing one subflow linked to one address, then sending a RM_ADDR for another address. The test with the userspace PM on the client side is now only removing the subflow that was previously created.

[ It looks like this patch is needed for the same reasons as mentioned
above, but the resolution is different: the subflows and addresses are removed elsewhere. The same type of adaptations have been applied here. The Fixes tag has been replaced by better appropriated ones. ]

---
 tools/testing/selftests/net/mptcp/mptcp_join.sh |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

@@ -957,8 +957,6 @@ do_transfer()
 				dp=$(grep "type:10" "$evts_ns1" |
 				     sed -n 's/.*\(dport:\)\([[:digit:]]*\).*$/\2/p;q')
 				ip netns exec ${listener_ns} ./pm_nl_ctl rem token $tk id $id
-				ip netns exec ${listener_ns} ./pm_nl_ctl dsf lip "$addr" \
-							lport $sp rip $da rport $dp token $tk
 			fi
 
 			counter=$((counter + 1))

@@ -1024,7 +1022,6 @@ do_transfer()
 				sleep 1
 				sp=$(grep "type:10" "$evts_ns2" |
 				     sed -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q')
-				ip netns exec ${connector_ns} ./pm_nl_ctl rem token $tk id $id
 				ip netns exec ${connector_ns} ./pm_nl_ctl dsf lip $addr lport $sp \
 									rip $da rport $dp token $tk
 			fi

@@ -3227,7 +3224,7 @@ userspace_tests()
 		run_tests $ns1 $ns2 10.0.1.1 0 userspace_1 0 slow
 		chk_join_nr 1 1 1
 		chk_add_nr 1 1
-		chk_rm_nr 1 1 invert
+		chk_rm_nr 1 0 invert
 	fi
 
 	# userspace pm create destroy subflow

@@ -3237,7 +3234,7 @@ userspace_tests()
 		pm_nl_set_limits $ns1 0 1
 		run_tests $ns1 $ns2 10.0.1.1 0 0 userspace_1 slow
 		chk_join_nr 1 1 1
-		chk_rm_nr 1 1
+		chk_rm_nr 0 1
 	fi
 
 	# remove and re-add

Patches currently in stable-queue which might be from [email protected] are

queue-6.1/selftests-mptcp-join-cannot-rm-sf-if-closed.patch queue-6.1/mptcp-pm-fix-rm_addr-id-for-the-initial-subflow.patch queue-6.1/selftests-mptcp-join-validate-fullmesh-endp-on-1st-sf.patch queue-6.1/mptcp-pm-fix-id-0-endp-usage-after-multiple-re-creations.patch queue-6.1/mptcp-make-pm_remove_addrs_and_subflows-static.patch queue-6.1/mptcp-pm-avoid-possible-uaf-when-selecting-endp.patch queue-6.1/mptcp-pm-reuse-id-0-after-delete-and-re-add.patch queue-6.1/selftests-mptcp-join-check-re-adding-init-endp-with-id.patch queue-6.1/selftests-mptcp-join-test-for-flush-re-add-endpoints.patch queue-6.1/selftests-mptcp-add-explicit-test-case-for-remove-re.patch queue-6.1/mptcp-avoid-duplicated-sub_closed-events.patch queue-6.1/selftests-mptcp-add-explicit-test-case-for-remove-readd.patch queue-6.1/selftests-mptcp-join-check-re-adding-init-endp-with-.patch queue-6.1/selftests-mptcp-join-check-re-using-id-of-closed-subflow.patch queue-6.1/selftests-mptcp-join-check-re-re-adding-id-0-endp.patch queue-6.1/mptcp-pm-fullmesh-select-the-right-id-later.patch queue-6.1/selftests-mptcp-join-no-extra-msg-if-no-counter.patch queue-6.1/mptcp-pr_debug-add-missing-n-at-the-end.patch queue-6.1/selftests-mptcp-join-check-re-using-id-of-unused-add.patch queue-6.1/selftests-mptcp-join-check-removing-id-0-endpoint.patch queue-6.1/selftests-mptcp-join-check-re-using-id-of-unused-add_addr.patch