FAILED: patch "[PATCH] selftests: mptcp: join: skip test if iptables/tc cmds fail" failed to apply to 5.15-stable tree

FAILED: patch "[PATCH] selftests: mptcp: join: skip test if iptables/tc cmds fail" failed to apply to 5.15-stable tree

[gregkh]

The patch below does not apply to the 5.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 4a0b866a3f7d3c22033f40e93e94befc6fe51bce
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023062219-thank-remedial-82cc@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 4a0b866a3f7d3c22033f40e93e94befc6fe51bce Mon Sep 17 00:00:00 2001
From: Matthieu Baerts <matthieu.baerts@tessares.net>
Date: Sat, 10 Jun 2023 18:11:40 +0200
Subject: [PATCH] selftests: mptcp: join: skip test if iptables/tc cmds fail

Selftests are supposed to run on any kernels, including the old ones not
supporting all MPTCP features.

Some tests are using IPTables and/or TC commands to force some
behaviours. If one of these commands fails -- likely because some
features are not available due to missing kernel config -- we should
intercept the error and skip the tests requiring these features.

Note that if we expect to have these features available and if
SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var is set to 1, the tests
will be marked as failed instead of skipped.

This patch also replaces the 'exit 1' by 'return 1' not to stop the
selftest in the middle without the conclusion if there is an issue with
NF or TC.

Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368
Fixes: 8d014eaa9254 ("selftests: mptcp: add ADD_ADDR timeout test case")
Cc: stable@vger.kernel.org
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 276396cbe60c..c471934ad5e0 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -286,11 +286,15 @@ reset_with_add_addr_timeout()
 	fi
 
 	ip netns exec $ns1 sysctl -q net.mptcp.add_addr_timeout=1
-	ip netns exec $ns2 $tables -A OUTPUT -p tcp \
-		-m tcp --tcp-option 30 \
-		-m bpf --bytecode \
-		"$CBPF_MPTCP_SUBOPTION_ADD_ADDR" \
-		-j DROP
+
+	if ! ip netns exec $ns2 $tables -A OUTPUT -p tcp \
+			-m tcp --tcp-option 30 \
+			-m bpf --bytecode \
+			"$CBPF_MPTCP_SUBOPTION_ADD_ADDR" \
+			-j DROP; then
+		mark_as_skipped "unable to set the 'add addr' rule"
+		return 1
+	fi
 }
 
 # $1: test name
@@ -334,17 +338,12 @@ reset_with_allow_join_id0()
 #     tc action pedit offset 162 out of bounds
 #
 # Netfilter is used to mark packets with enough data.
-reset_with_fail()
+setup_fail_rules()
 {
-	reset "${1}" || return 1
-
-	ip netns exec $ns1 sysctl -q net.mptcp.checksum_enabled=1
-	ip netns exec $ns2 sysctl -q net.mptcp.checksum_enabled=1
-
 	check_invert=1
 	validate_checksum=1
-	local i="$2"
-	local ip="${3:-4}"
+	local i="$1"
+	local ip="${2:-4}"
 	local tables
 
 	tables="${iptables}"
@@ -359,15 +358,32 @@ reset_with_fail()
 		-p tcp \
 		-m length --length 150:9999 \
 		-m statistic --mode nth --packet 1 --every 99999 \
-		-j MARK --set-mark 42 || exit 1
+		-j MARK --set-mark 42 || return ${ksft_skip}
 
-	tc -n $ns2 qdisc add dev ns2eth$i clsact || exit 1
+	tc -n $ns2 qdisc add dev ns2eth$i clsact || return ${ksft_skip}
 	tc -n $ns2 filter add dev ns2eth$i egress \
 		protocol ip prio 1000 \
 		handle 42 fw \
 		action pedit munge offset 148 u8 invert \
 		pipe csum tcp \
-		index 100 || exit 1
+		index 100 || return ${ksft_skip}
+}
+
+reset_with_fail()
+{
+	reset "${1}" || return 1
+	shift
+
+	ip netns exec $ns1 sysctl -q net.mptcp.checksum_enabled=1
+	ip netns exec $ns2 sysctl -q net.mptcp.checksum_enabled=1
+
+	local rc=0
+	setup_fail_rules "${@}" || rc=$?
+
+	if [ ${rc} -eq ${ksft_skip} ]; then
+		mark_as_skipped "unable to set the 'fail' rules"
+		return 1
+	fi
 }
 
 reset_with_events()
@@ -382,6 +398,25 @@ reset_with_events()
 	evts_ns2_pid=$!
 }
 
+reset_with_tcp_filter()
+{
+	reset "${1}" || return 1
+	shift
+
+	local ns="${!1}"
+	local src="${2}"
+	local target="${3}"
+
+	if ! ip netns exec "${ns}" ${iptables} \
+			-A INPUT \
+			-s "${src}" \
+			-p tcp \
+			-j "${target}"; then
+		mark_as_skipped "unable to set the filter rules"
+		return 1
+	fi
+}
+
 fail_test()
 {
 	ret=1
@@ -745,15 +780,6 @@ pm_nl_check_endpoint()
 	fi
 }
 
-filter_tcp_from()
-{
-	local ns="${1}"
-	local src="${2}"
-	local target="${3}"
-
-	ip netns exec "${ns}" ${iptables} -A INPUT -s "${src}" -p tcp -j "${target}"
-}
-
 do_transfer()
 {
 	local listener_ns="$1"
@@ -1975,23 +2001,23 @@ subflows_error_tests()
 	fi
 
 	# multiple subflows, with subflow creation error
-	if reset "multi subflows, with failing subflow"; then
+	if reset_with_tcp_filter "multi subflows, with failing subflow" ns1 10.0.3.2 REJECT &&
+	   continue_if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; 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 subflow
 		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
-		filter_tcp_from $ns1 10.0.3.2 REJECT
 		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
 		chk_join_nr 1 1 1
 	fi
 
 	# multiple subflows, with subflow timeout on MPJ
-	if reset "multi subflows, with subflow timeout"; then
+	if reset_with_tcp_filter "multi subflows, with subflow timeout" ns1 10.0.3.2 DROP &&
+	   continue_if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; 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 subflow
 		pm_nl_add_endpoint $ns2 10.0.2.2 flags subflow
-		filter_tcp_from $ns1 10.0.3.2 DROP
 		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow
 		chk_join_nr 1 1 1
 	fi
@@ -1999,11 +2025,11 @@ subflows_error_tests()
 	# multiple subflows, check that the endpoint corresponding to
 	# closed subflow (due to reset) is not reused if additional
 	# subflows are added later
-	if reset "multi subflows, fair usage on close"; then
+	if reset_with_tcp_filter "multi subflows, fair usage on close" ns1 10.0.3.2 REJECT &&
+	   continue_if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
 		pm_nl_set_limits $ns1 0 1
 		pm_nl_set_limits $ns2 0 1
 		pm_nl_add_endpoint $ns2 10.0.3.2 flags subflow
-		filter_tcp_from $ns1 10.0.3.2 REJECT
 		run_tests $ns1 $ns2 10.0.1.1 0 0 0 slow &
 
 		# mpj subflow will be in TW after the reset

Re: FAILED: patch "[PATCH] selftests: mptcp: join: skip test if iptables/tc cmds fail" failed to apply to 5.15-stable tree

[Matthieu Baerts]

Hi Greg,

On 22/06/2023 10:00, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 5.15-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.

(...)

> ------------------ original commit in Linus's tree ------------------
> 
> From 4a0b866a3f7d3c22033f40e93e94befc6fe51bce Mon Sep 17 00:00:00 2001
> From: Matthieu Baerts <matthieu.baerts@tessares.net>
> Date: Sat, 10 Jun 2023 18:11:40 +0200
> Subject: [PATCH] selftests: mptcp: join: skip test if iptables/tc cmds fail
> 
> Selftests are supposed to run on any kernels, including the old ones not
> supporting all MPTCP features.
> 
> Some tests are using IPTables and/or TC commands to force some
> behaviours. If one of these commands fails -- likely because some
> features are not available due to missing kernel config -- we should
> intercept the error and skip the tests requiring these features.
> 
> Note that if we expect to have these features available and if
> SELFTESTS_MPTCP_LIB_EXPECT_ALL_FEATURES env var is set to 1, the tests
> will be marked as failed instead of skipped.
> 
> This patch also replaces the 'exit 1' by 'return 1' not to stop the
> selftest in the middle without the conclusion if there is an issue with
> NF or TC.
> 
> Link: https://github.com/multipath-tcp/mptcp_net-next/issues/368
> Fixes: 8d014eaa9254 ("selftests: mptcp: add ADD_ADDR timeout test case")
> Cc: stable@vger.kernel.org
> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Thank you for this notification!

We don't need to backport this commit 4a0b866a3f7d ("selftests: mptcp:
join: skip test if iptables/tc cmds fail"): it depends on a feature
introduced in commit ae7bd9ccecc3 ("selftests: mptcp: join: option to
execute specific tests") and we don't want to backport this. Also, this
fix here is mainly useful for the last stable version: I guess people
will likely not take the selftests version from v5.15.y and run them on
older kernels. They will more likely take the selftests from the last
stable version (or the same version as the kernel one).

So no need to do anything here.

Cheers,
Matt
-- 
Tessares | Belgium | Hybrid Access Solutions
www.tessares.net