1 files changed, 246 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/lwt_dst_cache_ref_loop.sh b/tools/testing/selftests/net/lwt_dst_cache_ref_loop.sh
new file mode 100755
index 000000000000..881eb399798f
--- /dev/null
+++ b/tools/testing/selftests/net/lwt_dst_cache_ref_loop.sh
@@ -0,0 +1,246 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Author: Justin Iurman <justin.iurman@uliege.be>
+#
+# WARNING
+# -------
+# This is just a dummy script that triggers encap cases with possible dst cache
+# reference loops in affected lwt users (see list below). Some cases are
+# pathological configurations for simplicity, others are valid. Overall, we
+# don't want this issue to happen, no matter what. In order to catch any
+# reference loops, kmemleak MUST be used. The results alone are always blindly
+# successful, don't rely on them. Note that the following tests may crash the
+# kernel if the fix to prevent lwtunnel_{input|output|xmit}() reentry loops is
+# not present.
+#
+# Affected lwt users so far (please update accordingly if needed):
+#  - ila_lwt (output only)
+#  - ioam6_iptunnel (output only)
+#  - rpl_iptunnel (both input and output)
+#  - seg6_iptunnel (both input and output)
+
+source lib.sh
+
+check_compatibility()
+{
+	setup_ns tmp_node &>/dev/null
+	if [ $? != 0 ]; then
+		echo "SKIP: Cannot create netns."
+		exit $ksft_skip
+	fi
+
+	ip link add name veth0 netns $tmp_node type veth \
+		peer name veth1 netns $tmp_node &>/dev/null
+	local ret=$?
+
+	ip -netns $tmp_node link set veth0 up &>/dev/null
+	ret=$((ret + $?))
+
+	ip -netns $tmp_node link set veth1 up &>/dev/null
+	ret=$((ret + $?))
+
+	if [ $ret != 0 ]; then
+		echo "SKIP: Cannot configure links."
+		cleanup_ns $tmp_node
+		exit $ksft_skip
+	fi
+
+	lsmod 2>/dev/null | grep -q "ila"
+	ila_lsmod=$?
+	[ $ila_lsmod != 0 ] && modprobe ila &>/dev/null
+
+	ip -netns $tmp_node route add 2001:db8:1::/64 \
+		encap ila 1:2:3:4 csum-mode no-action ident-type luid \
+			hook-type output \
+		dev veth0 &>/dev/null
+
+	ip -netns $tmp_node route add 2001:db8:2::/64 \
+		encap ioam6 trace prealloc type 0x800000 ns 0 size 4 \
+		dev veth0 &>/dev/null
+
+	ip -netns $tmp_node route add 2001:db8:3::/64 \
+		encap rpl segs 2001:db8:3::1 dev veth0 &>/dev/null
+
+	ip -netns $tmp_node route add 2001:db8:4::/64 \
+		encap seg6 mode inline segs 2001:db8:4::1 dev veth0 &>/dev/null
+
+	ip -netns $tmp_node -6 route 2>/dev/null | grep -q "encap ila"
+	skip_ila=$?
+
+	ip -netns $tmp_node -6 route 2>/dev/null | grep -q "encap ioam6"
+	skip_ioam6=$?
+
+	ip -netns $tmp_node -6 route 2>/dev/null | grep -q "encap rpl"
+	skip_rpl=$?
+
+	ip -netns $tmp_node -6 route 2>/dev/null | grep -q "encap seg6"
+	skip_seg6=$?
+
+	cleanup_ns $tmp_node
+}
+
+setup()
+{
+	setup_ns alpha beta gamma &>/dev/null
+
+	ip link add name veth-alpha netns $alpha type veth \
+		peer name veth-betaL netns $beta &>/dev/null
+
+	ip link add name veth-betaR netns $beta type veth \
+		peer name veth-gamma netns $gamma &>/dev/null
+
+	ip -netns $alpha link set veth-alpha name veth0 &>/dev/null
+	ip -netns $beta link set veth-betaL name veth0 &>/dev/null
+	ip -netns $beta link set veth-betaR name veth1 &>/dev/null
+	ip -netns $gamma link set veth-gamma name veth0 &>/dev/null
+
+	ip -netns $alpha addr add 2001:db8:1::2/64 dev veth0 &>/dev/null
+	ip -netns $alpha link set veth0 up &>/dev/null
+	ip -netns $alpha link set lo up &>/dev/null
+	ip -netns $alpha route add 2001:db8:2::/64 \
+		via 2001:db8:1::1 dev veth0 &>/dev/null
+
+	ip -netns $beta addr add 2001:db8:1::1/64 dev veth0 &>/dev/null
+	ip -netns $beta addr add 2001:db8:2::1/64 dev veth1 &>/dev/null
+	ip -netns $beta link set veth0 up &>/dev/null
+	ip -netns $beta link set veth1 up &>/dev/null
+	ip -netns $beta link set lo up &>/dev/null
+	ip -netns $beta route del 2001:db8:2::/64
+	ip -netns $beta route add 2001:db8:2::/64 dev veth1
+	ip netns exec $beta \
+		sysctl -wq net.ipv6.conf.all.forwarding=1 &>/dev/null
+
+	ip -netns $gamma addr add 2001:db8:2::2/64 dev veth0 &>/dev/null
+	ip -netns $gamma link set veth0 up &>/dev/null
+	ip -netns $gamma link set lo up &>/dev/null
+	ip -netns $gamma route add 2001:db8:1::/64 \
+		via 2001:db8:2::1 dev veth0 &>/dev/null
+
+	sleep 1
+
+	ip netns exec $alpha ping6 -c 5 -W 1 2001:db8:2::2 &>/dev/null
+	if [ $? != 0 ]; then
+		echo "SKIP: Setup failed."
+		exit $ksft_skip
+	fi
+
+	sleep 1
+}
+
+cleanup()
+{
+	cleanup_ns $alpha $beta $gamma
+	[ $ila_lsmod != 0 ] && modprobe -r ila &>/dev/null
+}
+
+run_ila()
+{
+	if [ $skip_ila != 0 ]; then
+		echo "SKIP: ila (output)"
+		return
+	fi
+
+	ip -netns $beta route del 2001:db8:2::/64
+	ip -netns $beta route add 2001:db8:2:0:0:0:0:2/128 \
+		encap ila 2001:db8:2:0 csum-mode no-action ident-type luid \
+			hook-type output \
+		dev veth1 &>/dev/null
+	sleep 1
+
+	echo "TEST: ila (output)"
+	ip netns exec $beta ping6 -c 2 -W 1 2001:db8:2::2 &>/dev/null
+	sleep 1
+
+	ip -netns $beta route del 2001:db8:2:0:0:0:0:2/128
+	ip -netns $beta route add 2001:db8:2::/64 dev veth1
+	sleep 1
+}
+
+run_ioam6()
+{
+	if [ $skip_ioam6 != 0 ]; then
+		echo "SKIP: ioam6 (output)"
+		return
+	fi
+
+	ip -netns $beta route change 2001:db8:2::/64 \
+		encap ioam6 trace prealloc type 0x800000 ns 1 size 4 \
+		dev veth1 &>/dev/null
+	sleep 1
+
+	echo "TEST: ioam6 (output)"
+	ip netns exec $beta ping6 -c 2 -W 1 2001:db8:2::2 &>/dev/null
+	sleep 1
+}
+
+run_rpl()
+{
+	if [ $skip_rpl != 0 ]; then
+		echo "SKIP: rpl (input)"
+		echo "SKIP: rpl (output)"
+		return
+	fi
+
+	ip -netns $beta route change 2001:db8:2::/64 \
+		encap rpl segs 2001:db8:2::2 \
+		dev veth1 &>/dev/null
+	sleep 1
+
+	echo "TEST: rpl (input)"
+	ip netns exec $alpha ping6 -c 2 -W 1 2001:db8:2::2 &>/dev/null
+	sleep 1
+
+	echo "TEST: rpl (output)"
+	ip netns exec $beta ping6 -c 2 -W 1 2001:db8:2::2 &>/dev/null
+	sleep 1
+}
+
+run_seg6()
+{
+	if [ $skip_seg6 != 0 ]; then
+		echo "SKIP: seg6 (input)"
+		echo "SKIP: seg6 (output)"
+		return
+	fi
+
+	ip -netns $beta route change 2001:db8:2::/64 \
+		encap seg6 mode inline segs 2001:db8:2::2 \
+		dev veth1 &>/dev/null
+	sleep 1
+
+	echo "TEST: seg6 (input)"
+	ip netns exec $alpha ping6 -c 2 -W 1 2001:db8:2::2 &>/dev/null
+	sleep 1
+
+	echo "TEST: seg6 (output)"
+	ip netns exec $beta ping6 -c 2 -W 1 2001:db8:2::2 &>/dev/null
+	sleep 1
+}
+
+run()
+{
+	run_ila
+	run_ioam6
+	run_rpl
+	run_seg6
+}
+
+if [ "$(id -u)" -ne 0 ]; then
+	echo "SKIP: Need root privileges."
+	exit $ksft_skip
+fi
+
+if [ ! -x "$(command -v ip)" ]; then
+	echo "SKIP: Could not run test without ip tool."
+	exit $ksft_skip
+fi
+
+check_compatibility
+
+trap cleanup EXIT
+
+setup
+run
+
+exit $ksft_pass