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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Jiri Benc <jbenc@redhat.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.14 117/172] selftests, bpf: test_lwt_ip_encap: Really disable rp_filter
Date:   Mon,  4 Oct 2021 14:52:47 +0200
Message-Id: <20211004125048.759890007@linuxfoundation.org>
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From: Jiri Benc <jbenc@redhat.com>

[ Upstream commit 79e2c306667542b8ee2d9a9d947eadc7039f0a3c ]

It's not enough to set net.ipv4.conf.all.rp_filter=0, that does not override
a greater rp_filter value on the individual interfaces. We also need to set
net.ipv4.conf.default.rp_filter=0 before creating the interfaces. That way,
they'll also get their own rp_filter value of zero.

Fixes: 0fde56e4385b0 ("selftests: bpf: add test_lwt_ip_encap selftest")
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/b1cdd9d469f09ea6e01e9c89a6071c79b7380f89.1632386362.git.jbenc@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/testing/selftests/bpf/test_lwt_ip_encap.sh | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_lwt_ip_encap.sh b/tools/testing/selftests/bpf/test_lwt_ip_encap.sh
index 59ea56945e6c..b497bb85b667 100755
--- a/tools/testing/selftests/bpf/test_lwt_ip_encap.sh
+++ b/tools/testing/selftests/bpf/test_lwt_ip_encap.sh
@@ -112,6 +112,14 @@ setup()
 	ip netns add "${NS2}"
 	ip netns add "${NS3}"
 
+	# rp_filter gets confused by what these tests are doing, so disable it
+	ip netns exec ${NS1} sysctl -wq net.ipv4.conf.all.rp_filter=0
+	ip netns exec ${NS2} sysctl -wq net.ipv4.conf.all.rp_filter=0
+	ip netns exec ${NS3} sysctl -wq net.ipv4.conf.all.rp_filter=0
+	ip netns exec ${NS1} sysctl -wq net.ipv4.conf.default.rp_filter=0
+	ip netns exec ${NS2} sysctl -wq net.ipv4.conf.default.rp_filter=0
+	ip netns exec ${NS3} sysctl -wq net.ipv4.conf.default.rp_filter=0
+
 	ip link add veth1 type veth peer name veth2
 	ip link add veth3 type veth peer name veth4
 	ip link add veth5 type veth peer name veth6
@@ -236,11 +244,6 @@ setup()
 	ip -netns ${NS1} -6 route add ${IPv6_GRE}/128 dev veth5 via ${IPv6_6} ${VRF}
 	ip -netns ${NS2} -6 route add ${IPv6_GRE}/128 dev veth7 via ${IPv6_8} ${VRF}
 
-	# rp_filter gets confused by what these tests are doing, so disable it
-	ip netns exec ${NS1} sysctl -wq net.ipv4.conf.all.rp_filter=0
-	ip netns exec ${NS2} sysctl -wq net.ipv4.conf.all.rp_filter=0
-	ip netns exec ${NS3} sysctl -wq net.ipv4.conf.all.rp_filter=0
-
 	TMPFILE=$(mktemp /tmp/test_lwt_ip_encap.XXXXXX)
 
 	sleep 1  # reduce flakiness
-- 
2.33.0