[PATCH 5.14 117/172] selftests, bpf: test_lwt_ip_encap: Really disable rp_filter

From: Greg Kroah-Hartman
Date: Mon Oct 04 2021 - 09:37:19 EST


From: Jiri Benc <jbenc@xxxxxxxxxx>

[ 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@xxxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/bpf/b1cdd9d469f09ea6e01e9c89a6071c79b7380f89.1632386362.git.jbenc@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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