From: Hangbin Liu <liuhangbin@xxxxxxxxx> The test_local_dnat_portonly() function initiates the client-side as soon as it sets the listening side to the background. This could lead to a race condition where the server may not be ready to listen. To ensure that the server-side is up and running before initiating the client-side, a delay is introduced to the test_local_dnat_portonly() function. Before the fix: # ./nft_nat.sh PASS: netns routing/connectivity: ns0-rthlYrBU can reach ns1-rthlYrBU and ns2-rthlYrBU PASS: ping to ns1-rthlYrBU was ip NATted to ns2-rthlYrBU PASS: ping to ns1-rthlYrBU OK after ip nat output chain flush PASS: ipv6 ping to ns1-rthlYrBU was ip6 NATted to ns2-rthlYrBU 2023/02/27 04:11:03 socat[6055] E connect(5, AF=2 10.0.1.99:2000, 16): Connection refused ERROR: inet port rewrite After the fix: # ./nft_nat.sh PASS: netns routing/connectivity: ns0-9sPJV6JJ can reach ns1-9sPJV6JJ and ns2-9sPJV6JJ PASS: ping to ns1-9sPJV6JJ was ip NATted to ns2-9sPJV6JJ PASS: ping to ns1-9sPJV6JJ OK after ip nat output chain flush PASS: ipv6 ping to ns1-9sPJV6JJ was ip6 NATted to ns2-9sPJV6JJ PASS: inet port rewrite without l3 address Fixes: 282e5f8fe907 ("netfilter: nat: really support inet nat without l3 address") Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> --- tools/testing/selftests/netfilter/nft_nat.sh | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/netfilter/nft_nat.sh b/tools/testing/selftests/netfilter/nft_nat.sh index 924ecb3f1f73..dd40d9f6f259 100755 --- a/tools/testing/selftests/netfilter/nft_nat.sh +++ b/tools/testing/selftests/netfilter/nft_nat.sh @@ -404,6 +404,8 @@ EOF echo SERVER-$family | ip netns exec "$ns1" timeout 5 socat -u STDIN TCP-LISTEN:2000 & sc_s=$! + sleep 1 + result=$(ip netns exec "$ns0" timeout 1 socat TCP:$daddr:2000 STDOUT) if [ "$result" = "SERVER-inet" ];then -- 2.30.2