[PATCH 5.10 146/147] selftests: forwarding: tc_actions: Use ncat instead of nc

Sasha Levin
2026-02-28T18:19:33Z

From: Ido Schimmel <idosch@nvidia.com>

[ Upstream commit 5e8670610b93158ffacc3241f835454ff26a3469 ]

The test relies on 'nc' being the netcat version from the nmap project.
While this seems to be the case on Fedora, it is not the case on Ubuntu,
resulting in failures such as [1].

Fix by explicitly using the 'ncat' utility from the nmap project and the
skip the test in case it is not installed.

[1]
# timeout set to 0
# selftests: net/forwarding: tc_actions.sh
# TEST: gact drop and ok (skip_hw) [ OK ]
# TEST: mirred egress flower redirect (skip_hw) [ OK ]
# TEST: mirred egress flower mirror (skip_hw) [ OK ]
# TEST: mirred egress matchall mirror (skip_hw) [ OK ]
# TEST: mirred_egress_to_ingress (skip_hw) [ OK ]
# nc: invalid option -- '-'
# usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-M ttl]
# [-m minttl] [-O length] [-P proxy_username] [-p source_port]
# [-q seconds] [-s sourceaddr] [-T keyword] [-V rtable] [-W recvlimit]
# [-w timeout] [-X proxy_protocol] [-x proxy_address[:port]]
# [destination] [port]
# nc: invalid option -- '-'
# usage: nc [-46CDdFhklNnrStUuvZz] [-I length] [-i interval] [-M ttl]
# [-m minttl] [-O length] [-P proxy_username] [-p source_port]
# [-q seconds] [-s sourceaddr] [-T keyword] [-V rtable] [-W recvlimit]
# [-w timeout] [-X proxy_protocol] [-x proxy_address[:port]]
# [destination] [port]
# TEST: mirred_egress_to_ingress_tcp (skip_hw) [FAIL]
# server output check failed
# INFO: Could not test offloaded functionality
not ok 80 selftests: net/forwarding: tc_actions.sh # exit=1

Fixes: ca22da2fbd69 ("act_mirred: use the backlog for nested calls to mirred ingress")
Reported-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Closes: https://lore.kernel.org/netdev/adc5e40d-d040-a65e-eb26-edf47dac5b02@alu.unizg.hr/
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20230808141503.4060661-12-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 32b70e62034a ("selftests: tc_actions: don't dump 2MB of \0 to stdout")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
tools/testing/selftests/net/forwarding/tc_actions.sh | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/net/forwarding/tc_actions.sh b/tools/testing/selftests/net/forwarding/tc_actions.sh
index 9c2aca8a4b8de..dd02ed4cacacb 100755
--- a/tools/testing/selftests/net/forwarding/tc_actions.sh
+++ b/tools/testing/selftests/net/forwarding/tc_actions.sh
@@ -8,6 +8,8 @@ NUM_NETIFS=4
source tc_common.sh
source lib.sh

+require_command ncat
+
tcflags="skip_hw"

h1_create()
@@ -174,9 +176,9 @@ mirred_egress_to_ingress_tcp_test()
ip_proto icmp \
action drop

- ip vrf exec v$h1 nc --recv-only -w10 -l -p 12345 -o $mirred_e2i_tf2 &
+ ip vrf exec v$h1 ncat --recv-only -w10 -l -p 12345 -o $mirred_e2i_tf2 &
local rpid=$!
- ip vrf exec v$h1 nc -w1 --send-only 192.0.2.2 12345 <$mirred_e2i_tf1
+ ip vrf exec v$h1 ncat -w1 --send-only 192.0.2.2 12345 <$mirred_e2i_tf1
wait -n $rpid
cmp -s $mirred_e2i_tf1 $mirred_e2i_tf2
check_err $? "server output check failed"
--
2.51.0