[PATCH 5.15 039/139] selftests: mptcp: fix diag instability

Greg Kroah-Hartman
2022-02-28T17:51:35Z

From: Paolo Abeni <pabeni@redhat.com>

commit 0cd33c5ffec12bd77a1c02db2469fac08f840939 upstream.

Instead of waiting for an arbitrary amount of time for the MPTCP
MP_CAPABLE handshake to complete, explicitly wait for the relevant
socket to enter into the established status.

Additionally let the data transfer application use the slowest
transfer mode available (-r), to cope with very slow host, or
high jitter caused by hosting VMs.

Fixes: df62f2ec3df6 ("selftests/mptcp: add diag interface tests")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/258
Reported-and-tested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
tools/testing/selftests/net/mptcp/diag.sh | 44 +++++++++++++++++++++++++-----
1 file changed, 37 insertions(+), 7 deletions(-)

--- a/tools/testing/selftests/net/mptcp/diag.sh
+++ b/tools/testing/selftests/net/mptcp/diag.sh
@@ -71,6 +71,36 @@ chk_msk_remote_key_nr()
__chk_nr "grep -c remote_key" $*
}

+# $1: ns, $2: port
+wait_local_port_listen()
+{
+ local listener_ns="${1}"
+ local port="${2}"
+
+ local port_hex i
+
+ port_hex="$(printf "%04X" "${port}")"
+ for i in $(seq 10); do
+ ip netns exec "${listener_ns}" cat /proc/net/tcp | \
+ awk "BEGIN {rc=1} {if (\$2 ~ /:${port_hex}\$/ && \$4 ~ /0A/) {rc=0; exit}} END {exit rc}" &&
+ break
+ sleep 0.1
+ done
+}
+
+wait_connected()
+{
+ local listener_ns="${1}"
+ local port="${2}"
+
+ local port_hex i
+
+ port_hex="$(printf "%04X" "${port}")"
+ for i in $(seq 10); do
+ ip netns exec ${listener_ns} grep -q " 0100007F:${port_hex} " /proc/net/tcp && break
+ sleep 0.1
+ done
+}

trap cleanup EXIT
ip netns add $ns
@@ -81,15 +111,15 @@ echo "a" | \
ip netns exec $ns \
./mptcp_connect -p 10000 -l -t ${timeout_poll} \
0.0.0.0 >/dev/null &
-sleep 0.1
+wait_local_port_listen $ns 10000
chk_msk_nr 0 "no msk on netns creation"

echo "b" | \
timeout ${timeout_test} \
ip netns exec $ns \
- ./mptcp_connect -p 10000 -j -t ${timeout_poll} \
+ ./mptcp_connect -p 10000 -r 0 -t ${timeout_poll} \
127.0.0.1 >/dev/null &
-sleep 0.1
+wait_connected $ns 10000
chk_msk_nr 2 "after MPC handshake "
chk_msk_remote_key_nr 2 "....chk remote_key"
chk_msk_fallback_nr 0 "....chk no fallback"
@@ -101,13 +131,13 @@ echo "a" | \
ip netns exec $ns \
./mptcp_connect -p 10001 -l -s TCP -t ${timeout_poll} \
0.0.0.0 >/dev/null &
-sleep 0.1
+wait_local_port_listen $ns 10001
echo "b" | \
timeout ${timeout_test} \
ip netns exec $ns \
- ./mptcp_connect -p 10001 -j -t ${timeout_poll} \
+ ./mptcp_connect -p 10001 -r 0 -t ${timeout_poll} \
127.0.0.1 >/dev/null &
-sleep 0.1
+wait_connected $ns 10001
chk_msk_fallback_nr 1 "check fallback"
flush_pids

@@ -119,7 +149,7 @@ for I in `seq 1 $NR_CLIENTS`; do
./mptcp_connect -p $((I+10001)) -l -w 10 \
-t ${timeout_poll} 0.0.0.0 >/dev/null &
done
-sleep 0.1
+wait_local_port_listen $ns $((NR_CLIENTS + 10001))

for I in `seq 1 $NR_CLIENTS`; do
echo "b" | \