wireguard: selftests: test multiple parallel streams

stable inclusion
from stable-5.10.20
commit c7b1307fee19957c679af9a75ae03e5a24223258
bugzilla: 50608

--------------------------------

commit d5a49aa6 upstream.

In order to test ndo_start_xmit being called in parallel, explicitly add
separate tests, which should all run on different cores. This should
help tease out bugs associated with queueing up packets from different
cores in parallel. Currently, it hasn't found those types of bugs, but
given future planned work, this is a useful regression to avoid.

Fixes: e7096c13 ("net: WireGuard secure network tunnel")
Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

tools/testing/selftests/wireguard/netns.sh

@@ -39,7 +39,7 @@ ip0() { pretty 0 "ip $*"; ip -n $netns0 "$@"; }
 ip1() { pretty 1 "ip $*"; ip -n $netns1 "$@"; }
 ip2() { pretty 2 "ip $*"; ip -n $netns2 "$@"; }
 sleep() { read -t "$1" -N 1 || true; }
-waitiperf() { pretty "${1//*-}" "wait for iperf:5201 pid $2"; while [[ $(ss -N "$1" -tlpH 'sport = 5201') != *\"iperf3\",pid=$2,fd=* ]]; do sleep 0.1; done; }
+waitiperf() { pretty "${1//*-}" "wait for iperf:${3:-5201} pid $2"; while [[ $(ss -N "$1" -tlpH "sport = ${3:-5201}") != *\"iperf3\",pid=$2,fd=* ]]; do sleep 0.1; done; }
 waitncatudp() { pretty "${1//*-}" "wait for udp:1111 pid $2"; while [[ $(ss -N "$1" -ulpH 'sport = 1111') != *\"ncat\",pid=$2,fd=* ]]; do sleep 0.1; done; }
 waitiface() { pretty "${1//*-}" "wait for $2 to come up"; ip netns exec "$1" bash -c "while [[ \$(< \"/sys/class/net/$2/operstate\") != up ]]; do read -t .1 -N 0 || true; done;"; }
 
@@ -141,6 +141,19 @@ tests() {
 	n2 iperf3 -s -1 -B fd00::2 &
 	waitiperf $netns2 $!
 	n1 iperf3 -Z -t 3 -b 0 -u -c fd00::2
+
+	# TCP over IPv4, in parallel
+	for max in 4 5 50; do
+		local pids=( )
+		for ((i=0; i < max; ++i)) do
+			n2 iperf3 -p $(( 5200 + i )) -s -1 -B 192.168.241.2 &
+			pids+=( $! ); waitiperf $netns2 $! $(( 5200 + i ))
+		done
+		for ((i=0; i < max; ++i)) do
+			n1 iperf3 -Z -t 3 -p $(( 5200 + i )) -c 192.168.241.2 &
+		done
+		wait "${pids[@]}"
+	done
 }
 
 [[ $(ip1 link show dev wg0) =~ mtu\ ([0-9]+) ]] && orig_mtu="${BASH_REMATCH[1]}"