diff mbox series

[net,1/3] selftests: forwarding: fix flood_unicast_test when h2 supports IFF_UNICAST_FLT

Message ID 20220703073626.937785-2-vladimir.oltean@nxp.com (mailing list archive)
State Accepted
Commit b8e629b05f5d23f9649c901bef09fab8b0c2e4b9
Headers show
Series Fix bridge_vlan_aware.sh and bridge_vlan_unaware.sh with IFF_UNICAST_FLT | expand

Commit Message

Vladimir Oltean July 3, 2022, 7:36 a.m. UTC
As mentioned in the blamed commit, flood_unicast_test() works by
checking the match count on a tc filter placed on the receiving
interface.

But the second host interface (host2_if) has no interest in receiving a
packet with MAC DA de:ad:be:ef:13:37, so its RX filter drops it even
before the ingress tc filter gets to be executed. So we will incorrectly
get the message "Packet was not flooded when should", when in fact, the
packet was flooded as expected but dropped due to an unrelated reason,
at some other layer on the receiving side.

Force h2 to accept this packet by temporarily placing it in promiscuous
mode. Alternatively we could either deliver to its MAC address or use
tcpdump_start, but this has the fewest complications.

This fixes the "flooding" test from bridge_vlan_aware.sh and
bridge_vlan_unaware.sh, which calls flood_test from the lib.

Fixes: 236dd50bf67a ("selftests: forwarding: Add a test for flooded traffic")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 tools/testing/selftests/net/forwarding/lib.sh | 2 ++
 1 file changed, 2 insertions(+)

Comments

Ido Schimmel July 3, 2022, 10:02 a.m. UTC | #1
On Sun, Jul 03, 2022 at 10:36:24AM +0300, Vladimir Oltean wrote:
> As mentioned in the blamed commit, flood_unicast_test() works by
> checking the match count on a tc filter placed on the receiving
> interface.
> 
> But the second host interface (host2_if) has no interest in receiving a
> packet with MAC DA de:ad:be:ef:13:37, so its RX filter drops it even
> before the ingress tc filter gets to be executed. So we will incorrectly
> get the message "Packet was not flooded when should", when in fact, the
> packet was flooded as expected but dropped due to an unrelated reason,
> at some other layer on the receiving side.
> 
> Force h2 to accept this packet by temporarily placing it in promiscuous
> mode. Alternatively we could either deliver to its MAC address or use
> tcpdump_start, but this has the fewest complications.
> 
> This fixes the "flooding" test from bridge_vlan_aware.sh and
> bridge_vlan_unaware.sh, which calls flood_test from the lib.
> 
> Fixes: 236dd50bf67a ("selftests: forwarding: Add a test for flooded traffic")
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Ido Schimmel <idosch@nvidia.com>
diff mbox series

Patch

diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh
index 37ae49d47853..4e69497f021f 100755
--- a/tools/testing/selftests/net/forwarding/lib.sh
+++ b/tools/testing/selftests/net/forwarding/lib.sh
@@ -1306,6 +1306,7 @@  flood_test_do()
 
 	# Add an ACL on `host2_if` which will tell us whether the packet
 	# was flooded to it or not.
+	ip link set $host2_if promisc on
 	tc qdisc add dev $host2_if ingress
 	tc filter add dev $host2_if ingress protocol ip pref 1 handle 101 \
 		flower dst_mac $mac action drop
@@ -1323,6 +1324,7 @@  flood_test_do()
 
 	tc filter del dev $host2_if ingress protocol ip pref 1 handle 101 flower
 	tc qdisc del dev $host2_if ingress
+	ip link set $host2_if promisc off
 
 	return $err
 }