Re: [PATCH net] selftests/net: use tc rule to filter the na packet

2024-05-16 Thread Jakub Kicinski
On Tue, 14 May 2024 15:11:30 +0800 Hangbin Liu wrote:
> Hi Jakub, would you please help check if this fix the
> arp_ndisc_untracked_subnets flake issue on debug kernel?

It didn't get ingested by the CI because there's a conflict with
something else that got merged into lib.sh. Could you rebase / repost?


At a glance the problem in the CI is that it times out on debug kernels:

# overriding timeout to 7200
# selftests: net: arp_ndisc_untracked_subnets.sh
# TEST: test_arp:  accept_arp=0   [ OK ]
# TEST: test_arp:  accept_arp=1   [ OK ]
# TEST: test_arp:  accept_arp=2  same_subnet=0[ OK ]
# TEST: test_arp:  accept_arp=2  same_subnet=1[ OK ]
#
not ok 1 selftests: net: arp_ndisc_untracked_subnets.sh # TIMEOUT 7200 seconds

So it consumed full 2 hours and didn't finish.



[PATCH net] selftests/net: use tc rule to filter the na packet

2024-05-14 Thread Hangbin Liu
Test arp_ndisc_untracked_subnets use tcpdump to filter the unsolicited
and untracked na messages. It set -e before calling tcpdump. But if
tcpdump filters 0 packet, it will return none zero, and cause the script
to exit.

Instead of using slow tcpdump to capture packets, let's using tc rule
to filter out the na message.

At the same time, fix function setup_v6 which only needs one parameter.
Move all the related helpers from forwarding lib.sh to net lib.sh.

Fixes: 0ea7b0a454ca ("selftests: net: arp_ndisc_untracked_subnets: test for 
arp_accept and accept_untracked_na")
Signed-off-by: Hangbin Liu 
---

Hi Jakub, would you please help check if this fix the
arp_ndisc_untracked_subnets flake issue on debug kernel?

---
 .../net/arp_ndisc_untracked_subnets.sh| 53 +
 tools/testing/selftests/net/forwarding/lib.sh | 76 ---
 tools/testing/selftests/net/lib.sh| 76 +++
 3 files changed, 93 insertions(+), 112 deletions(-)

diff --git a/tools/testing/selftests/net/arp_ndisc_untracked_subnets.sh 
b/tools/testing/selftests/net/arp_ndisc_untracked_subnets.sh
index a40c0e9bd023..eef5cbf6eecc 100755
--- a/tools/testing/selftests/net/arp_ndisc_untracked_subnets.sh
+++ b/tools/testing/selftests/net/arp_ndisc_untracked_subnets.sh
@@ -73,25 +73,19 @@ setup_v6() {
# namespaces. veth0 is veth-router, veth1 is veth-host.
# first, set up the inteface's link to the namespace
# then, set the interface "up"
-   ip -6 -netns ${ROUTER_NS_V6} link add name ${ROUTER_INTF} \
-   type veth peer name ${HOST_INTF}
-
-   ip -6 -netns ${ROUTER_NS_V6} link set dev ${ROUTER_INTF} up
-   ip -6 -netns ${ROUTER_NS_V6} link set dev ${HOST_INTF} netns \
-   ${HOST_NS_V6}
+   ip -n ${ROUTER_NS_V6} link add name ${ROUTER_INTF} \
+   type veth peer name ${HOST_INTF} netns ${HOST_NS_V6}
 
-   ip -6 -netns ${HOST_NS_V6} link set dev ${HOST_INTF} up
-   ip -6 -netns ${ROUTER_NS_V6} addr add \
-   ${ROUTER_ADDR_V6}/${PREFIX_WIDTH_V6} dev ${ROUTER_INTF} nodad
+   # Add tc rule to filter out host na message
+   tc -n ${ROUTER_NS_V6} qdisc add dev ${ROUTER_INTF} clsact
+   tc -n ${ROUTER_NS_V6} filter add dev ${ROUTER_INTF} \
+   ingress protocol ipv6 pref 1 handle 101 \
+   flower src_ip ${HOST_ADDR_V6} ip_proto icmpv6 type 136 skip_hw 
action pass
 
HOST_CONF=net.ipv6.conf.${HOST_INTF}
ip netns exec ${HOST_NS_V6} sysctl -qw ${HOST_CONF}.ndisc_notify=1
ip netns exec ${HOST_NS_V6} sysctl -qw ${HOST_CONF}.disable_ipv6=0
-   ip -6 -netns ${HOST_NS_V6} addr add ${HOST_ADDR_V6}/${PREFIX_WIDTH_V6} \
-   dev ${HOST_INTF}
-
ROUTER_CONF=net.ipv6.conf.${ROUTER_INTF}
-
ip netns exec ${ROUTER_NS_V6} sysctl -w \
${ROUTER_CONF}.forwarding=1 >/dev/null 2>&1
ip netns exec ${ROUTER_NS_V6} sysctl -w \
@@ -99,6 +93,13 @@ setup_v6() {
ip netns exec ${ROUTER_NS_V6} sysctl -w \
${ROUTER_CONF}.accept_untracked_na=${accept_untracked_na} \
>/dev/null 2>&1
+
+   ip -n ${ROUTER_NS_V6} link set dev ${ROUTER_INTF} up
+   ip -n ${HOST_NS_V6} link set dev ${HOST_INTF} up
+   ip -n ${ROUTER_NS_V6} addr add ${ROUTER_ADDR_V6}/${PREFIX_WIDTH_V6} \
+   dev ${ROUTER_INTF} nodad
+   ip -n ${HOST_NS_V6} addr add ${HOST_ADDR_V6}/${PREFIX_WIDTH_V6} \
+   dev ${HOST_INTF}
set +e
 }
 
@@ -162,26 +163,6 @@ arp_test_gratuitous_combinations() {
arp_test_gratuitous 2 1
 }
 
-cleanup_tcpdump() {
-   set -e
-   [[ ! -z  ${tcpdump_stdout} ]] && rm -f ${tcpdump_stdout}
-   [[ ! -z  ${tcpdump_stderr} ]] && rm -f ${tcpdump_stderr}
-   tcpdump_stdout=
-   tcpdump_stderr=
-   set +e
-}
-
-start_tcpdump() {
-   set -e
-   tcpdump_stdout=`mktemp`
-   tcpdump_stderr=`mktemp`
-   ip netns exec ${ROUTER_NS_V6} timeout 15s \
-   tcpdump --immediate-mode -tpni ${ROUTER_INTF} -c 1 \
-   "icmp6 && icmp6[0] == 136 && src ${HOST_ADDR_V6}" \
-   > ${tcpdump_stdout} 2> /dev/null
-   set +e
-}
-
 verify_ndisc() {
local accept_untracked_na=$1
local same_subnet=$2
@@ -222,8 +203,9 @@ ndisc_test_untracked_advertisements() {
HOST_ADDR_V6=2001:db8:abcd:0012::3
fi
fi
-   setup_v6 $1 $2
-   start_tcpdump
+   setup_v6 $1
+   slowwait_for_counter 15 1 \
+   tc_rule_handle_stats_get "dev ${ROUTER_INTF} ingress" 101 
".packets" "-n ${ROUTER_NS_V6}"
 
if verify_ndisc $1 $2; then
printf "TEST: %-60s  [ OK ]\n" "${test_msg[*]}"
@@ -231,7 +213,6 @@ ndisc_test_untracked_advertisements() {
printf "TEST: %-60s  [FAIL]\n" "${test_msg[*]}"
fi
 
-   cleanup_tcpdump
cleanup_v6
set +e
 }
diff --git