* [PATCH v2 net-next 1/2] netdevsim: tc: allow to test nf_tables offload control plane code
2026-06-12 9:22 [PATCH v2 net-next 0/2] netdevsim: add fake FT/CLS_FLOWER offload Florian Westphal
@ 2026-06-12 9:22 ` Florian Westphal
2026-06-12 9:22 ` [PATCH v2 net-next 2/2] selftests: netfilter: add phony nft_offload test Florian Westphal
1 sibling, 0 replies; 3+ messages in thread
From: Florian Westphal @ 2026-06-12 9:22 UTC (permalink / raw)
To: netdev
Cc: Paolo Abeni, David S. Miller, Eric Dumazet, Jakub Kicinski,
netfilter-devel, pablo
The actual 'offload' is phony, all commands are ignored: this is only
useful to test control plane code.
Tag the existing callback to permit error injection to test rollback/abort
code in nf_tables. This is also for fuzzers - the fault injection
framework allows probabilistic error insertion.
Signed-off-by: Florian Westphal <fw@strlen.de>
---
v2: move extack error to nsim_setup_tc_block_cb
drivers/net/netdevsim/bpf.c | 6 ------
drivers/net/netdevsim/tc.c | 20 +++++++++++++++++++-
2 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c
index 8eebcc933ddb..16aa88278398 100644
--- a/drivers/net/netdevsim/bpf.c
+++ b/drivers/net/netdevsim/bpf.c
@@ -123,12 +123,6 @@ int nsim_bpf_setup_tc_block_cb(enum tc_setup_type type,
struct netdevsim *ns = cb_priv;
struct bpf_prog *oldprog;
- if (type != TC_SETUP_CLSBPF) {
- NSIM_EA(cls_bpf->common.extack,
- "only offload of BPF classifiers supported");
- return -EOPNOTSUPP;
- }
-
if (!tc_cls_can_offload_and_chain0(ns->netdev, &cls_bpf->common))
return -EOPNOTSUPP;
diff --git a/drivers/net/netdevsim/tc.c b/drivers/net/netdevsim/tc.c
index 8f013a5895a2..a415e02a6df1 100644
--- a/drivers/net/netdevsim/tc.c
+++ b/drivers/net/netdevsim/tc.c
@@ -9,7 +9,22 @@
static int
nsim_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void *cb_priv)
{
- return nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
+ struct flow_cls_common_offload *common = type_data;
+ int err = 0;
+
+ switch (type) {
+ case TC_SETUP_CLSBPF:
+ err = nsim_bpf_setup_tc_block_cb(type, type_data, cb_priv);
+ break;
+ case TC_SETUP_CLSFLOWER:
+ break;
+ default:
+ NSIM_EA(common->extack, "offload type not supported");
+ err = -EOPNOTSUPP;
+ break;
+ }
+
+ return err;
}
static void nsim_taprio_stats(struct tc_taprio_qopt_stats *stats)
@@ -73,7 +88,10 @@ nsim_setup_tc(struct net_device *dev, enum tc_setup_type type, void *type_data)
&nsim_block_cb_list,
nsim_setup_tc_block_cb,
ns, ns, true);
+ case TC_SETUP_FT:
+ return 0;
default:
return -EOPNOTSUPP;
}
}
+ALLOW_ERROR_INJECTION(nsim_setup_tc, ERRNO);
--
2.53.0
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH v2 net-next 2/2] selftests: netfilter: add phony nft_offload test
2026-06-12 9:22 [PATCH v2 net-next 0/2] netdevsim: add fake FT/CLS_FLOWER offload Florian Westphal
2026-06-12 9:22 ` [PATCH v2 net-next 1/2] netdevsim: tc: allow to test nf_tables offload control plane code Florian Westphal
@ 2026-06-12 9:22 ` Florian Westphal
1 sibling, 0 replies; 3+ messages in thread
From: Florian Westphal @ 2026-06-12 9:22 UTC (permalink / raw)
To: netdev
Cc: Paolo Abeni, David S. Miller, Eric Dumazet, Jakub Kicinski,
netfilter-devel, pablo
... "phony", because its not testing offloads, it tests the control
plane code. Also test error unwind via fault injection framework.
For a proper test, real hardware would be required given we'd have
check if 'previously handed off to hardware' offload commands are
properly removed again on failure or rule flush.
Signed-off-by: Florian Westphal <fw@strlen.de>
---
v2: sort config
shellcheck fixups
.../testing/selftests/net/netfilter/Makefile | 1 +
tools/testing/selftests/net/netfilter/config | 6 +
.../selftests/net/netfilter/nft_offload.sh | 132 ++++++++++++++++++
3 files changed, 139 insertions(+)
create mode 100755 tools/testing/selftests/net/netfilter/nft_offload.sh
diff --git a/tools/testing/selftests/net/netfilter/Makefile b/tools/testing/selftests/net/netfilter/Makefile
index d953ee218c0f..f88dd4ef8d26 100644
--- a/tools/testing/selftests/net/netfilter/Makefile
+++ b/tools/testing/selftests/net/netfilter/Makefile
@@ -32,6 +32,7 @@ TEST_PROGS := \
nft_meta.sh \
nft_nat.sh \
nft_nat_zones.sh \
+ nft_offload.sh \
nft_queue.sh \
nft_synproxy.sh \
nft_tproxy_tcp.sh \
diff --git a/tools/testing/selftests/net/netfilter/config b/tools/testing/selftests/net/netfilter/config
index 979cff56e1f5..c3c121b6f300 100644
--- a/tools/testing/selftests/net/netfilter/config
+++ b/tools/testing/selftests/net/netfilter/config
@@ -11,7 +11,12 @@ CONFIG_BRIDGE_NF_EBTABLES_LEGACY=m
CONFIG_BRIDGE_VLAN_FILTERING=y
CONFIG_CGROUP_BPF=y
CONFIG_CRYPTO_SHA1=m
+CONFIG_DEBUG_FS=y
CONFIG_DUMMY=m
+CONFIG_FAIL_FUNCTION=y
+CONFIG_FAULT_INJECTION=y
+CONFIG_FAULT_INJECTION_DEBUG_FS=y
+CONFIG_FUNCTION_ERROR_INJECTION=y
CONFIG_INET_DIAG=m
CONFIG_INET_ESP=m
CONFIG_INET_SCTP_DIAG=m
@@ -36,6 +41,7 @@ CONFIG_IP_VS_RR=m
CONFIG_MACVLAN=m
CONFIG_NAMESPACES=y
CONFIG_NET_CLS_U32=m
+CONFIG_NETDEVSIM=m
CONFIG_NETFILTER=y
CONFIG_NETFILTER_ADVANCED=y
CONFIG_NETFILTER_NETLINK=m
diff --git a/tools/testing/selftests/net/netfilter/nft_offload.sh b/tools/testing/selftests/net/netfilter/nft_offload.sh
new file mode 100755
index 000000000000..859bdedf1a51
--- /dev/null
+++ b/tools/testing/selftests/net/netfilter/nft_offload.sh
@@ -0,0 +1,132 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+source lib.sh
+
+checktool "nft --version" "run test without nft tool"
+modprobe -q netdevsim
+
+sysfs="/sys/kernel/debug/fail_function"
+failname="/proc/self/make-it-fail"
+duration=30
+fault=0
+ret=0
+file_ft=""
+file_rs=""
+id=$((RANDOM%65536))
+
+read -r t < /proc/sys/kernel/tainted
+if [ "$t" -ne 0 ];then
+ echo SKIP: kernel is tainted
+ exit $ksft_skip
+fi
+
+cleanup() {
+ cleanup_netdevsim "$id" "$NS"
+ cleanup_ns "$NS"
+ [ "$fault" -eq 1 ] && echo '!nsim_setup_tc' > "$sysfs/inject"
+ rm -f "$file_ft" "$file_rs"
+}
+trap cleanup EXIT
+
+skip() {
+ echo "SKIP: $*"
+ [ $ret -eq 0 ] && exit 4
+
+ exit $ret
+}
+
+set -e
+setup_ns NS
+
+create_netdevsim "$id" "$NS" >/dev/null
+nsim_port=$(create_netdevsim_port "$id" "$NS" 2)
+
+file_ft=$(mktemp)
+cat > "$file_ft" <<EOF
+flush ruleset
+table inet t {
+ flowtable f {
+ flags offload
+ hook ingress priority filter + 10
+ devices = { "$nsim_port", "dummyf1" }
+ }
+
+ chain cf {
+ type filter hook forward priority 0; policy accept;
+ ct state new meta l4proto tcp flow add @f
+ }
+}
+EOF
+
+if ip netns exec "$NS" nft -f "$file_ft"; then
+ echo "PASS: flowtable offload"
+else
+ echo "FAIL: flowtable offload"
+ ret=1
+fi
+
+file_rs=$(mktemp)
+cat > "$file_rs" <<EOF
+table netdev t {
+ chain c {
+ type filter hook ingress device $nsim_port priority 1
+ flags offload
+ ip saddr 10.2.1.1 ip daddr 10.2.1.2 ip protocol icmp accept
+ ip saddr 10.2.1.1 ip daddr 10.2.1.3 ip protocol icmp drop
+ ip saddr 10.2.1.0/24 ip daddr 10.2.1.0/24 ip protocol icmp accept
+ ip6 saddr dead:beef::1 ip6 daddr dead:beef::2 meta l4proto ipv6-icmp accept
+ ip6 saddr dead:beef::1 ip6 daddr dead:beef::3 meta l4proto ipv6-icmp drop
+ ip6 saddr dead:beef::/64 ip6 daddr dead:beef::/64 meta l4proto ipv6-icmp accept
+ }
+}
+EOF
+if ip netns exec "$NS" nft -f "$file_rs"; then
+ echo "PASS: ruleset offload"
+else
+ echo "FAIL: ruleset offload"
+ ret=1
+fi
+
+test -d "$sysfs" || skip "$sysfs not present"
+grep -q nsim_setup_tc "$sysfs/injectable" || skip "nsim_setup_tc fault injection not available"
+
+echo Y > "$sysfs/task-filter"
+echo 0 > "$sysfs/verbose"
+echo "nsim_setup_tc" > "$sysfs/inject"
+fault=1
+
+p=$(((RANDOM%90) + 10))
+echo $p > "$sysfs/probability"
+echo -1 > "$sysfs/times"
+
+count=0
+ok=0
+
+now=$(date +%s)
+stop=$((now+duration))
+
+# fault-injection enabled rule loads are expected to fail.
+set +e
+while [ "$now" -le "$stop" ]; do
+ for f in "$file_ft" "$file_rs"; do
+ if ip netns exec "$NS" bash -c "echo 1 > $failname ; ip netns exec \"$NS\" nft -f $f" 2> /dev/null;then
+ ok=$((ok+1))
+ fi
+ count=$((count+1))
+ done
+ now=$(date +%s)
+done
+
+sleep 5
+
+read -r t < /proc/sys/kernel/tainted
+if [ "$t" -eq 0 ];then
+ echo "PASS: Not tainted. $count rounds, $ok successful ruleset loads with P $p."
+else
+ echo "ERROR: Tainted. $count rounds, $ok successful ruleset loads with P $p."
+ dmesg
+ ret=1
+fi
+
+exit $ret
--
2.53.0
^ permalink raw reply related [flat|nested] 3+ messages in thread