[PATCH net v2 4/6] net: stmmac: selftests: Capture all packets for vlan checks

[Maxime Chevallier]

While we use vlan_vid_add to trigger the tag filtering machinery
in the driver, there's no netdev associated to the VLAN. This causes the
skb to arrive with empty skb->vlan_tci fields, as the packet is marked
OTHERHOST in __netif_receive_skb_core(), and we fail our validation.

Let's use the proxy mechanism introduced for DSA, that registers a
ETH_P_ALL packet handler that runs earlier, before the vlan netdev
lookup, then filters for the correct ethertype before passing an skb
clone to our validation function.

Fixes: 091810dbded9 ("net: stmmac: Introduce selftests support")
Signed-off-by: Maxime Chevallier <maxime.chevallier@xxxxxxxxxxx>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
index f3a533bc6bb6..ec56ee0031ab 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
@@ -241,6 +241,7 @@ struct stmmac_test_priv {
 	__be16 packet_type;
 	int (*func)(struct sk_buff *skb, struct net_device *ndev,
 		    struct packet_type *pt, struct net_device *orig_ndev);
+	bool capture_all;
 	int double_vlan;
 	int vlan_id;
 	int ok;
@@ -343,7 +344,7 @@ static void stmmac_sft_add_pack(struct packet_type *pt)
 {
 	struct stmmac_test_priv *tpriv = pt->af_packet_priv;
 
-	if (netdev_uses_dsa(tpriv->pt.dev)) {
+	if (netdev_uses_dsa(tpriv->pt.dev) || tpriv->capture_all) {
 		tpriv->packet_type = tpriv->pt.type;
 		tpriv->func = tpriv->pt.func;
 
@@ -994,6 +995,7 @@ static int __stmmac_test_vlanfilt(struct stmmac_priv *priv)
 	tpriv->pt.dev = priv->dev;
 	tpriv->pt.af_packet_priv = tpriv;
 	tpriv->packet = &attr;
+	tpriv->capture_all = true;
 
 	/*
 	 * As we use HASH filtering, false positives may appear. This is a
@@ -1088,6 +1090,7 @@ static int __stmmac_test_dvlanfilt(struct stmmac_priv *priv)
 	tpriv->pt.dev = priv->dev;
 	tpriv->pt.af_packet_priv = tpriv;
 	tpriv->packet = &attr;
+	tpriv->capture_all = true;
 
 	/*
 	 * As we use HASH filtering, false positives may appear. This is a
@@ -1366,6 +1369,7 @@ static int stmmac_test_vlanoff_common(struct stmmac_priv *priv, bool svlan)
 	tpriv->pt.af_packet_priv = tpriv;
 	tpriv->packet = &attr;
 	tpriv->vlan_id = 0x123;
+	tpriv->capture_all = true;
 	stmmac_sft_add_pack(&tpriv->pt);
 
 	ret = vlan_vid_add(priv->dev, htons(proto), tpriv->vlan_id);
-- 
2.55.0