BRCM_LEG_PORT_ID was incorrectly used for pskb_may_pull length.
The correct check is BRCM_LEG_TAG_LEN + VLAN_HLEN, or 10 bytes.

Fixes: 964dbf186eaa ("net: dsa: tag_brcm: add support for legacy tags")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---
 net/dsa/tag_brcm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/dsa/tag_brcm.c b/net/dsa/tag_brcm.c
index 8c3c068728e5..fe75821623a4 100644
--- a/net/dsa/tag_brcm.c
+++ b/net/dsa/tag_brcm.c
@@ -257,7 +257,7 @@ static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
 	int source_port;
 	u8 *brcm_tag;
 
-	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_PORT_ID)))
+	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_TAG_LEN + VLAN_HLEN)))
 		return NULL;
 
 	brcm_tag = dsa_etype_header_pos_rx(skb);
-- 
2.39.5

On 5/29/2025 5:44 AM, Álvaro Fernández Rojas wrote:
> BRCM_LEG_PORT_ID was incorrectly used for pskb_may_pull length.
> The correct check is BRCM_LEG_TAG_LEN + VLAN_HLEN, or 10 bytes.
> 
> Fixes: 964dbf186eaa ("net: dsa: tag_brcm: add support for legacy tags")
> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
-- 
Florian