octeon_ep: Validate the VF ID

JIRA: https://issues.redhat.com/browse/RHEL-113707

commit af82e85
Author: Kamal Heib <kheib@redhat.com>
Date:   Thu Sep 11 18:36:10 2025 -0400

    octeon_ep: Validate the VF ID

    Add a helper to validate the VF ID and use it in the VF ndo ops to
    prevent accessing out-of-range entries.

    Without this check, users can run commands such as:

     # ip link show dev enp135s0
     2: enp135s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
        link/ether 00:00:00:01:01:00 brd ff:ff:ff:ff:ff:ff
        vf 0     link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state enable, trust off
        vf 1     link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state enable, trust off
     # ip link set dev enp135s0 vf 4 mac 00:00:00:00:00:14
     # echo $?
     0

    even though VF 4 does not exist, which results in silent success instead
    of returning an error.

    Fixes: 8a241ef ("octeon_ep: add ndo ops for VFs in PF driver")
    Signed-off-by: Kamal Heib <kheib@redhat.com>
    Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
    Reviewed-by: Simon Horman <horms@kernel.org>
    Link: https://patch.msgid.link/20250911223610.1803144-1-kheib@redhat.com
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Signed-off-by: Kamal Heib <kheib@redhat.com>

Author: Kamalheib

drivers/net/ethernet/marvell/octeon_ep/octep_main.c

@@ -1124,11 +1124,24 @@ static int octep_set_features(struct net_device *dev, netdev_features_t features
 	return err;
 }
 
+static bool octep_is_vf_valid(struct octep_device *oct, int vf)
+{
+	if (vf >= CFG_GET_ACTIVE_VFS(oct->conf)) {
+		netdev_err(oct->netdev, "Invalid VF ID %d\n", vf);
+		return false;
+	}
+
+	return true;
+}
+
 static int octep_get_vf_config(struct net_device *dev, int vf,
 			       struct ifla_vf_info *ivi)
 {
 	struct octep_device *oct = netdev_priv(dev);
 
+	if (!octep_is_vf_valid(oct, vf))
+		return -EINVAL;
+
 	ivi->vf = vf;
 	ether_addr_copy(ivi->mac, oct->vf_info[vf].mac_addr);
 	ivi->spoofchk = true;
@@ -1143,6 +1156,9 @@ static int octep_set_vf_mac(struct net_device *dev, int vf, u8 *mac)
 	struct octep_device *oct = netdev_priv(dev);
 	int err;
 
+	if (!octep_is_vf_valid(oct, vf))
+		return -EINVAL;
+
 	if (!is_valid_ether_addr(mac)) {
 		dev_err(&oct->pdev->dev, "Invalid  MAC Address %pM\n", mac);
 		return -EADDRNOTAVAIL;