Re: [PATCH v2 net 1/3] bridge: Add a default_pvid sysfs attribute

On 2014/10/01 4:31, Vladislav Yasevich wrote:

This patch allows the user to set and retrieve default_pvid
value.  A new value can only be stored when vlan filtering
is disabled.

Signed-off-by: Vladislav Yasevich <redacted>
---

...

+int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val)
+{
+	u16 pvid = val;
+	int err = 0;
+
+	if (!pvid || pvid >= VLAN_VID_MASK)
+		return -EINVAL;

This seems to accept a large value as a valid value.
For example, ((1 << 16) + 10) will be handled as 10.
How about using "val" for this check?

+
+	if (!rtnl_trylock())
+		return restart_syscall();
+
+	if (pvid == br->default_pvid)
+		goto unlock;
+
+	/* Only allow default pvid change when filtering is disabled */
+	if (br->vlan_enabled) {
+		err = -EPERM;

Additional log message might help users know why it was rejected.

Thanks,
Toshiaki Makita