@@ -863,6 +863,18 @@ static int macvlan_changelink(struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[])
{
struct macvlan_dev *vlan = netdev_priv(dev);
+ enum macvlan_mode mode;
+ bool set_mode = false;
+
+ /* Validate mode, but don't set yet: setting flags may fail. */
+ if (data && data[IFLA_MACVLAN_MODE]) {
+ set_mode = true;
+ mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
+ /* Passthrough mode can't be set or cleared dynamically */
+ if ((mode == MACVLAN_MODE_PASSTHRU) !=
+ (vlan->mode == MACVLAN_MODE_PASSTHRU))
+ return -EINVAL;
+ }
if (data && data[IFLA_MACVLAN_FLAGS]) {
__u16 flags = nla_get_u16(data[IFLA_MACVLAN_FLAGS]);
@@ -879,8 +891,8 @@ static int macvlan_changelink(struct net_device *dev,
}
vlan->flags = flags;
}
- if (data && data[IFLA_MACVLAN_MODE])
- vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
+ if (set_mode)
+ vlan->mode = mode;
return 0;
}
macvlan passthrough mode is special: it's not possible to switch to or from it through a netlink command. But if you try, the command will succeed, which is confusing. Validate input and return error to user. Cc: Sridhar Samudrala <sri@us.ibm.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> --- drivers/net/macvlan.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)