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 <s...@us.ibm.com> Cc: "David S. Miller" <da...@davemloft.net> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> --- drivers/net/macvlan.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c index 18373b6..13937f9 100644 --- a/drivers/net/macvlan.c +++ b/drivers/net/macvlan.c @@ -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; } -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/