Push kernel lock into in6_ioctl()

[Klemens Nanni]

Mechanical move that "unlocks" the errno(2) cases.

This is another step towards more read-only interface ioctls running
with the shared net lock alone.
    
Feedback? OK?

diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
index 3fe9386f8af..47a381a1065 100644
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -213,9 +213,7 @@ in6_control(struct socket *so, u_long cmd, caddr_t data, 
struct ifnet *ifp)
                break;
 #endif /* MROUTING */
        default:
-               KERNEL_LOCK();
                error = in6_ioctl(cmd, data, ifp, privileged);
-               KERNEL_UNLOCK();
                break;
        }
 
@@ -225,23 +223,34 @@ in6_control(struct socket *so, u_long cmd, caddr_t data, 
struct ifnet *ifp)
 int
 in6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, int privileged)
 {
+       int error;
+
        if (ifp == NULL)
                return (ENXIO);
 
        switch (cmd) {
        case SIOCGIFINFO_IN6:
        case SIOCGNBRINFO_IN6:
-               return (nd6_ioctl(cmd, data, ifp));
+               KERNEL_LOCK();
+               error = nd6_ioctl(cmd, data, ifp);
+               KERNEL_UNLOCK();
+               return (error);
        case SIOCGIFDSTADDR_IN6:
        case SIOCGIFNETMASK_IN6:
        case SIOCGIFAFLAG_IN6:
        case SIOCGIFALIFETIME_IN6:
-               return (in6_ioctl_get(cmd, data, ifp));
+               KERNEL_LOCK();
+               error = in6_ioctl_get(cmd, data, ifp);
+               KERNEL_UNLOCK();
+               return (error);
        case SIOCAIFADDR_IN6:
        case SIOCDIFADDR_IN6:
                if (!privileged)
                        return (EPERM);
-               return (in6_ioctl_change_ifaddr(cmd, data, ifp));
+               KERNEL_LOCK();
+               error = in6_ioctl_change_ifaddr(cmd, data, ifp);
+               KERNEL_UNLOCK();
+               return (error);
        case SIOCSIFADDR:
        case SIOCSIFDSTADDR:
        case SIOCSIFBRDADDR: