Explicitly check for a non NULL ifp in in_control(). Only MROUTING

ioctl(2)s are an exception to this rule.  This makes clear that ifa
cannot be used initialized as found by jsg@ with gcc/clang.

ok krw@, bluhm@, jca@

diff --git a/sys/netinet/in.c b/sys/netinet/in.c
index 0e3bb35..c46d626 100644 (file)
--- a/sys/netinet/in.c
+++ b/sys/netinet/in.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: in.c,v 1.113 2014/12/19 17:14:40 tedu Exp $   */
+/*     $OpenBSD: in.c,v 1.114 2015/01/05 10:21:58 mpi Exp $    */
 /*     $NetBSD: in.c,v 1.26 1996/02/13 23:41:39 christos Exp $ */
 
 /*
@@ -175,9 +175,7 @@ in_len2mask(struct in_addr *mask, int len)
 
 /*
  * Generic internet control operations (ioctl's).
- * Ifp is 0 if not an interface-specific ioctl.
  */
-/* ARGSUSED */
 int
 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp)
 {
@@ -191,26 +189,31 @@ in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp)
        int s;
 
        switch (cmd) {
+#ifdef MROUTING
+       case SIOCGETVIFCNT:
+       case SIOCGETSGCNT:
+               return (mrt_ioctl(so, cmd, data));
+#endif /* MROUTING */
        case SIOCALIFADDR:
        case SIOCDLIFADDR:
                if ((so->so_state & SS_PRIV) == 0)
                        return (EPERM);
                /* FALLTHROUGH */
        case SIOCGLIFADDR:
-               if (!ifp)
-                       return EINVAL;
+               if (ifp == NULL)
+                       return (EINVAL);
                return in_lifaddr_ioctl(so, cmd, data, ifp);
+       default:
+               if (ifp == NULL)
+                       return (EOPNOTSUPP);
        }
 
-       /*
-        * Find address for this interface, if it exists.
-        */
-       if (ifp)
-               TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
-                       if (ifa->ifa_addr->sa_family == AF_INET) {
-                               ia = ifatoia(ifa);
-                               break;
-                       }
+       TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
+               if (ifa->ifa_addr->sa_family == AF_INET) {
+                       ia = ifatoia(ifa);
+                       break;
+               }
+       }
 
        switch (cmd) {
 
@@ -232,8 +235,6 @@ in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp)
                if ((so->so_state & SS_PRIV) == 0)
                        return (EPERM);
 
-               if (ifp == 0)
-                       panic("in_control");
                if (ia == NULL) {
                        ia = malloc(sizeof *ia, M_IFADDR, M_WAITOK | M_ZERO);
                        ia->ia_addr.sin_family = AF_INET;
@@ -391,14 +392,8 @@ in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp)
                splx(s);
                break;
 
-#ifdef MROUTING
-       case SIOCGETVIFCNT:
-       case SIOCGETSGCNT:
-               return (mrt_ioctl(so, cmd, data));
-#endif /* MROUTING */
-
        default:
-               if (ifp == 0 || ifp->if_ioctl == 0)
+               if (ifp->if_ioctl == NULL)
                        return (EOPNOTSUPP);
                return ((*ifp->if_ioctl)(ifp, cmd, data));
        }