Correctly state the link state to INVALID when creating a carp interface.

Since vhe are allocated with M_ZERO and INIT is also defined to be 0,
carp_set_state() would result in a no-op because of the state check.

So explicitly initialize the state of a vhe to INIT and move the state
check in carp_set_state_all() to prevent similar issues in the future.

Problem and initial diff from Johan Ymerson, thanks!

ok henning@

diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
index 76185eb..310b0ce 100644 (file)
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ip_carp.c,v 1.256 2015/05/15 11:53:06 claudio Exp $   */
+/*     $OpenBSD: ip_carp.c,v 1.257 2015/05/21 09:17:53 mpi Exp $       */
 
 /*
  * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
@@ -708,9 +708,7 @@ carpattach(int n)
 }
 
 int
-carp_clone_create(ifc, unit)
-       struct if_clone *ifc;
-       int unit;
+carp_clone_create(struct if_clone *ifc, int unit)
 {
        struct carp_softc *sc;
        struct ifnet *ifp;
@@ -753,11 +751,11 @@ carp_clone_create(ifc, unit)
        ifp->if_sadl->sdl_type = IFT_CARP;
        ifp->if_output = carp_output;
        ifp->if_priority = IF_CARP_DEFAULT_PRIORITY;
+       ifp->if_link_state = LINK_STATE_INVALID;
 
        /* Hook carp_addr_updated to cope with address and route changes. */
        sc->ah_cookie = hook_establish(sc->sc_if.if_addrhooks, 0,
            carp_addr_updated, sc);
-       carp_set_state_all(sc, INIT);
 
        return (0);
 }
@@ -774,6 +772,7 @@ carp_new_vhost(struct carp_softc *sc, int vhid, int advskew)
        vhe->parent_sc = sc;
        vhe->vhid = vhid;
        vhe->advskew = advskew;
+       vhe->state = INIT;
        timeout_set(&vhe->ad_tmo, carp_send_ad, vhe);
        timeout_set(&vhe->md_tmo, carp_master_down, vhe);
        timeout_set(&vhe->md6_tmo, carp_master_down, vhe);
@@ -2276,8 +2275,12 @@ carp_set_state_all(struct carp_softc *sc, int state)
 {
        struct carp_vhost_entry *vhe;
 
-       LIST_FOREACH(vhe, &sc->carp_vhosts, vhost_entries)
+       LIST_FOREACH(vhe, &sc->carp_vhosts, vhost_entries) {
+               if (vhe->state == state)
+                       continue;
+
                carp_set_state(vhe, state);
+       }
 }
 
 void
@@ -2287,8 +2290,8 @@ carp_set_state(struct carp_vhost_entry *vhe, int state)
        static const char *carp_states[] = { CARP_STATES };
        int loglevel;
 
-       if (vhe->state == state)
-               return;
+       KASSERT(vhe->state != state);
+
        if (vhe->state == INIT || state == INIT)
                loglevel = LOG_WARNING;
        else