nl80211: Filter unexpected interface added/up events

It looks like a RTM_NEWLINK event claiming the interface to be UP is
delivered just before removing an interface after having first indicated
that the interface was going down/removed. Ignore this event if the
interface is not present anymore at the moment the event is processed.
This fixes issues where an interface that was re-added after being
removed did not get reconfigured properly.

Signed-hostap: Jouni Malinen <j@w1.fi>
intended-for: hostap-1

diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
index 389080d..184b26f 100644 (file)
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -783,10 +783,28 @@ static void wpa_driver_nl80211_event_link(struct wpa_driver_nl80211_data *drv,
                   del ? "removed" : "added");
 
        if (os_strcmp(drv->first_bss.ifname, event.interface_status.ifname) == 0) {
-               if (del)
+               if (del) {
+                       if (drv->if_removed) {
+                               wpa_printf(MSG_DEBUG, "nl80211: if_removed "
+                                          "already set - ignore event");
+                               return;
+                       }
                        drv->if_removed = 1;
-               else
+               } else {
+                       if (if_nametoindex(drv->first_bss.ifname) == 0) {
+                               wpa_printf(MSG_DEBUG, "nl80211: Interface %s "
+                                          "does not exist - ignore "
+                                          "RTM_NEWLINK",
+                                          drv->first_bss.ifname);
+                               return;
+                       }
+                       if (!drv->if_removed) {
+                               wpa_printf(MSG_DEBUG, "nl80211: if_removed "
+                                          "already cleared - ignore event");
+                               return;
+                       }
                        drv->if_removed = 0;
+               }
        }
 
        wpa_supplicant_event(drv->ctx, EVENT_INTERFACE_STATUS, &event);
@@ -903,6 +921,14 @@ static void wpa_driver_nl80211_event_rtm_newlink(void *ctx,
                        wpa_printf(MSG_DEBUG, "nl80211: Ignore interface up "
                                   "event since interface %s is down",
                                   namebuf);
+               } else if (if_nametoindex(drv->first_bss.ifname) == 0) {
+                       wpa_printf(MSG_DEBUG, "nl80211: Ignore interface up "
+                                  "event since interface %s does not exist",
+                                  drv->first_bss.ifname);
+               } else if (drv->if_removed) {
+                       wpa_printf(MSG_DEBUG, "nl80211: Ignore interface up "
+                                  "event since interface %s is marked "
+                                  "removed", drv->first_bss.ifname);
                } else {
                        wpa_printf(MSG_DEBUG, "nl80211: Interface up");
                        drv->if_disabled = 0;