[PATCH v2 wireless-next] wifi: mac80211: cleanup error path of ieee80211_do_open

[PATCH v2 wireless-next] wifi: mac80211: cleanup error path of ieee80211_do_open

[Miri Korenblit]

If we failed on drv_start, we currently cleanup AP_VLAN reference to
bss.
But this is not needed, since AP_VLAN must be tied to a pre-existing AP
interface, so open_count cannot be 0, so we will never call drv_start
for AP_VLAN interfaces.

Remove these cleanup and return immediately instead.

Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
---
 net/mac80211/iface.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)
---
v2: make the commit apply

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 232fc0b80e44..234de4762be5 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1361,8 +1361,6 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
 		break;
 		}
 	case NL80211_IFTYPE_AP:
-		sdata->bss = &sdata->u.ap;
-		break;
 	case NL80211_IFTYPE_MESH_POINT:
 	case NL80211_IFTYPE_STATION:
 	case NL80211_IFTYPE_MONITOR:
@@ -1387,8 +1385,13 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
 		local->reconfig_failure = false;
 
 		res = drv_start(local);
-		if (res)
-			goto err_del_bss;
+		if (res) {
+			/*
+			 * no need to worry about AP_VLAN cleanup since in that
+			 * case we can't have open_count == 0
+			 */
+			return res;
+		}
 		ieee80211_led_radio(local, true);
 		ieee80211_mod_tpt_led_trig(local,
 					   IEEE80211_TPT_LEDTRIG_FL_RADIO, 0);
@@ -1459,6 +1462,9 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
 		netif_carrier_on(dev);
 		list_add_tail_rcu(&sdata->u.mntr.list, &local->mon_list);
 		break;
+	case NL80211_IFTYPE_AP:
+		sdata->bss = &sdata->u.ap;
+		fallthrough;
 	default:
 		if (coming_up) {
 			ieee80211_del_virtual_monitor(local);
@@ -1547,10 +1553,10 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
  err_stop:
 	if (!local->open_count)
 		drv_stop(local, false);
- err_del_bss:
-	sdata->bss = NULL;
 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 		list_del(&sdata->u.vlan.list);
+	/* Might not be initialized yet, but it is harmless */
+	sdata->bss = NULL;
 	return res;
 }
 
-- 
2.34.1