cfg80211/mac80211: avoid state mishmash on deauth

Avoid situation when we are on associate state in mac80211 and
on disassociate state in cfg80211. This can results on crash
during modules unload (like showed on this thread:
http://marc.info/?t=134373976300001&r=1&w=2) and possibly other
problems.

Reported-by: Pedro Francisco <pedrogfrancisco@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/cfg80211.h

@@ -1218,6 +1218,7 @@ struct cfg80211_deauth_request {
 	const u8 *ie;
 	size_t ie_len;
 	u16 reason_code;
+	bool local_state_change;
 };
 
 /**

net/mac80211/mlme.c

@@ -3549,6 +3549,7 @@ int ieee80211_mgd_deauth(struct ieee80211_sub_if_data *sdata,
 {
 	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
 	u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
+	bool tx = !req->local_state_change;
 
 	mutex_lock(&ifmgd->mtx);
 
@@ -3565,12 +3566,12 @@ int ieee80211_mgd_deauth(struct ieee80211_sub_if_data *sdata,
 	if (ifmgd->associated &&
 	    ether_addr_equal(ifmgd->associated->bssid, req->bssid)) {
 		ieee80211_set_disassoc(sdata, IEEE80211_STYPE_DEAUTH,
-				       req->reason_code, true, frame_buf);
+				       req->reason_code, tx, frame_buf);
 	} else {
 		drv_mgd_prepare_tx(sdata->local, sdata);
 		ieee80211_send_deauth_disassoc(sdata, req->bssid,
 					       IEEE80211_STYPE_DEAUTH,
-					       req->reason_code, true,
+					       req->reason_code, tx,
 					       frame_buf);
 	}
 

net/wireless/mlme.c

@@ -457,20 +457,14 @@ int __cfg80211_mlme_deauth(struct cfg80211_registered_device *rdev,
 		.reason_code = reason,
 		.ie = ie,
 		.ie_len = ie_len,
+		.local_state_change = local_state_change,
 	};
 
 	ASSERT_WDEV_LOCK(wdev);
 
-	if (local_state_change) {
-		if (wdev->current_bss &&
-		    ether_addr_equal(wdev->current_bss->pub.bssid, bssid)) {
-			cfg80211_unhold_bss(wdev->current_bss);
-			cfg80211_put_bss(&wdev->current_bss->pub);
-			wdev->current_bss = NULL;
-		}
-
+	if (local_state_change && (!wdev->current_bss ||
+	    !ether_addr_equal(wdev->current_bss->pub.bssid, bssid)))
 		return 0;
-	}
 
 	return rdev->ops->deauth(&rdev->wiphy, dev, &req);
 }