wifi: cfg80211: remove BSS pointer from cfg80211_disassoc_request

The race described by the comment in mac80211 hasn't existed
since the locking rework to use the same lock and for MLO we
need to pass the AP MLD address, so just pass the BSSID or
AP MLD address instead of the BSS struct pointer, and adjust
all the code accordingly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

4 files changed, 10 insertions, 19 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index b71de89d9734..a2b4536c3a24 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -6426,18 +6426,14 @@ int ieee80211_mgd_disassoc(struct ieee80211_sub_if_data *sdata,
 {
 	u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
 
-	/*
-	 * cfg80211 should catch this ... but it's racy since
-	 * we can receive a disassoc frame, process it, hand it
-	 * to cfg80211 while that's in a locked section already
-	 * trying to tell us that the user wants to disconnect.
-	 */
-	if (sdata->deflink.u.mgd.bss != req->bss)
-		return -ENOLINK;
+	if (!sdata->u.mgd.associated ||
+	    memcmp(sdata->vif.cfg.ap_addr, req->ap_addr, ETH_ALEN))
+		return -ENOTCONN;
 
 	sdata_info(sdata,
 		   "disassociating from %pM by local choice (Reason: %u=%s)\n",
-		   req->bss->bssid, req->reason_code, ieee80211_get_reason_code_string(req->reason_code));
+		   req->ap_addr, req->reason_code,
+		   ieee80211_get_reason_code_string(req->reason_code));
 
 	ieee80211_set_disassoc(sdata, IEEE80211_STYPE_DISASSOC,
 			       req->reason_code, !req->local_state_change,
diff --git a/net/wireless/core.h b/net/wireless/core.h
index fd723fa5e2d7..e72ca6eefafb 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -372,7 +372,7 @@ int cfg80211_mlme_deauth(struct cfg80211_registered_device *rdev,
 			 const u8 *ie, int ie_len, u16 reason,
 			 bool local_state_change);
 int cfg80211_mlme_disassoc(struct cfg80211_registered_device *rdev,
-			   struct net_device *dev, const u8 *bssid,
+			   struct net_device *dev, const u8 *ap_addr,
 			   const u8 *ie, int ie_len, u16 reason,
 			   bool local_state_change);
 void cfg80211_mlme_down(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 935537c64ed8..4a35b3559daa 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -370,7 +370,7 @@ int cfg80211_mlme_deauth(struct cfg80211_registered_device *rdev,
 }
 
 int cfg80211_mlme_disassoc(struct cfg80211_registered_device *rdev,
-			   struct net_device *dev, const u8 *bssid,
+			   struct net_device *dev, const u8 *ap_addr,
 			   const u8 *ie, int ie_len, u16 reason,
 			   bool local_state_change)
 {
@@ -380,6 +380,7 @@ int cfg80211_mlme_disassoc(struct cfg80211_registered_device *rdev,
 		.local_state_change = local_state_change,
 		.ie = ie,
 		.ie_len = ie_len,
+		.ap_addr = ap_addr,
 	};
 	int err;
 
@@ -388,10 +389,7 @@ int cfg80211_mlme_disassoc(struct cfg80211_registered_device *rdev,
 	if (!wdev->connected)
 		return -ENOTCONN;
 
-	if (ether_addr_equal(wdev->links[0].client.current_bss->pub.bssid,
-			     bssid))
-		req.bss = &wdev->links[0].client.current_bss->pub;
-	else
+	if (memcmp(wdev->u.client.connected_addr, ap_addr, ETH_ALEN))
 		return -ENOTCONN;
 
 	err = rdev_disassoc(rdev, dev, &req);
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index c50e8a04199e..4316d3dc31ea 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -1318,10 +1318,7 @@ TRACE_EVENT(rdev_disassoc,
 	TP_fast_assign(
 		WIPHY_ASSIGN;
 		NETDEV_ASSIGN;
-		if (req->bss)
-			MAC_ASSIGN(bssid, req->bss->bssid);
-		else
-			eth_zero_addr(__entry->bssid);
+		MAC_ASSIGN(bssid, req->ap_addr);
 		__entry->reason_code = req->reason_code;
 		__entry->local_state_change = req->local_state_change;
 	),