wifi: cfg80211: free beacon_ies when overridden from hidden BSS

This is a more of a cosmetic fix. The branch will only be taken if
proberesp_ies is set, which implies that beacon_ies is not set unless we
are connected to an AP that just did a channel switch. And, in that case
we should have found the BSS in the internal storage to begin with.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20231220133549.b898e22dadff.Id8c4c10aedd176ef2e18a4cad747b299f150f9df@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/scan.c

@@ -1871,8 +1871,12 @@ __cfg80211_bss_update(struct cfg80211_registered_device *rdev,
 				list_add(&new->hidden_list,
 					 &hidden->hidden_list);
 				hidden->refcount++;
+
+				ies = (void *)rcu_dereference(new->pub.beacon_ies);
 				rcu_assign_pointer(new->pub.beacon_ies,
 						   hidden->pub.beacon_ies);
+				if (ies)
+					kfree_rcu(ies, rcu_head);
 			}
 		} else {
 			/*