Merge tag 'mac80211-for-net-2021-10-21' of...

Merge tag 'mac80211-for-net-2021-10-21' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Two small fixes:
 * RCU misuse in scan processing in cfg80211
 * missing size check for HE data in mac80211 mesh

* tag 'mac80211-for-net-2021-10-21' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211:
  cfg80211: scan: fix RCU in cfg80211_add_nontrans_list()
  mac80211: mesh: fix HE operation element length check
====================

Link: https://lore.kernel.org/r/20211021154351.134297-1-johannes@sipsolutions.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

net/mac80211/mesh.c

@@ -672,7 +672,7 @@ ieee80211_mesh_update_bss_params(struct ieee80211_sub_if_data *sdata,
 				 u8 *ie, u8 ie_len)
 {
 	struct ieee80211_supported_band *sband;
-	const u8 *cap;
+	const struct element *cap;
 	const struct ieee80211_he_operation *he_oper = NULL;
 
 	sband = ieee80211_get_sband(sdata);
@@ -687,9 +687,10 @@ ieee80211_mesh_update_bss_params(struct ieee80211_sub_if_data *sdata,
 
 	sdata->vif.bss_conf.he_support = true;
 
-	cap = cfg80211_find_ext_ie(WLAN_EID_EXT_HE_OPERATION, ie, ie_len);
-	if (cap && cap[1] >= ieee80211_he_oper_size(&cap[3]))
-		he_oper = (void *)(cap + 3);
+	cap = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION, ie, ie_len);
+	if (cap && cap->datalen >= 1 + sizeof(*he_oper) &&
+	    cap->datalen >= 1 + ieee80211_he_oper_size(cap->data + 1))
+		he_oper = (void *)(cap->data + 1);
 
 	if (he_oper)
 		sdata->vif.bss_conf.he_oper.params =

net/wireless/scan.c

@@ -418,14 +418,17 @@ cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss,
 	}
 	ssid_len = ssid[1];
 	ssid = ssid + 2;
-	rcu_read_unlock();
 
 	/* check if nontrans_bss is in the list */
 	list_for_each_entry(bss, &trans_bss->nontrans_list, nontrans_list) {
-		if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len))
+		if (is_bss(bss, nontrans_bss->bssid, ssid, ssid_len)) {
+			rcu_read_unlock();
 			return 0;
+		}
 	}
 
+	rcu_read_unlock();
+
 	/* add to the list */
 	list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list);
 	return 0;