mac80211: add missing sanity checks for action frames

PATCH New Felix Fietkau 1 participant 1 message Jan 7, 2010 mac80211

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Felix Fietkau

author

2010-01-07 19:24 UTC #0 lore raw

PATCH 1/1 mac80211: add missing sanity checks for action frames

Various missing sanity checks caused rejected action frames to be interpreted as channel switch announcements, which can cause a client mode interface to switch away from its operating channel, thereby losing connectivity. This patch ensures that only spectrum management action frames are processed by the CSA handling function and prevents rejected action frames from getting processed by the MLME code.

Signed-off-by Felix Fietkau <[email protected]>

Cc [email protected]

---

net/mac80211/mlme.c +3 -1

@@ -1451,7 +1451,9 @@ static void ieee80211_sta_rx_queued_mgmt
 			rma = ieee80211_rx_mgmt_disassoc(sdata, mgmt, skb->len);
 			break;
 		case IEEE80211_STYPE_ACTION:
-			/* XXX: differentiate, can only happen for CSA now! */
+			if (mgmt->u.action.category != WLAN_CATEGORY_SPECTRUM_MGMT)
+				break;
+
 			ieee80211_sta_process_chanswitch(sdata,
 					&mgmt->u.action.u.chan_switch.sw_elem,
 					(void *)ifmgd->associated->priv);

net/mac80211/rx.c +4 -0

@@ -1934,6 +1934,10 @@ ieee80211_rx_h_action(struct ieee80211_r
 		}
 		break;
 	default:
+		/* do not process rejected action frames */
+		if (mgmt->u.action.category & 0x80)
+			return RX_DROP_MONITOR;
+
 		return RX_CONTINUE;
 	}