wifi: mac80211: split ieee80211_drop_unencrypted_mgmt() return value

This has many different reasons, split the return value into
the individual reasons for better traceability. Also, since
symbolic tracing doesn't work for these, add a few comments
for the numbering.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/drop.h

@@ -18,6 +18,7 @@ typedef unsigned int __bitwise ieee80211_rx_result;
 /* this line for the trailing \ - add before this */
 
 #define MAC80211_DROP_REASONS_UNUSABLE(R)	\
+	/* 0x00 == ___RX_DROP_UNUSABLE */	\
 	R(RX_DROP_U_MIC_FAIL)			\
 	R(RX_DROP_U_REPLAY)			\
 	R(RX_DROP_U_BAD_MMIE)			\
@@ -33,8 +34,15 @@ typedef unsigned int __bitwise ieee80211_rx_result;
 	R(RX_DROP_U_BAD_AMSDU)			\
 	R(RX_DROP_U_BAD_AMSDU_CIPHER)		\
 	R(RX_DROP_U_INVALID_8023)		\
+	/* 0x10 */				\
 	R(RX_DROP_U_RUNT_ACTION)		\
 	R(RX_DROP_U_UNPROT_ACTION)		\
+	R(RX_DROP_U_UNPROT_DUAL)		\
+	R(RX_DROP_U_UNPROT_UCAST_MGMT)		\
+	R(RX_DROP_U_UNPROT_MCAST_MGMT)		\
+	R(RX_DROP_U_UNPROT_BEACON)		\
+	R(RX_DROP_U_UNPROT_UNICAST_PUB_ACTION)	\
+	R(RX_DROP_U_UNPROT_ROBUST_ACTION)	\
 	R(RX_DROP_U_ACTION_UNKNOWN_SRC)		\
 	R(RX_DROP_U_REJECTED_ACTION_RESPONSE)	\
 	R(RX_DROP_U_EXPECT_DEFRAG_PROT)		\
@@ -43,6 +51,7 @@ typedef unsigned int __bitwise ieee80211_rx_result;
 	R(RX_DROP_U_NO_ICV)			\
 	R(RX_DROP_U_AP_RX_GROUPCAST)		\
 	R(RX_DROP_U_SHORT_MMIC)			\
+	/* 0x20 */				\
 	R(RX_DROP_U_MMIC_FAIL)			\
 	R(RX_DROP_U_SHORT_TKIP)			\
 	R(RX_DROP_U_TKIP_FAIL)			\

net/mac80211/rx.c

@@ -2416,12 +2416,12 @@ static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
 	 * decrypted them already.
 	 */
 	if (status->flag & RX_FLAG_DECRYPTED)
-		return 0;
+		return RX_CONTINUE;
 
 	/* drop unicast protected dual (that wasn't protected) */
 	if (ieee80211_is_action(fc) &&
 	    mgmt->u.action.category == WLAN_CATEGORY_PROTECTED_DUAL_OF_ACTION)
-		return -EACCES;
+		return RX_DROP_U_UNPROT_DUAL;
 
 	if (rx->sta && test_sta_flag(rx->sta, WLAN_STA_MFP)) {
 		if (unlikely(!ieee80211_has_protected(fc) &&
@@ -2433,13 +2433,13 @@ static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
 				 * during 4-way-HS (key is installed after HS).
 				 */
 				if (!rx->key)
-					return 0;
+					return RX_CONTINUE;
 
 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
 							     rx->skb->data,
 							     rx->skb->len);
 			}
-			return -EACCES;
+			return RX_DROP_U_UNPROT_UCAST_MGMT;
 		}
 		/* BIP does not use Protected field, so need to check MMIE */
 		if (unlikely(ieee80211_is_multicast_robust_mgmt_frame(rx->skb) &&
@@ -2449,14 +2449,14 @@ static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
 							     rx->skb->data,
 							     rx->skb->len);
-			return -EACCES;
+			return RX_DROP_U_UNPROT_MCAST_MGMT;
 		}
 		if (unlikely(ieee80211_is_beacon(fc) && rx->key &&
 			     ieee80211_get_mmie_keyidx(rx->skb) < 0)) {
 			cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
 						     rx->skb->data,
 						     rx->skb->len);
-			return -EACCES;
+			return RX_DROP_U_UNPROT_BEACON;
 		}
 		/*
 		 * When using MFP, Action frames are not allowed prior to
@@ -2464,13 +2464,13 @@ static int ieee80211_drop_unencrypted_mgmt(struct ieee80211_rx_data *rx)
 		 */
 		if (unlikely(ieee80211_is_action(fc) && !rx->key &&
 			     ieee80211_is_robust_mgmt_frame(rx->skb)))
-			return -EACCES;
+			return RX_DROP_U_UNPROT_ACTION;
 
 		/* drop unicast public action frames when using MPF */
 		if (is_unicast_ether_addr(mgmt->da) &&
 		    ieee80211_is_public_action((void *)rx->skb->data,
 					       rx->skb->len))
-			return -EACCES;
+			return RX_DROP_U_UNPROT_UNICAST_PUB_ACTION;
 	}
 
 	return 0;
@@ -3400,10 +3400,7 @@ ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
 		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
 	}
 
-	if (ieee80211_drop_unencrypted_mgmt(rx))
-		return RX_DROP_U_UNPROT_ACTION;
-
-	return RX_CONTINUE;
+	return ieee80211_drop_unencrypted_mgmt(rx);
 }
 
 static bool