Merge branch 'net-extend-drop-reasons'

Johannes Berg says:

====================
net: extend drop reasons

Here's v4 of the extended drop reasons, with fixes to kernel-doc
and checkpatch.
====================

Link: https://lore.kernel.org/r/20230419125254.20789-1-johannes@sipsolutions.netSigned-off-by: Jakub Kicinski <kuba@kernel.org>

include/linux/netdevice.h

@@ -52,7 +52,7 @@
 #include <linux/rbtree.h>
 #include <net/net_trackers.h>
 #include <net/net_debug.h>
-#include <net/dropreason.h>
+#include <net/dropreason-core.h>
 
 struct netpoll_info;
 struct device;

include/linux/skbuff.h

@@ -37,7 +37,7 @@
 #include <linux/netfilter/nf_conntrack_common.h>
 #endif
 #include <net/net_debug.h>
-#include <net/dropreason.h>
+#include <net/dropreason-core.h>
 
 /**
  * DOC: skb checksums

include/net/inet_frag.h

@@ -7,7 +7,7 @@
 #include <linux/in6.h>
 #include <linux/rbtree_types.h>
 #include <linux/refcount.h>
-#include <net/dropreason.h>
+#include <net/dropreason-core.h>
 
 /* Per netns frag queues directory */
 struct fqdir {

net/core/drop_monitor.c

@@ -21,6 +21,7 @@
 #include <linux/workqueue.h>
 #include <linux/netlink.h>
 #include <linux/net_dropmon.h>
+#include <linux/bitfield.h>
 #include <linux/percpu.h>
 #include <linux/timer.h>
 #include <linux/bitops.h>
@@ -29,6 +30,7 @@
 #include <net/genetlink.h>
 #include <net/netevent.h>
 #include <net/flow_offload.h>
+#include <net/dropreason.h>
 #include <net/devlink.h>
 
 #include <trace/events/skb.h>
@@ -504,8 +506,6 @@ static void net_dm_packet_trace_kfree_skb_hit(void *ignore,
 	if (!nskb)
 		return;
 
-	if (unlikely(reason >= SKB_DROP_REASON_MAX || reason <= 0))
-		reason = SKB_DROP_REASON_NOT_SPECIFIED;
 	cb = NET_DM_SKB_CB(nskb);
 	cb->reason = reason;
 	cb->pc = location;
@@ -552,9 +552,9 @@ static size_t net_dm_in_port_size(void)
 }
 
 #define NET_DM_MAX_SYMBOL_LEN 40
+#define NET_DM_MAX_REASON_LEN 50
 
-static size_t net_dm_packet_report_size(size_t payload_len,
-					enum skb_drop_reason reason)
+static size_t net_dm_packet_report_size(size_t payload_len)
 {
 	size_t size;
 
@@ -576,7 +576,7 @@ static size_t net_dm_packet_report_size(size_t payload_len,
 	       /* NET_DM_ATTR_PROTO */
 	       nla_total_size(sizeof(u16)) +
 	       /* NET_DM_ATTR_REASON */
-	       nla_total_size(strlen(drop_reasons[reason]) + 1) +
+	       nla_total_size(NET_DM_MAX_REASON_LEN + 1) +
 	       /* NET_DM_ATTR_PAYLOAD */
 	       nla_total_size(payload_len);
 }
@@ -610,6 +610,8 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb,
 				     size_t payload_len)
 {
 	struct net_dm_skb_cb *cb = NET_DM_SKB_CB(skb);
+	const struct drop_reason_list *list = NULL;
+	unsigned int subsys, subsys_reason;
 	char buf[NET_DM_MAX_SYMBOL_LEN];
 	struct nlattr *attr;
 	void *hdr;
@@ -627,9 +629,24 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb,
 			      NET_DM_ATTR_PAD))
 		goto nla_put_failure;
 
+	rcu_read_lock();
+	subsys = u32_get_bits(cb->reason, SKB_DROP_REASON_SUBSYS_MASK);
+	if (subsys < SKB_DROP_REASON_SUBSYS_NUM)
+		list = rcu_dereference(drop_reasons_by_subsys[subsys]);
+	subsys_reason = cb->reason & ~SKB_DROP_REASON_SUBSYS_MASK;
+	if (!list ||
+	    subsys_reason >= list->n_reasons ||
+	    !list->reasons[subsys_reason] ||
+	    strlen(list->reasons[subsys_reason]) > NET_DM_MAX_REASON_LEN) {
+		list = rcu_dereference(drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_CORE]);
+		subsys_reason = SKB_DROP_REASON_NOT_SPECIFIED;
+	}
 	if (nla_put_string(msg, NET_DM_ATTR_REASON,
-			   drop_reasons[cb->reason]))
+			   list->reasons[subsys_reason])) {
+		rcu_read_unlock();
 		goto nla_put_failure;
+	}
+	rcu_read_unlock();
 
 	snprintf(buf, sizeof(buf), "%pS", cb->pc);
 	if (nla_put_string(msg, NET_DM_ATTR_SYMBOL, buf))
@@ -687,9 +704,7 @@ static void net_dm_packet_report(struct sk_buff *skb)
 	if (net_dm_trunc_len)
 		payload_len = min_t(size_t, net_dm_trunc_len, payload_len);
 
-	msg = nlmsg_new(net_dm_packet_report_size(payload_len,
-						  NET_DM_SKB_CB(skb)->reason),
-			GFP_KERNEL);
+	msg = nlmsg_new(net_dm_packet_report_size(payload_len), GFP_KERNEL);
 	if (!msg)
 		goto out;
 

net/core/skbuff.c

@@ -58,6 +58,7 @@
 #include <linux/scatterlist.h>
 #include <linux/errqueue.h>
 #include <linux/prefetch.h>
+#include <linux/bitfield.h>
 #include <linux/if_vlan.h>
 #include <linux/mpls.h>
 #include <linux/kcov.h>
@@ -72,6 +73,7 @@
 #include <net/mptcp.h>
 #include <net/mctp.h>
 #include <net/page_pool.h>
+#include <net/dropreason.h>
 
 #include <linux/uaccess.h>
 #include <trace/events/skb.h>
@@ -122,11 +124,59 @@ EXPORT_SYMBOL(sysctl_max_skb_frags);
 
 #undef FN
 #define FN(reason) [SKB_DROP_REASON_##reason] = #reason,
-const char * const drop_reasons[] = {
+static const char * const drop_reasons[] = {
 	[SKB_CONSUMED] = "CONSUMED",
 	DEFINE_DROP_REASON(FN, FN)
 };
-EXPORT_SYMBOL(drop_reasons);
+
+static const struct drop_reason_list drop_reasons_core = {
+	.reasons = drop_reasons,
+	.n_reasons = ARRAY_SIZE(drop_reasons),
+};
+
+const struct drop_reason_list __rcu *
+drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_NUM] = {
+	[SKB_DROP_REASON_SUBSYS_CORE] = RCU_INITIALIZER(&drop_reasons_core),
+};
+EXPORT_SYMBOL(drop_reasons_by_subsys);
+
+/**
+ * drop_reasons_register_subsys - register another drop reason subsystem
+ * @subsys: the subsystem to register, must not be the core
+ * @list: the list of drop reasons within the subsystem, must point to
+ *	a statically initialized list
+ */
+void drop_reasons_register_subsys(enum skb_drop_reason_subsys subsys,
+				  const struct drop_reason_list *list)
+{
+	if (WARN(subsys <= SKB_DROP_REASON_SUBSYS_CORE ||
+		 subsys >= ARRAY_SIZE(drop_reasons_by_subsys),
+		 "invalid subsystem %d\n", subsys))
+		return;
+
+	/* must point to statically allocated memory, so INIT is OK */
+	RCU_INIT_POINTER(drop_reasons_by_subsys[subsys], list);
+}
+EXPORT_SYMBOL_GPL(drop_reasons_register_subsys);
+
+/**
+ * drop_reasons_unregister_subsys - unregister a drop reason subsystem
+ * @subsys: the subsystem to remove, must not be the core
+ *
+ * Note: This will synchronize_rcu() to ensure no users when it returns.
+ */
+void drop_reasons_unregister_subsys(enum skb_drop_reason_subsys subsys)
+{
+	if (WARN(subsys <= SKB_DROP_REASON_SUBSYS_CORE ||
+		 subsys >= ARRAY_SIZE(drop_reasons_by_subsys),
+		 "invalid subsystem %d\n", subsys))
+		return;
+
+	RCU_INIT_POINTER(drop_reasons_by_subsys[subsys], NULL);
+
+	synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(drop_reasons_unregister_subsys);
 
 /**
  *	skb_panic - private function for out-of-line support
@@ -986,7 +1036,10 @@ bool __kfree_skb_reason(struct sk_buff *skb, enum skb_drop_reason reason)
 	if (unlikely(!skb_unref(skb)))
 		return false;
 
-	DEBUG_NET_WARN_ON_ONCE(reason <= 0 || reason >= SKB_DROP_REASON_MAX);
+	DEBUG_NET_WARN_ON_ONCE(reason == SKB_NOT_DROPPED_YET ||
+			       u32_get_bits(reason,
+					    SKB_DROP_REASON_SUBSYS_MASK) >=
+				SKB_DROP_REASON_SUBSYS_NUM);
 
 	if (reason == SKB_CONSUMED)
 		trace_consume_skb(skb, __builtin_return_address(0));

net/mac80211/drop.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * mac80211 drop reason list
+ *
+ * Copyright (C) 2023 Intel Corporation
+ */
+
+#ifndef MAC80211_DROP_H
+#define MAC80211_DROP_H
+#include <net/dropreason.h>
+
+typedef unsigned int __bitwise ieee80211_rx_result;
+
+#define MAC80211_DROP_REASONS_MONITOR(R)	\
+	R(RX_DROP_M_UNEXPECTED_4ADDR_FRAME)	\
+	R(RX_DROP_M_BAD_BCN_KEYIDX)		\
+	R(RX_DROP_M_BAD_MGMT_KEYIDX)		\
+/* this line for the trailing \ - add before this */
+
+#define MAC80211_DROP_REASONS_UNUSABLE(R)	\
+	R(RX_DROP_U_MIC_FAIL)			\
+	R(RX_DROP_U_REPLAY)			\
+	R(RX_DROP_U_BAD_MMIE)			\
+/* this line for the trailing \ - add before this */
+
+/* having two enums allows for checking ieee80211_rx_result use with sparse */
+enum ___mac80211_drop_reason {
+/* if we get to the end of handlers with RX_CONTINUE this will be the reason */
+	___RX_CONTINUE	= SKB_CONSUMED,
+
+/* this never gets used as an argument to kfree_skb_reason() */
+	___RX_QUEUED	= SKB_NOT_DROPPED_YET,
+
+#define ENUM(x) ___ ## x,
+	___RX_DROP_MONITOR = SKB_DROP_REASON_SUBSYS_MAC80211_MONITOR <<
+		SKB_DROP_REASON_SUBSYS_SHIFT,
+	MAC80211_DROP_REASONS_MONITOR(ENUM)
+
+	___RX_DROP_UNUSABLE = SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE <<
+		SKB_DROP_REASON_SUBSYS_SHIFT,
+	MAC80211_DROP_REASONS_UNUSABLE(ENUM)
+#undef ENUM
+};
+
+enum mac80211_drop_reason {
+	RX_CONTINUE	 = (__force ieee80211_rx_result)___RX_CONTINUE,
+	RX_QUEUED	 = (__force ieee80211_rx_result)___RX_QUEUED,
+	RX_DROP_MONITOR	 = (__force ieee80211_rx_result)___RX_DROP_MONITOR,
+	RX_DROP_UNUSABLE = (__force ieee80211_rx_result)___RX_DROP_UNUSABLE,
+#define DEF(x) x = (__force ieee80211_rx_result)___ ## x,
+	MAC80211_DROP_REASONS_MONITOR(DEF)
+	MAC80211_DROP_REASONS_UNUSABLE(DEF)
+#undef DEF
+};
+
+#endif /* MAC80211_DROP_H */

net/mac80211/ieee80211_i.h

@@ -33,6 +33,7 @@
 #include "key.h"
 #include "sta_info.h"
 #include "debug.h"
+#include "drop.h"
 
 extern const struct cfg80211_ops mac80211_config_ops;
 
@@ -170,13 +171,6 @@ struct ieee80211_tx_data {
 	unsigned int flags;
 };
 
-
-typedef unsigned __bitwise ieee80211_rx_result;
-#define RX_CONTINUE		((__force ieee80211_rx_result) 0u)
-#define RX_DROP_UNUSABLE	((__force ieee80211_rx_result) 1u)
-#define RX_DROP_MONITOR		((__force ieee80211_rx_result) 2u)
-#define RX_QUEUED		((__force ieee80211_rx_result) 3u)
-
 /**
  * enum ieee80211_packet_rx_flags - packet RX flags
  * @IEEE80211_RX_AMSDU: a-MSDU packet

net/mac80211/main.c

@@ -22,6 +22,7 @@
 #include <linux/bitmap.h>
 #include <linux/inetdevice.h>
 #include <net/net_namespace.h>
+#include <net/dropreason.h>
 #include <net/cfg80211.h>
 #include <net/addrconf.h>
 
@@ -1542,6 +1543,28 @@ void ieee80211_free_hw(struct ieee80211_hw *hw)
 }
 EXPORT_SYMBOL(ieee80211_free_hw);
 
+static const char * const drop_reasons_monitor[] = {
+#define V(x)	#x,
+	[0] = "RX_DROP_MONITOR",
+	MAC80211_DROP_REASONS_MONITOR(V)
+};
+
+static struct drop_reason_list drop_reason_list_monitor = {
+	.reasons = drop_reasons_monitor,
+	.n_reasons = ARRAY_SIZE(drop_reasons_monitor),
+};
+
+static const char * const drop_reasons_unusable[] = {
+	[0] = "RX_DROP_UNUSABLE",
+	MAC80211_DROP_REASONS_UNUSABLE(V)
+#undef V
+};
+
+static struct drop_reason_list drop_reason_list_unusable = {
+	.reasons = drop_reasons_unusable,
+	.n_reasons = ARRAY_SIZE(drop_reasons_unusable),
+};
+
 static int __init ieee80211_init(void)
 {
 	struct sk_buff *skb;
@@ -1559,6 +1582,11 @@ static int __init ieee80211_init(void)
 	if (ret)
 		goto err_netdev;
 
+	drop_reasons_register_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_MONITOR,
+				     &drop_reason_list_monitor);
+	drop_reasons_register_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE,
+				     &drop_reason_list_unusable);
+
 	return 0;
  err_netdev:
 	rc80211_minstrel_exit();
@@ -1574,6 +1602,9 @@ static void __exit ieee80211_exit(void)
 
 	ieee80211_iface_exit();
 
+	drop_reasons_unregister_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_MONITOR);
+	drop_reasons_unregister_subsys(SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE);
+
 	rcu_barrier();
 }
 

net/mac80211/rx.c

@@ -1826,7 +1826,7 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 				cfg80211_rx_unexpected_4addr_frame(
 					rx->sdata->dev, sta->sta.addr,
 					GFP_ATOMIC);
-			return RX_DROP_MONITOR;
+			return RX_DROP_M_UNEXPECTED_4ADDR_FRAME;
 		}
 		/*
 		 * Update counter and free packet here to avoid
@@ -1961,7 +1961,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
 							     skb->data,
 							     skb->len);
-			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
+			return RX_DROP_M_BAD_BCN_KEYIDX;
 		}
 
 		rx->key = ieee80211_rx_get_bigtk(rx, mmie_keyidx);
@@ -1975,7 +1975,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 
 		if (mmie_keyidx < NUM_DEFAULT_KEYS ||
 		    mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS)
-			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
+			return RX_DROP_M_BAD_MGMT_KEYIDX; /* unexpected BIP keyidx */
 		if (rx->link_sta) {
 			if (ieee80211_is_group_privacy_action(skb) &&
 			    test_sta_flag(rx->sta, WLAN_STA_MFP))
@@ -3960,7 +3960,8 @@ ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
 }
 
 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
-					struct ieee80211_rate *rate)
+					struct ieee80211_rate *rate,
+					ieee80211_rx_result reason)
 {
 	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_local *local = rx->local;
@@ -4024,42 +4025,38 @@ static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
 	}
 
  out_free_skb:
-	dev_kfree_skb(skb);
+	kfree_skb_reason(skb, (__force u32)reason);
 }
 
 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
 					 ieee80211_rx_result res)
 {
-	switch (res) {
-	case RX_DROP_MONITOR:
-		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
-		if (rx->sta)
-			rx->link_sta->rx_stats.dropped++;
-		fallthrough;
-	case RX_CONTINUE: {
-		struct ieee80211_rate *rate = NULL;
-		struct ieee80211_supported_band *sband;
-		struct ieee80211_rx_status *status;
-
-		status = IEEE80211_SKB_RXCB((rx->skb));
+	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_rate *rate = NULL;
 
-		sband = rx->local->hw.wiphy->bands[status->band];
-		if (status->encoding == RX_ENC_LEGACY)
-			rate = &sband->bitrates[status->rate_idx];
+	if (res == RX_QUEUED) {
+		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
+		return;
+	}
 
-		ieee80211_rx_cooked_monitor(rx, rate);
-		break;
-		}
-	case RX_DROP_UNUSABLE:
+	if (res != RX_CONTINUE) {
 		I802_DEBUG_INC(rx->sdata->local->rx_handlers_drop);
 		if (rx->sta)
 			rx->link_sta->rx_stats.dropped++;
-		dev_kfree_skb(rx->skb);
-		break;
-	case RX_QUEUED:
-		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
-		break;
 	}
+
+	if (u32_get_bits((__force u32)res, SKB_DROP_REASON_SUBSYS_MASK) ==
+			SKB_DROP_REASON_SUBSYS_MAC80211_UNUSABLE) {
+		kfree_skb_reason(rx->skb, (__force u32)res);
+		return;
+	}
+
+	sband = rx->local->hw.wiphy->bands[status->band];
+	if (status->encoding == RX_ENC_LEGACY)
+		rate = &sband->bitrates[status->rate_idx];
+
+	ieee80211_rx_cooked_monitor(rx, rate, res);
 }
 
 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,

net/mac80211/wpa.c

@@ -550,7 +550,7 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 		if (res < 0 ||
 		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 			key->u.ccmp.replays++;
-			return RX_DROP_UNUSABLE;
+			return RX_DROP_U_REPLAY;
 		}
 
 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
@@ -564,7 +564,7 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
 				    skb->data + hdrlen + IEEE80211_CCMP_HDR_LEN,
 				    data_len,
 				    skb->data + skb->len - mic_len))
-				return RX_DROP_UNUSABLE;
+				return RX_DROP_U_MIC_FAIL;
 		}
 
 		memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
@@ -746,7 +746,7 @@ ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 		if (res < 0 ||
 		    (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) {
 			key->u.gcmp.replays++;
-			return RX_DROP_UNUSABLE;
+			return RX_DROP_U_REPLAY;
 		}
 
 		if (!(status->flag & RX_FLAG_DECRYPTED)) {
@@ -761,7 +761,7 @@ ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
 				    data_len,
 				    skb->data + skb->len -
 				    IEEE80211_GCMP_MIC_LEN))
-				return RX_DROP_UNUSABLE;
+				return RX_DROP_U_MIC_FAIL;
 		}
 
 		memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
@@ -930,13 +930,13 @@ ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
 		(skb->data + skb->len - sizeof(*mmie));
 	if (mmie->element_id != WLAN_EID_MMIE ||
 	    mmie->length != sizeof(*mmie) - 2)
-		return RX_DROP_UNUSABLE; /* Invalid MMIE */
+		return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
 
 	bip_ipn_swap(ipn, mmie->sequence_number);
 
 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
 		key->u.aes_cmac.replays++;
-		return RX_DROP_UNUSABLE;
+		return RX_DROP_U_REPLAY;
 	}
 
 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
@@ -946,7 +946,7 @@ ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx)
 				   skb->data + 24, skb->len - 24, mic);
 		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 			key->u.aes_cmac.icverrors++;
-			return RX_DROP_UNUSABLE;
+			return RX_DROP_U_MIC_FAIL;
 		}
 	}
 
@@ -986,7 +986,7 @@ ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
 
 	if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) {
 		key->u.aes_cmac.replays++;
-		return RX_DROP_UNUSABLE;
+		return RX_DROP_U_REPLAY;
 	}
 
 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
@@ -996,7 +996,7 @@ ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx)
 				       skb->data + 24, skb->len - 24, mic);
 		if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 			key->u.aes_cmac.icverrors++;
-			return RX_DROP_UNUSABLE;
+			return RX_DROP_U_MIC_FAIL;
 		}
 	}
 
@@ -1079,13 +1079,13 @@ ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
 		(skb->data + skb->len - sizeof(*mmie));
 	if (mmie->element_id != WLAN_EID_MMIE ||
 	    mmie->length != sizeof(*mmie) - 2)
-		return RX_DROP_UNUSABLE; /* Invalid MMIE */
+		return RX_DROP_U_BAD_MMIE; /* Invalid MMIE */
 
 	bip_ipn_swap(ipn, mmie->sequence_number);
 
 	if (memcmp(ipn, key->u.aes_gmac.rx_pn, 6) <= 0) {
 		key->u.aes_gmac.replays++;
-		return RX_DROP_UNUSABLE;
+		return RX_DROP_U_REPLAY;
 	}
 
 	if (!(status->flag & RX_FLAG_DECRYPTED)) {
@@ -1104,7 +1104,7 @@ ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx)
 		    crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) {
 			key->u.aes_gmac.icverrors++;
 			kfree(mic);
-			return RX_DROP_UNUSABLE;
+			return RX_DROP_U_MIC_FAIL;
 		}
 		kfree(mic);
 	}