From e6a3cf0e4fd98f36be9352b92d40cfeb79993fc9 Mon Sep 17 00:00:00 2001
From: Shayne Chen <shayne.chen@mediatek.com>
Date: Mon, 21 Aug 2023 14:20:49 +0800
Subject: [PATCH] Revert mac80211: use the new drop reasons infrastructure

---
 net/mac80211/drop.h        | 56 --------------------------------------
 net/mac80211/ieee80211_i.h |  8 +++++-
 net/mac80211/main.c        | 31 ---------------------
 net/mac80211/rx.c          | 55 +++++++++++++++++++------------------
 net/mac80211/wpa.c         | 24 ++++++++--------
 5 files changed, 48 insertions(+), 126 deletions(-)
 delete mode 100644 net/mac80211/drop.h

diff --git a/net/mac80211/drop.h b/net/mac80211/drop.h
deleted file mode 100644
index 49dc809..0000000
--- a/net/mac80211/drop.h
+++ /dev/null
@@ -1,56 +0,0 @@
-/* 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 */
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 9fdfd11..7ca2482 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -33,7 +33,6 @@
 #include "key.h"
 #include "sta_info.h"
 #include "debug.h"
-#include "drop.h"
 
 extern const struct cfg80211_ops mac80211_config_ops;
 
@@ -171,6 +170,13 @@ 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
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index c2f25a4..e2f7ae5 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -22,7 +22,6 @@
 #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>
 
@@ -1544,28 +1543,6 @@ 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;
@@ -1583,11 +1560,6 @@ 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();
@@ -1603,9 +1575,6 @@ 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();
 }
 
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 491047d..8ffe90d 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1828,7 +1828,7 @@ 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_M_UNEXPECTED_4ADDR_FRAME;
+			return RX_DROP_MONITOR;
 		}
 		/*
 		 * Update counter and free packet here to avoid
@@ -1963,7 +1963,7 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
 				cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev,
 							     skb->data,
 							     skb->len);
-			return RX_DROP_M_BAD_BCN_KEYIDX;
+			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 		}
 
 		rx->key = ieee80211_rx_get_bigtk(rx, mmie_keyidx);
@@ -1977,7 +1977,7 @@ 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_M_BAD_MGMT_KEYIDX; /* unexpected BIP keyidx */
+			return RX_DROP_MONITOR; /* unexpected BIP keyidx */
 		if (rx->link_sta) {
 			if (ieee80211_is_group_privacy_action(skb) &&
 			    test_sta_flag(rx->sta, WLAN_STA_MFP))
@@ -3981,8 +3981,7 @@ ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx)
 }
 
 static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
-					struct ieee80211_rate *rate,
-					ieee80211_rx_result reason)
+					struct ieee80211_rate *rate)
 {
 	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_local *local = rx->local;
@@ -4046,38 +4045,42 @@ static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx,
 	}
 
  out_free_skb:
-	kfree_skb_reason(skb, (__force u32)reason);
+	dev_kfree_skb(skb);
 }
 
 static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
 					 ieee80211_rx_result res)
 {
-	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
-	struct ieee80211_supported_band *sband;
-	struct ieee80211_rate *rate = NULL;
-
-	if (res == RX_QUEUED) {
-		I802_DEBUG_INC(rx->sdata->local->rx_handlers_queued);
-		return;
-	}
-
-	if (res != RX_CONTINUE) {
+	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;
 
-	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;
-	}
+		status = IEEE80211_SKB_RXCB((rx->skb));
 
-	sband = rx->local->hw.wiphy->bands[status->band];
-	if (status->encoding == RX_ENC_LEGACY)
-		rate = &sband->bitrates[status->rate_idx];
+		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);
+		ieee80211_rx_cooked_monitor(rx, rate);
+		break;
+		}
+	case RX_DROP_UNUSABLE:
+		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;
+	}
 }
 
 static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 4133496..20f742b 100644
--- a/net/mac80211/wpa.c
+++ b/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_U_REPLAY;
+			return RX_DROP_UNUSABLE;
 		}
 
 		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_U_MIC_FAIL;
+				return RX_DROP_UNUSABLE;
 		}
 
 		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_U_REPLAY;
+			return RX_DROP_UNUSABLE;
 		}
 
 		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_U_MIC_FAIL;
+				return RX_DROP_UNUSABLE;
 		}
 
 		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_U_BAD_MMIE; /* Invalid MMIE */
+		return RX_DROP_UNUSABLE; /* 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_U_REPLAY;
+		return RX_DROP_UNUSABLE;
 	}
 
 	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_U_MIC_FAIL;
+			return RX_DROP_UNUSABLE;
 		}
 	}
 
@@ -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_U_REPLAY;
+		return RX_DROP_UNUSABLE;
 	}
 
 	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_U_MIC_FAIL;
+			return RX_DROP_UNUSABLE;
 		}
 	}
 
@@ -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_U_BAD_MMIE; /* Invalid MMIE */
+		return RX_DROP_UNUSABLE; /* 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_U_REPLAY;
+		return RX_DROP_UNUSABLE;
 	}
 
 	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_U_MIC_FAIL;
+			return RX_DROP_UNUSABLE;
 		}
 		kfree(mic);
 	}
-- 
2.39.2