ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 139 insertions, 0 deletions

diff --git a/net/mac80211/drop.h b/net/mac80211/drop.h
new file mode 100644
index 000000000..f06a8aa90
--- /dev/null
+++ b/net/mac80211/drop.h
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * mac80211 drop reason list
+ *
+ * Copyright (C) 2023-2024, 2026 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_UNUSABLE(R)	\
+	/* 0x00 == ___RX_DROP_UNUSABLE */	\
+	R(RX_DROP_U_MIC_FAIL)			\
+	R(RX_DROP_U_REPLAY)			\
+	R(RX_DROP_U_BAD_MMIE)			\
+	R(RX_DROP_U_DUP)			\
+	R(RX_DROP_U_SPURIOUS)			\
+	R(RX_DROP_U_DECRYPT_FAIL)		\
+	R(RX_DROP_U_NO_KEY_ID)			\
+	R(RX_DROP_U_BAD_CIPHER)			\
+	R(RX_DROP_U_OOM)			\
+	R(RX_DROP_U_NONSEQ_PN)			\
+	R(RX_DROP_U_BAD_KEY_COLOR)		\
+	R(RX_DROP_U_BAD_4ADDR)			\
+	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)		\
+	R(RX_DROP_U_WEP_DEC_FAIL)		\
+	R(RX_DROP_U_NO_IV)			\
+	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)			\
+	R(RX_DROP_U_SHORT_CCMP)			\
+	R(RX_DROP_U_SHORT_CCMP_MIC)		\
+	R(RX_DROP_U_SHORT_GCMP)			\
+	R(RX_DROP_U_SHORT_GCMP_MIC)		\
+	R(RX_DROP_U_SHORT_CMAC)			\
+	R(RX_DROP_U_SHORT_CMAC256)		\
+	R(RX_DROP_U_SHORT_GMAC)			\
+	R(RX_DROP_U_UNEXPECTED_VLAN_4ADDR)	\
+	R(RX_DROP_U_UNEXPECTED_STA_4ADDR)	\
+	R(RX_DROP_U_UNEXPECTED_VLAN_MCAST)	\
+	R(RX_DROP_U_NOT_PORT_CONTROL)		\
+	R(RX_DROP_U_UNEXPECTED_4ADDR_FRAME)	\
+	R(RX_DROP_U_BAD_BCN_KEYIDX)		\
+	/* 0x30 */				\
+	R(RX_DROP_U_BAD_MGMT_KEYIDX)		\
+	R(RX_DROP_U_UNKNOWN_ACTION_REJECTED)	\
+	R(RX_DROP_U_MESH_DS_BITS)		\
+	R(RX_DROP_U_MESH_A3_MISMATCH)		\
+	R(RX_DROP_U_MESH_NO_A4)			\
+	R(RX_DROP_U_MESH_A4_MISMATCH)		\
+	R(RX_DROP_U_MESH_UNEXP_DATA)		\
+	R(RX_DROP_U_MESH_WRONG_ACTION)		\
+	R(RX_DROP_U_MESH_UNEXP_MGMT)		\
+	R(RX_DROP_U_SPURIOUS_NOTIF)		\
+	R(RX_DROP_U_RUNT_DATA)			\
+	R(RX_DROP_U_KEY_TAINTED)		\
+	R(RX_DROP_U_UNPROTECTED)		\
+	R(RX_DROP_U_MCAST_FRAGMENT)		\
+	R(RX_DROP_U_DEFRAG_MISMATCH)		\
+	R(RX_DROP_U_RUNT_MESH_DATA)		\
+	/* 0x40 */				\
+	R(RX_DROP_U_MESH_NO_TTL)		\
+	R(RX_DROP_U_MESH_RMC)			\
+	R(RX_DROP_U_MESH_BAD_AE)		\
+	R(RX_DROP_U_MESH_TTL_EXPIRED)		\
+	R(RX_DROP_U_MESH_NOT_FORWARDING)	\
+	R(RX_DROP_U_AMSDU_WITHOUT_DATA)		\
+	R(RX_DROP_U_NULL_DATA)			\
+	R(RX_DROP_U_UNEXPECTED_4ADDR)		\
+	R(RX_DROP_U_PORT_CONTROL)		\
+	R(RX_DROP_U_UNKNOWN_STA)		\
+	R(RX_DROP_U_RUNT_BAR)			\
+	R(RX_DROP_U_BAR_OUTSIDE_SESSION)	\
+	R(RX_DROP_U_CTRL_FRAME)			\
+	R(RX_DROP_U_RUNT_MGMT)			\
+	R(RX_DROP_U_EXPECTED_MGMT)		\
+	R(RX_DROP_U_NONBCAST_BEACON)		\
+	/* 0x50 */				\
+	R(RX_DROP_U_MALFORMED_ACTION)		\
+	R(RX_DROP_U_UNKNOWN_MCAST_ACTION)	\
+	R(RX_DROP_U_UNEXPECTED_EXT_FRAME)	\
+	R(RX_DROP_U_UNHANDLED_MGMT)		\
+	R(RX_DROP_U_MCAST_DEAUTH)		\
+	R(RX_DROP_U_UNHANDLED_DEAUTH)		\
+	R(RX_DROP_U_MCAST_DISASSOC)		\
+	R(RX_DROP_U_UNHANDLED_DISASSOC)		\
+	R(RX_DROP_U_UNHANDLED_PREQ)		\
+	R(RX_DROP_U_UNHANDLED_MGMT_STYPE)	\
+	R(RX_DROP_U_NO_LINK)			\
+/* 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_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,
+#define DEF(x) x = (__force ieee80211_rx_result)___ ## x,
+	MAC80211_DROP_REASONS_UNUSABLE(DEF)
+#undef DEF
+};
+
+#define RX_RES_IS_UNUSABLE(result)	\
+	(((__force u32)(result) & SKB_DROP_REASON_SUBSYS_MASK) == ___RX_DROP_UNUSABLE)
+
+#endif /* MAC80211_DROP_H */