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, 128 insertions, 0 deletions

diff --git a/drivers/net/wireguard/messages.h b/drivers/net/wireguard/messages.h
new file mode 100644
index 000000000..208da7267
--- /dev/null
+++ b/drivers/net/wireguard/messages.h
@@ -0,0 +1,128 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ */
+
+#ifndef _WG_MESSAGES_H
+#define _WG_MESSAGES_H
+
+#include <crypto/curve25519.h>
+#include <crypto/chacha20poly1305.h>
+#include <crypto/blake2s.h>
+
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/skbuff.h>
+
+enum noise_lengths {
+	NOISE_PUBLIC_KEY_LEN = CURVE25519_KEY_SIZE,
+	NOISE_SYMMETRIC_KEY_LEN = CHACHA20POLY1305_KEY_SIZE,
+	NOISE_TIMESTAMP_LEN = sizeof(u64) + sizeof(u32),
+	NOISE_AUTHTAG_LEN = CHACHA20POLY1305_AUTHTAG_SIZE,
+	NOISE_HASH_LEN = BLAKE2S_HASH_SIZE
+};
+
+#define noise_encrypted_len(plain_len) ((plain_len) + NOISE_AUTHTAG_LEN)
+
+enum cookie_values {
+	COOKIE_SECRET_MAX_AGE = 2 * 60,
+	COOKIE_SECRET_LATENCY = 5,
+	COOKIE_NONCE_LEN = XCHACHA20POLY1305_NONCE_SIZE,
+	COOKIE_LEN = 16
+};
+
+enum counter_values {
+	COUNTER_BITS_TOTAL = 8192,
+	COUNTER_REDUNDANT_BITS = BITS_PER_LONG,
+	COUNTER_WINDOW_SIZE = COUNTER_BITS_TOTAL - COUNTER_REDUNDANT_BITS
+};
+
+enum limits {
+	REKEY_AFTER_MESSAGES = 1ULL << 60,
+	REJECT_AFTER_MESSAGES = U64_MAX - COUNTER_WINDOW_SIZE - 1,
+	REKEY_TIMEOUT = 5,
+	REKEY_TIMEOUT_JITTER_MAX_JIFFIES = HZ / 3,
+	REKEY_AFTER_TIME = 120,
+	REJECT_AFTER_TIME = 180,
+	INITIATIONS_PER_SECOND = 50,
+	MAX_PEERS_PER_DEVICE = 1U << 20,
+	KEEPALIVE_TIMEOUT = 10,
+	MAX_TIMER_HANDSHAKES = 90 / REKEY_TIMEOUT,
+	MAX_QUEUED_INCOMING_HANDSHAKES = 4096, /* TODO: replace this with DQL */
+	MAX_STAGED_PACKETS = 128,
+	MAX_QUEUED_PACKETS = 1024 /* TODO: replace this with DQL */
+};
+
+enum message_type {
+	MESSAGE_INVALID = 0,
+	MESSAGE_HANDSHAKE_INITIATION = 1,
+	MESSAGE_HANDSHAKE_RESPONSE = 2,
+	MESSAGE_HANDSHAKE_COOKIE = 3,
+	MESSAGE_DATA = 4
+};
+
+struct message_header {
+	/* The actual layout of this that we want is:
+	 * u8 type
+	 * u8 reserved_zero[3]
+	 *
+	 * But it turns out that by encoding this as little endian,
+	 * we achieve the same thing, and it makes checking faster.
+	 */
+	__le32 type;
+};
+
+struct message_macs {
+	u8 mac1[COOKIE_LEN];
+	u8 mac2[COOKIE_LEN];
+};
+
+struct message_handshake_initiation {
+	struct message_header header;
+	__le32 sender_index;
+	u8 unencrypted_ephemeral[NOISE_PUBLIC_KEY_LEN];
+	u8 encrypted_static[noise_encrypted_len(NOISE_PUBLIC_KEY_LEN)];
+	u8 encrypted_timestamp[noise_encrypted_len(NOISE_TIMESTAMP_LEN)];
+	struct message_macs macs;
+};
+
+struct message_handshake_response {
+	struct message_header header;
+	__le32 sender_index;
+	__le32 receiver_index;
+	u8 unencrypted_ephemeral[NOISE_PUBLIC_KEY_LEN];
+	u8 encrypted_nothing[noise_encrypted_len(0)];
+	struct message_macs macs;
+};
+
+struct message_handshake_cookie {
+	struct message_header header;
+	__le32 receiver_index;
+	u8 nonce[COOKIE_NONCE_LEN];
+	u8 encrypted_cookie[noise_encrypted_len(COOKIE_LEN)];
+};
+
+struct message_data {
+	struct message_header header;
+	__le32 key_idx;
+	__le64 counter;
+	u8 encrypted_data[];
+};
+
+#define message_data_len(plain_len) \
+	(noise_encrypted_len(plain_len) + sizeof(struct message_data))
+
+enum message_alignments {
+	MESSAGE_PADDING_MULTIPLE = 16,
+	MESSAGE_MINIMUM_LENGTH = message_data_len(0)
+};
+
+#define SKB_HEADER_LEN                                       \
+	(max(sizeof(struct iphdr), sizeof(struct ipv6hdr)) + \
+	 sizeof(struct udphdr) + NET_SKB_PAD)
+#define DATA_PACKET_HEAD_ROOM \
+	ALIGN(sizeof(struct message_data) + SKB_HEADER_LEN, 4)
+
+enum { HANDSHAKE_DSCP = 0x88 /* AF41, plus 00 ECN */ };
+
+#endif /* _WG_MESSAGES_H */