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, 30 insertions, 0 deletions

diff --git a/net/mac80211/wep.h b/net/mac80211/wep.h
new file mode 100644
index 000000000..4ffe83554
--- /dev/null
+++ b/net/mac80211/wep.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Software WEP encryption implementation
+ * Copyright 2002, Jouni Malinen <jkmaline@cc.hut.fi>
+ * Copyright 2003, Instant802 Networks, Inc.
+ */
+
+#ifndef WEP_H
+#define WEP_H
+
+#include <linux/skbuff.h>
+#include <linux/types.h>
+#include "ieee80211_i.h"
+#include "key.h"
+
+void ieee80211_wep_init(struct ieee80211_local *local);
+int ieee80211_wep_encrypt_data(struct arc4_ctx *ctx, u8 *rc4key,
+				size_t klen, u8 *data, size_t data_len);
+int ieee80211_wep_encrypt(struct ieee80211_local *local,
+			  struct sk_buff *skb,
+			  const u8 *key, int keylen, int keyidx);
+int ieee80211_wep_decrypt_data(struct arc4_ctx *ctx, u8 *rc4key,
+			       size_t klen, u8 *data, size_t data_len);
+
+ieee80211_rx_result
+ieee80211_crypto_wep_decrypt(struct ieee80211_rx_data *rx);
+ieee80211_tx_result
+ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx);
+
+#endif /* WEP_H */