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, 49 insertions, 0 deletions

diff --git a/fs/smb/server/glob.h b/fs/smb/server/glob.h
new file mode 100644
index 000000000..4ea187af2
--- /dev/null
+++ b/fs/smb/server/glob.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *   Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org>
+ *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
+ */
+
+#ifndef __KSMBD_GLOB_H
+#define __KSMBD_GLOB_H
+
+#include <linux/ctype.h>
+
+#include "unicode.h"
+#include "vfs_cache.h"
+
+extern int ksmbd_debug_types;
+
+#define KSMBD_DEBUG_SMB		BIT(0)
+#define KSMBD_DEBUG_AUTH	BIT(1)
+#define KSMBD_DEBUG_VFS		BIT(2)
+#define KSMBD_DEBUG_OPLOCK      BIT(3)
+#define KSMBD_DEBUG_IPC         BIT(4)
+#define KSMBD_DEBUG_CONN        BIT(5)
+#define KSMBD_DEBUG_RDMA        BIT(6)
+#define KSMBD_DEBUG_ALL         (KSMBD_DEBUG_SMB | KSMBD_DEBUG_AUTH |	\
+				KSMBD_DEBUG_VFS | KSMBD_DEBUG_OPLOCK |	\
+				KSMBD_DEBUG_IPC | KSMBD_DEBUG_CONN |	\
+				KSMBD_DEBUG_RDMA)
+
+#ifdef pr_fmt
+#undef pr_fmt
+#endif
+
+#ifdef SUBMOD_NAME
+#define pr_fmt(fmt)	"ksmbd: " SUBMOD_NAME ": " fmt
+#else
+#define pr_fmt(fmt)	"ksmbd: " fmt
+#endif
+
+#define ksmbd_debug(type, fmt, ...)				\
+	do {							\
+		if (ksmbd_debug_types & KSMBD_DEBUG_##type)	\
+			pr_info(fmt, ##__VA_ARGS__);		\
+	} while (0)
+
+#define UNICODE_LEN(x)		((x) * 2)
+
+#define KSMBD_DEFAULT_GFP	(GFP_KERNEL | __GFP_RETRY_MAYFAIL)
+
+#endif /* __KSMBD_GLOB_H */