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, 173 insertions, 0 deletions

diff --git a/drivers/usb/serial/usb-serial-simple.c b/drivers/usb/serial/usb-serial-simple.c
new file mode 100644
index 000000000..a0afaf254
--- /dev/null
+++ b/drivers/usb/serial/usb-serial-simple.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB Serial "Simple" driver
+ *
+ * Copyright (C) 2001-2006,2008,2013 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 2005 Arthur Huillet (ahuillet@users.sf.net)
+ * Copyright (C) 2005 Thomas Hergenhahn <thomas.hergenhahn@suse.de>
+ * Copyright (C) 2009 Outpost Embedded, LLC
+ * Copyright (C) 2010 Zilogic Systems <code@zilogic.com>
+ * Copyright (C) 2013 Wei Shuai <cpuwolf@gmail.com>
+ * Copyright (C) 2013 Linux Foundation
+ */
+
+#include <linux/kernel.h>
+#include <linux/tty.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+
+#define DEVICE_N(vendor, IDS, nport)				\
+static const struct usb_device_id vendor##_id_table[] = {	\
+	IDS(),							\
+	{ },							\
+};								\
+static struct usb_serial_driver vendor##_device = {		\
+	.driver = {						\
+		.name =		#vendor,			\
+	},							\
+	.id_table =		vendor##_id_table,		\
+	.num_ports =		nport,				\
+};
+
+#define DEVICE(vendor, IDS)	DEVICE_N(vendor, IDS, 1)
+
+/* Medtronic CareLink USB driver */
+#define CARELINK_IDS()			\
+	{ USB_DEVICE(0x0a21, 0x8001) }	/* MMT-7305WW */
+DEVICE(carelink, CARELINK_IDS);
+
+/* Infineon Flashloader driver */
+#define FLASHLOADER_IDS()		\
+	{ USB_DEVICE_INTERFACE_CLASS(0x058b, 0x0041, USB_CLASS_CDC_DATA) }, \
+	{ USB_DEVICE(0x8087, 0x0716) }, \
+	{ USB_DEVICE(0x8087, 0x0801) }
+DEVICE(flashloader, FLASHLOADER_IDS);
+
+/* Funsoft Serial USB driver */
+#define FUNSOFT_IDS()			\
+	{ USB_DEVICE(0x1404, 0xcddc) }
+DEVICE(funsoft, FUNSOFT_IDS);
+
+/* Google Serial USB SubClass */
+#define GOOGLE_IDS()						\
+	{ USB_VENDOR_AND_INTERFACE_INFO(0x18d1,			\
+					USB_CLASS_VENDOR_SPEC,	\
+					0x50,			\
+					0x01) }
+DEVICE(google, GOOGLE_IDS);
+
+/* HP4x (48/49) Generic Serial driver */
+#define HP4X_IDS()			\
+	{ USB_DEVICE(0x03f0, 0x0121) }
+DEVICE(hp4x, HP4X_IDS);
+
+/* KAUFMANN RKS+CAN VCP */
+#define KAUFMANN_IDS()			\
+	{ USB_DEVICE(0x16d0, 0x0870) }
+DEVICE(kaufmann, KAUFMANN_IDS);
+
+/* Libtransistor USB console */
+#define LIBTRANSISTOR_IDS()			\
+	{ USB_DEVICE(0x1209, 0x8b00) }
+DEVICE(libtransistor, LIBTRANSISTOR_IDS);
+
+/* Motorola USB Phone driver */
+#define MOTO_IDS()			\
+	{ USB_DEVICE(0x05c6, 0x3197) },	/* unknown Motorola phone */	\
+	{ USB_DEVICE(0x0c44, 0x0022) },	/* unknown Motorola phone */	\
+	{ USB_DEVICE(0x22b8, 0x2a64) },	/* Motorola KRZR K1m */		\
+	{ USB_DEVICE(0x22b8, 0x2c84) },	/* Motorola VE240 phone */	\
+	{ USB_DEVICE(0x22b8, 0x2c64) }	/* Motorola V950 phone */
+DEVICE(moto_modem, MOTO_IDS);
+
+/* Motorola Tetra driver */
+#define MOTOROLA_TETRA_IDS()			\
+	{ USB_DEVICE(0x0cad, 0x9011) },	/* Motorola Solutions TETRA PEI */ \
+	{ USB_DEVICE(0x0cad, 0x9012) },	/* MTP6550 */ \
+	{ USB_DEVICE(0x0cad, 0x9013) },	/* MTP3xxx */ \
+	{ USB_DEVICE(0x0cad, 0x9015) },	/* MTP85xx */ \
+	{ USB_DEVICE(0x0cad, 0x9016) }	/* TPG2200 */
+DEVICE(motorola_tetra, MOTOROLA_TETRA_IDS);
+
+/* Nokia mobile phone driver */
+#define NOKIA_IDS()			\
+	{ USB_DEVICE(0x0421, 0x069a) }	/* Nokia 130 (RM-1035) */
+DEVICE(nokia, NOKIA_IDS);
+
+/* Novatel Wireless GPS driver */
+#define NOVATEL_IDS()			\
+	{ USB_DEVICE(0x09d7, 0x0100) }	/* NovAtel FlexPack GPS */
+DEVICE_N(novatel_gps, NOVATEL_IDS, 3);
+
+/* OWON electronic test and measurement equipment driver */
+#define OWON_IDS()			\
+	{ USB_DEVICE(0x5345, 0x1234) } /* HDS200 oscilloscopes and others */
+DEVICE(owon, OWON_IDS);
+
+/* Siemens USB/MPI adapter */
+#define SIEMENS_IDS()			\
+	{ USB_DEVICE(0x908, 0x0004) }
+DEVICE(siemens_mpi, SIEMENS_IDS);
+
+/* Suunto ANT+ USB Driver */
+#define SUUNTO_IDS()			\
+	{ USB_DEVICE(0x0fcf, 0x1008) },	\
+	{ USB_DEVICE(0x0fcf, 0x1009) } /* Dynastream ANT USB-m Stick */
+DEVICE(suunto, SUUNTO_IDS);
+
+/* ViVOpay USB Serial Driver */
+#define VIVOPAY_IDS()			\
+	{ USB_DEVICE(0x1d5f, 0x1004) }	/* ViVOpay 8800 */
+DEVICE(vivopay, VIVOPAY_IDS);
+
+/* ZIO Motherboard USB driver */
+#define ZIO_IDS()			\
+	{ USB_DEVICE(0x1CBE, 0x0103) }
+DEVICE(zio, ZIO_IDS);
+
+/* All of the above structures mushed into two lists */
+static struct usb_serial_driver * const serial_drivers[] = {
+	&carelink_device,
+	&flashloader_device,
+	&funsoft_device,
+	&google_device,
+	&hp4x_device,
+	&kaufmann_device,
+	&libtransistor_device,
+	&moto_modem_device,
+	&motorola_tetra_device,
+	&nokia_device,
+	&novatel_gps_device,
+	&owon_device,
+	&siemens_mpi_device,
+	&suunto_device,
+	&vivopay_device,
+	&zio_device,
+	NULL
+};
+
+static const struct usb_device_id id_table[] = {
+	CARELINK_IDS(),
+	FLASHLOADER_IDS(),
+	FUNSOFT_IDS(),
+	GOOGLE_IDS(),
+	HP4X_IDS(),
+	KAUFMANN_IDS(),
+	LIBTRANSISTOR_IDS(),
+	MOTO_IDS(),
+	MOTOROLA_TETRA_IDS(),
+	NOKIA_IDS(),
+	NOVATEL_IDS(),
+	OWON_IDS(),
+	SIEMENS_IDS(),
+	SUUNTO_IDS(),
+	VIVOPAY_IDS(),
+	ZIO_IDS(),
+	{ },
+};
+MODULE_DEVICE_TABLE(usb, id_table);
+
+module_usb_serial_driver(serial_drivers, id_table);
+MODULE_DESCRIPTION("USB Serial 'Simple' driver");
+MODULE_LICENSE("GPL v2");