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, 367 insertions, 0 deletions

diff --git a/net/bluetooth/mgmt_config.c b/net/bluetooth/mgmt_config.c
new file mode 100644
index 000000000..fdcc752c6
--- /dev/null
+++ b/net/bluetooth/mgmt_config.c
@@ -0,0 +1,367 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+/*
+ * Copyright (C) 2020 Google Corporation
+ */
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/mgmt.h>
+
+#include "mgmt_util.h"
+#include "mgmt_config.h"
+
+#define HDEV_PARAM_U32(_param_name_) \
+	struct {\
+		struct mgmt_tlv_hdr entry; \
+		__le32 value; \
+	} __packed _param_name_
+
+#define HDEV_PARAM_U16(_param_name_) \
+	struct {\
+		struct mgmt_tlv_hdr entry; \
+		__le16 value; \
+	} __packed _param_name_
+
+#define HDEV_PARAM_U8(_param_name_) \
+	struct {\
+		struct mgmt_tlv_hdr entry; \
+		__u8 value; \
+	} __packed _param_name_
+
+#define TLV_SET_U16(_param_code_, _param_name_) \
+	{ \
+		{ cpu_to_le16(_param_code_), sizeof(__u16) }, \
+		cpu_to_le16(hdev->_param_name_) \
+	}
+
+#define TLV_SET_U32(_param_code_, _param_name_) \
+	{ \
+		{ cpu_to_le16(_param_code_), sizeof(__u32) }, \
+		cpu_to_le32(hdev->_param_name_) \
+	}
+
+#define TLV_SET_U8(_param_code_, _param_name_) \
+	{ \
+		{ cpu_to_le16(_param_code_), sizeof(__u8) }, \
+		hdev->_param_name_ \
+	}
+
+#define TLV_SET_U16_JIFFIES_TO_MSECS(_param_code_, _param_name_) \
+	{ \
+		{ cpu_to_le16(_param_code_), sizeof(__u16) }, \
+		cpu_to_le16(jiffies_to_msecs(hdev->_param_name_)) \
+	}
+
+int read_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
+			   u16 data_len)
+{
+	int ret;
+	struct mgmt_rp_read_def_system_config {
+		/* Please see mgmt-api.txt for documentation of these values */
+		HDEV_PARAM_U16(def_page_scan_type);
+		HDEV_PARAM_U16(def_page_scan_int);
+		HDEV_PARAM_U16(def_page_scan_window);
+		HDEV_PARAM_U16(def_inq_scan_type);
+		HDEV_PARAM_U16(def_inq_scan_int);
+		HDEV_PARAM_U16(def_inq_scan_window);
+		HDEV_PARAM_U16(def_br_lsto);
+		HDEV_PARAM_U16(def_page_timeout);
+		HDEV_PARAM_U16(sniff_min_interval);
+		HDEV_PARAM_U16(sniff_max_interval);
+		HDEV_PARAM_U16(le_adv_min_interval);
+		HDEV_PARAM_U16(le_adv_max_interval);
+		HDEV_PARAM_U16(def_multi_adv_rotation_duration);
+		HDEV_PARAM_U16(le_scan_interval);
+		HDEV_PARAM_U16(le_scan_window);
+		HDEV_PARAM_U16(le_scan_int_suspend);
+		HDEV_PARAM_U16(le_scan_window_suspend);
+		HDEV_PARAM_U16(le_scan_int_discovery);
+		HDEV_PARAM_U16(le_scan_window_discovery);
+		HDEV_PARAM_U16(le_scan_int_adv_monitor);
+		HDEV_PARAM_U16(le_scan_window_adv_monitor);
+		HDEV_PARAM_U16(le_scan_int_connect);
+		HDEV_PARAM_U16(le_scan_window_connect);
+		HDEV_PARAM_U16(le_conn_min_interval);
+		HDEV_PARAM_U16(le_conn_max_interval);
+		HDEV_PARAM_U16(le_conn_latency);
+		HDEV_PARAM_U16(le_supv_timeout);
+		HDEV_PARAM_U16(def_le_autoconnect_timeout);
+		HDEV_PARAM_U16(advmon_allowlist_duration);
+		HDEV_PARAM_U16(advmon_no_filter_duration);
+		HDEV_PARAM_U8(enable_advmon_interleave_scan);
+		HDEV_PARAM_U32(idle_timeout);
+	} __packed rp = {
+		TLV_SET_U16(0x0000, def_page_scan_type),
+		TLV_SET_U16(0x0001, def_page_scan_int),
+		TLV_SET_U16(0x0002, def_page_scan_window),
+		TLV_SET_U16(0x0003, def_inq_scan_type),
+		TLV_SET_U16(0x0004, def_inq_scan_int),
+		TLV_SET_U16(0x0005, def_inq_scan_window),
+		TLV_SET_U16(0x0006, def_br_lsto),
+		TLV_SET_U16(0x0007, def_page_timeout),
+		TLV_SET_U16(0x0008, sniff_min_interval),
+		TLV_SET_U16(0x0009, sniff_max_interval),
+		TLV_SET_U16(0x000a, le_adv_min_interval),
+		TLV_SET_U16(0x000b, le_adv_max_interval),
+		TLV_SET_U16(0x000c, def_multi_adv_rotation_duration),
+		TLV_SET_U16(0x000d, le_scan_interval),
+		TLV_SET_U16(0x000e, le_scan_window),
+		TLV_SET_U16(0x000f, le_scan_int_suspend),
+		TLV_SET_U16(0x0010, le_scan_window_suspend),
+		TLV_SET_U16(0x0011, le_scan_int_discovery),
+		TLV_SET_U16(0x0012, le_scan_window_discovery),
+		TLV_SET_U16(0x0013, le_scan_int_adv_monitor),
+		TLV_SET_U16(0x0014, le_scan_window_adv_monitor),
+		TLV_SET_U16(0x0015, le_scan_int_connect),
+		TLV_SET_U16(0x0016, le_scan_window_connect),
+		TLV_SET_U16(0x0017, le_conn_min_interval),
+		TLV_SET_U16(0x0018, le_conn_max_interval),
+		TLV_SET_U16(0x0019, le_conn_latency),
+		TLV_SET_U16(0x001a, le_supv_timeout),
+		TLV_SET_U16_JIFFIES_TO_MSECS(0x001b,
+					     def_le_autoconnect_timeout),
+		TLV_SET_U16(0x001d, advmon_allowlist_duration),
+		TLV_SET_U16(0x001e, advmon_no_filter_duration),
+		TLV_SET_U8(0x001f, enable_advmon_interleave_scan),
+		TLV_SET_U32(0x0020, idle_timeout),
+	};
+
+	bt_dev_dbg(hdev, "sock %p", sk);
+
+	ret = mgmt_cmd_complete(sk, hdev->id,
+				MGMT_OP_READ_DEF_SYSTEM_CONFIG,
+				0, &rp, sizeof(rp));
+	return ret;
+}
+
+#define TO_TLV(x)		((struct mgmt_tlv *)(x))
+#define TLV_GET_LE32(tlv)	le32_to_cpu(*((__le32 *)(TO_TLV(tlv)->value)))
+#define TLV_GET_LE16(tlv)	le16_to_cpu(*((__le16 *)(TO_TLV(tlv)->value)))
+#define TLV_GET_U8(tlv)		(*((__u8 *)(TO_TLV(tlv)->value)))
+
+int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
+			  u16 data_len)
+{
+	u16 buffer_left = data_len;
+	u8 *buffer = data;
+
+	if (buffer_left < sizeof(struct mgmt_tlv)) {
+		return mgmt_cmd_status(sk, hdev->id,
+				       MGMT_OP_SET_DEF_SYSTEM_CONFIG,
+				       MGMT_STATUS_INVALID_PARAMS);
+	}
+
+	/* First pass to validate the tlv */
+	while (buffer_left >= sizeof(struct mgmt_tlv)) {
+		const u8 len = TO_TLV(buffer)->length;
+		size_t exp_type_len;
+		const u16 exp_len = sizeof(struct mgmt_tlv) +
+				    len;
+		const u16 type = le16_to_cpu(TO_TLV(buffer)->type);
+
+		if (buffer_left < exp_len) {
+			bt_dev_warn(hdev, "invalid len left %u, exp >= %u",
+				    buffer_left, exp_len);
+
+			return mgmt_cmd_status(sk, hdev->id,
+					MGMT_OP_SET_DEF_SYSTEM_CONFIG,
+					MGMT_STATUS_INVALID_PARAMS);
+		}
+
+		/* Please see mgmt-api.txt for documentation of these values */
+		switch (type) {
+		case 0x0000:
+		case 0x0001:
+		case 0x0002:
+		case 0x0003:
+		case 0x0004:
+		case 0x0005:
+		case 0x0006:
+		case 0x0007:
+		case 0x0008:
+		case 0x0009:
+		case 0x000a:
+		case 0x000b:
+		case 0x000c:
+		case 0x000d:
+		case 0x000e:
+		case 0x000f:
+		case 0x0010:
+		case 0x0011:
+		case 0x0012:
+		case 0x0013:
+		case 0x0014:
+		case 0x0015:
+		case 0x0016:
+		case 0x0017:
+		case 0x0018:
+		case 0x0019:
+		case 0x001a:
+		case 0x001b:
+		case 0x001d:
+		case 0x001e:
+			exp_type_len = sizeof(u16);
+			break;
+		case 0x001f:
+			exp_type_len = sizeof(u8);
+			break;
+		case 0x0020:
+			exp_type_len = sizeof(u32);
+			break;
+		default:
+			exp_type_len = 0;
+			bt_dev_warn(hdev, "unsupported parameter %u", type);
+			break;
+		}
+
+		if (exp_type_len && len != exp_type_len) {
+			bt_dev_warn(hdev, "invalid length %d, exp %zu for type %u",
+				    len, exp_type_len, type);
+
+			return mgmt_cmd_status(sk, hdev->id,
+				MGMT_OP_SET_DEF_SYSTEM_CONFIG,
+				MGMT_STATUS_INVALID_PARAMS);
+		}
+
+		buffer_left -= exp_len;
+		buffer += exp_len;
+	}
+
+	buffer_left = data_len;
+	buffer = data;
+	while (buffer_left >= sizeof(struct mgmt_tlv)) {
+		const u8 len = TO_TLV(buffer)->length;
+		const u16 exp_len = sizeof(struct mgmt_tlv) +
+				    len;
+		const u16 type = le16_to_cpu(TO_TLV(buffer)->type);
+
+		switch (type) {
+		case 0x0000:
+			hdev->def_page_scan_type = TLV_GET_LE16(buffer);
+			break;
+		case 0x0001:
+			hdev->def_page_scan_int = TLV_GET_LE16(buffer);
+			break;
+		case 0x0002:
+			hdev->def_page_scan_window = TLV_GET_LE16(buffer);
+			break;
+		case 0x0003:
+			hdev->def_inq_scan_type = TLV_GET_LE16(buffer);
+			break;
+		case 0x0004:
+			hdev->def_inq_scan_int = TLV_GET_LE16(buffer);
+			break;
+		case 0x0005:
+			hdev->def_inq_scan_window = TLV_GET_LE16(buffer);
+			break;
+		case 0x0006:
+			hdev->def_br_lsto = TLV_GET_LE16(buffer);
+			break;
+		case 0x0007:
+			hdev->def_page_timeout = TLV_GET_LE16(buffer);
+			break;
+		case 0x0008:
+			hdev->sniff_min_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x0009:
+			hdev->sniff_max_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x000a:
+			hdev->le_adv_min_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x000b:
+			hdev->le_adv_max_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x000c:
+			hdev->def_multi_adv_rotation_duration =
+							   TLV_GET_LE16(buffer);
+			break;
+		case 0x000d:
+			hdev->le_scan_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x000e:
+			hdev->le_scan_window = TLV_GET_LE16(buffer);
+			break;
+		case 0x000f:
+			hdev->le_scan_int_suspend = TLV_GET_LE16(buffer);
+			break;
+		case 0x0010:
+			hdev->le_scan_window_suspend = TLV_GET_LE16(buffer);
+			break;
+		case 0x0011:
+			hdev->le_scan_int_discovery = TLV_GET_LE16(buffer);
+			break;
+		case 0x00012:
+			hdev->le_scan_window_discovery = TLV_GET_LE16(buffer);
+			break;
+		case 0x00013:
+			hdev->le_scan_int_adv_monitor = TLV_GET_LE16(buffer);
+			break;
+		case 0x00014:
+			hdev->le_scan_window_adv_monitor = TLV_GET_LE16(buffer);
+			break;
+		case 0x00015:
+			hdev->le_scan_int_connect = TLV_GET_LE16(buffer);
+			break;
+		case 0x00016:
+			hdev->le_scan_window_connect = TLV_GET_LE16(buffer);
+			break;
+		case 0x00017:
+			hdev->le_conn_min_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x00018:
+			hdev->le_conn_max_interval = TLV_GET_LE16(buffer);
+			break;
+		case 0x00019:
+			hdev->le_conn_latency = TLV_GET_LE16(buffer);
+			break;
+		case 0x0001a:
+			hdev->le_supv_timeout = TLV_GET_LE16(buffer);
+			break;
+		case 0x0001b:
+			hdev->def_le_autoconnect_timeout =
+					msecs_to_jiffies(TLV_GET_LE16(buffer));
+			break;
+		case 0x0001d:
+			hdev->advmon_allowlist_duration = TLV_GET_LE16(buffer);
+			break;
+		case 0x0001e:
+			hdev->advmon_no_filter_duration = TLV_GET_LE16(buffer);
+			break;
+		case 0x0001f:
+			hdev->enable_advmon_interleave_scan = TLV_GET_U8(buffer);
+			break;
+		case 0x00020:
+			hdev->idle_timeout = TLV_GET_LE32(buffer);
+			break;
+		default:
+			bt_dev_warn(hdev, "unsupported parameter %u", type);
+			break;
+		}
+
+		buffer_left -= exp_len;
+		buffer += exp_len;
+	}
+
+	return mgmt_cmd_complete(sk, hdev->id,
+				 MGMT_OP_SET_DEF_SYSTEM_CONFIG, 0, NULL, 0);
+}
+
+int read_def_runtime_config(struct sock *sk, struct hci_dev *hdev, void *data,
+			    u16 data_len)
+{
+	bt_dev_dbg(hdev, "sock %p", sk);
+
+	return mgmt_cmd_complete(sk, hdev->id,
+				 MGMT_OP_READ_DEF_RUNTIME_CONFIG, 0, NULL, 0);
+}
+
+int set_def_runtime_config(struct sock *sk, struct hci_dev *hdev, void *data,
+			   u16 data_len)
+{
+	bt_dev_dbg(hdev, "sock %p", sk);
+
+	return mgmt_cmd_status(sk, hdev->id, MGMT_OP_SET_DEF_SYSTEM_CONFIG,
+			       MGMT_STATUS_INVALID_PARAMS);
+}