Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next

Johan Hedberg says:

====================
pull request: bluetooth-next 2018-06-04

Here's one last bluetooth-next pull request for the 4.18 kernel:

 - New USB device IDs for Realtek 8822BE and 8723DE
 - reset/resume fix for Dell Inspiron 5565
 - Fix HCI_UART_INIT_PENDING flag behavior
 - Fix patching behavior for some ATH3012 models
 - A few other minor cleanups & fixes

Please let me know if there are any issues pulling. Thanks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/bluetooth/btmrvl_debugfs.c

@@ -35,15 +35,9 @@ static ssize_t btmrvl_hscfgcmd_write(struct file *file,
 			const char __user *ubuf, size_t count, loff_t *ppos)
 {
 	struct btmrvl_private *priv = file->private_data;
-	char buf[16];
 	long result, ret;
 
-	memset(buf, 0, sizeof(buf));
-
-	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
-		return -EFAULT;
-
-	ret = kstrtol(buf, 10, &result);
+	ret = kstrtol_from_user(ubuf, count, 10, &result);
 	if (ret)
 		return ret;
 
@@ -81,15 +75,9 @@ static ssize_t btmrvl_pscmd_write(struct file *file, const char __user *ubuf,
 						size_t count, loff_t *ppos)
 {
 	struct btmrvl_private *priv = file->private_data;
-	char buf[16];
 	long result, ret;
 
-	memset(buf, 0, sizeof(buf));
-
-	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
-		return -EFAULT;
-
-	ret = kstrtol(buf, 10, &result);
+	ret = kstrtol_from_user(ubuf, count, 10, &result);
 	if (ret)
 		return ret;
 
@@ -127,15 +115,9 @@ static ssize_t btmrvl_hscmd_write(struct file *file, const char __user *ubuf,
 						size_t count, loff_t *ppos)
 {
 	struct btmrvl_private *priv = file->private_data;
-	char buf[16];
 	long result, ret;
 
-	memset(buf, 0, sizeof(buf));
-
-	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
-		return -EFAULT;
-
-	ret = kstrtol(buf, 10, &result);
+	ret = kstrtol_from_user(ubuf, count, 10, &result);
 	if (ret)
 		return ret;
 
@@ -167,35 +149,6 @@ static const struct file_operations btmrvl_hscmd_fops = {
 	.llseek = default_llseek,
 };
 
-static ssize_t btmrvl_fwdump_write(struct file *file, const char __user *ubuf,
-				   size_t count, loff_t *ppos)
-{
-	struct btmrvl_private *priv = file->private_data;
-	char buf[16];
-	bool result;
-
-	memset(buf, 0, sizeof(buf));
-
-	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
-		return -EFAULT;
-
-	if (strtobool(buf, &result))
-		return -EINVAL;
-
-	if (!result)
-		return -EINVAL;
-
-	btmrvl_firmware_dump(priv);
-
-	return count;
-}
-
-static const struct file_operations btmrvl_fwdump_fops = {
-	.write	= btmrvl_fwdump_write,
-	.open	= simple_open,
-	.llseek = default_llseek,
-};
-
 void btmrvl_debugfs_init(struct hci_dev *hdev)
 {
 	struct btmrvl_private *priv = hci_get_drvdata(hdev);
@@ -226,8 +179,6 @@ void btmrvl_debugfs_init(struct hci_dev *hdev)
 			    priv, &btmrvl_hscmd_fops);
 	debugfs_create_file("hscfgcmd", 0644, dbg->config_dir,
 			    priv, &btmrvl_hscfgcmd_fops);
-	debugfs_create_file("fw_dump", 0200, dbg->config_dir,
-			    priv, &btmrvl_fwdump_fops);
 
 	dbg->status_dir = debugfs_create_dir("status", hdev->debugfs);
 	debugfs_create_u8("curpsmode", 0444, dbg->status_dir,

drivers/bluetooth/btmrvl_drv.h

@@ -110,7 +110,6 @@ struct btmrvl_private {
 				u8 *payload, u16 nb);
 	int (*hw_wakeup_firmware)(struct btmrvl_private *priv);
 	int (*hw_process_int_status)(struct btmrvl_private *priv);
-	void (*firmware_dump)(struct btmrvl_private *priv);
 	spinlock_t driver_lock;		/* spinlock used by driver */
 #ifdef CONFIG_DEBUG_FS
 	void *debugfs_data;
@@ -183,7 +182,6 @@ int btmrvl_send_hscfg_cmd(struct btmrvl_private *priv);
 int btmrvl_enable_ps(struct btmrvl_private *priv);
 int btmrvl_prepare_command(struct btmrvl_private *priv);
 int btmrvl_enable_hs(struct btmrvl_private *priv);
-void btmrvl_firmware_dump(struct btmrvl_private *priv);
 
 #ifdef CONFIG_DEBUG_FS
 void btmrvl_debugfs_init(struct hci_dev *hdev);

drivers/bluetooth/btmrvl_main.c

@@ -358,12 +358,6 @@ int btmrvl_prepare_command(struct btmrvl_private *priv)
 	return ret;
 }
 
-void btmrvl_firmware_dump(struct btmrvl_private *priv)
-{
-	if (priv->firmware_dump)
-		priv->firmware_dump(priv);
-}
-
 static int btmrvl_tx_pkt(struct btmrvl_private *priv, struct sk_buff *skb)
 {
 	int ret = 0;

drivers/bluetooth/btmrvl_sdio.c

@@ -1311,9 +1311,11 @@ rdwr_status btmrvl_sdio_rdwr_firmware(struct btmrvl_private *priv,
 }
 
 /* This function dump sdio register and memory data */
-static void btmrvl_sdio_dump_firmware(struct btmrvl_private *priv)
+static void btmrvl_sdio_coredump(struct device *dev)
 {
-	struct btmrvl_sdio_card *card = priv->btmrvl_dev.card;
+	struct sdio_func *func = dev_to_sdio_func(dev);
+	struct btmrvl_sdio_card *card;
+	struct btmrvl_private *priv;
 	int ret = 0;
 	unsigned int reg, reg_start, reg_end;
 	enum rdwr_status stat;
@@ -1321,6 +1323,9 @@ static void btmrvl_sdio_dump_firmware(struct btmrvl_private *priv)
 	u8 dump_num = 0, idx, i, read_reg, doneflag = 0;
 	u32 memory_size, fw_dump_len = 0;
 
+	card = sdio_get_drvdata(func);
+	priv = card->priv;
+
 	/* dump sdio register first */
 	btmrvl_sdio_dump_regs(priv);
 
@@ -1547,7 +1552,6 @@ static int btmrvl_sdio_probe(struct sdio_func *func,
 	priv->hw_host_to_card = btmrvl_sdio_host_to_card;
 	priv->hw_wakeup_firmware = btmrvl_sdio_wakeup_fw;
 	priv->hw_process_int_status = btmrvl_sdio_process_int_status;
-	priv->firmware_dump = btmrvl_sdio_dump_firmware;
 
 	if (btmrvl_register_hdev(priv)) {
 		BT_ERR("Register hdev failed!");
@@ -1717,6 +1721,7 @@ static struct sdio_driver bt_mrvl_sdio = {
 	.remove		= btmrvl_sdio_remove,
 	.drv = {
 		.owner = THIS_MODULE,
+		.coredump = btmrvl_sdio_coredump,
 		.pm = &btmrvl_sdio_pm_ops,
 	}
 };

drivers/bluetooth/btusb.c

@@ -373,6 +373,9 @@ static const struct usb_device_id blacklist_table[] = {
 	/* Additional Realtek 8723BU Bluetooth devices */
 	{ USB_DEVICE(0x7392, 0xa611), .driver_info = BTUSB_REALTEK },
 
+	/* Additional Realtek 8723DE Bluetooth devices */
+	{ USB_DEVICE(0x2ff8, 0xb011), .driver_info = BTUSB_REALTEK },
+
 	/* Additional Realtek 8821AE Bluetooth devices */
 	{ USB_DEVICE(0x0b05, 0x17dc), .driver_info = BTUSB_REALTEK },
 	{ USB_DEVICE(0x13d3, 0x3414), .driver_info = BTUSB_REALTEK },
@@ -381,6 +384,7 @@ static const struct usb_device_id blacklist_table[] = {
 	{ USB_DEVICE(0x13d3, 0x3462), .driver_info = BTUSB_REALTEK },
 
 	/* Additional Realtek 8822BE Bluetooth devices */
+	{ USB_DEVICE(0x13d3, 0x3526), .driver_info = BTUSB_REALTEK },
 	{ USB_DEVICE(0x0b05, 0x185c), .driver_info = BTUSB_REALTEK },
 
 	/* Silicon Wave based devices */
@@ -408,6 +412,13 @@ static const struct dmi_system_id btusb_needs_reset_resume_table[] = {
 			DMI_MATCH(DMI_PRODUCT_NAME, "XPS 13 9360"),
 		},
 	},
+	{
+		/* Dell Inspiron 5565 (QCA ROME device 0cf3:e009) */
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 5565"),
+		},
+	},
 	{}
 };
 
@@ -2499,11 +2510,9 @@ static const struct qca_device_info qca_devices_table[] = {
 	{ 0x00000302, 28, 4, 18 }, /* Rome 3.2 */
 };
 
-static int btusb_qca_send_vendor_req(struct hci_dev *hdev, u8 request,
+static int btusb_qca_send_vendor_req(struct usb_device *udev, u8 request,
 				     void *data, u16 size)
 {
-	struct btusb_data *btdata = hci_get_drvdata(hdev);
-	struct usb_device *udev = btdata->udev;
 	int pipe, err;
 	u8 *buf;
 
@@ -2518,7 +2527,7 @@ static int btusb_qca_send_vendor_req(struct hci_dev *hdev, u8 request,
 	err = usb_control_msg(udev, pipe, request, USB_TYPE_VENDOR | USB_DIR_IN,
 			      0, 0, buf, size, USB_CTRL_SET_TIMEOUT);
 	if (err < 0) {
-		bt_dev_err(hdev, "Failed to access otp area (%d)", err);
+		dev_err(&udev->dev, "Failed to access otp area (%d)", err);
 		goto done;
 	}
 
@@ -2668,20 +2677,38 @@ static int btusb_setup_qca_load_nvm(struct hci_dev *hdev,
 	return err;
 }
 
+/* identify the ROM version and check whether patches are needed */
+static bool btusb_qca_need_patch(struct usb_device *udev)
+{
+	struct qca_version ver;
+
+	if (btusb_qca_send_vendor_req(udev, QCA_GET_TARGET_VERSION, &ver,
+				      sizeof(ver)) < 0)
+		return false;
+	/* only low ROM versions need patches */
+	return !(le32_to_cpu(ver.rom_version) & ~0xffffU);
+}
+
 static int btusb_setup_qca(struct hci_dev *hdev)
 {
+	struct btusb_data *btdata = hci_get_drvdata(hdev);
+	struct usb_device *udev = btdata->udev;
 	const struct qca_device_info *info = NULL;
 	struct qca_version ver;
 	u32 ver_rom;
 	u8 status;
 	int i, err;
 
-	err = btusb_qca_send_vendor_req(hdev, QCA_GET_TARGET_VERSION, &ver,
+	err = btusb_qca_send_vendor_req(udev, QCA_GET_TARGET_VERSION, &ver,
 					sizeof(ver));
 	if (err < 0)
 		return err;
 
 	ver_rom = le32_to_cpu(ver.rom_version);
+	/* Don't care about high ROM versions */
+	if (ver_rom & ~0xffffU)
+		return 0;
+
 	for (i = 0; i < ARRAY_SIZE(qca_devices_table); i++) {
 		if (ver_rom == qca_devices_table[i].rom_version)
 			info = &qca_devices_table[i];
@@ -2691,7 +2718,7 @@ static int btusb_setup_qca(struct hci_dev *hdev)
 		return -ENODEV;
 	}
 
-	err = btusb_qca_send_vendor_req(hdev, QCA_CHECK_STATUS, &status,
+	err = btusb_qca_send_vendor_req(udev, QCA_CHECK_STATUS, &status,
 					sizeof(status));
 	if (err < 0)
 		return err;
@@ -2905,7 +2932,8 @@ static int btusb_probe(struct usb_interface *intf,
 		/* Old firmware would otherwise let ath3k driver load
 		 * patch and sysconfig files
 		 */
-		if (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x0001)
+		if (le16_to_cpu(udev->descriptor.bcdDevice) <= 0x0001 &&
+		    !btusb_qca_need_patch(udev))
 			return -ENODEV;
 	}
 
@@ -3067,6 +3095,7 @@ static int btusb_probe(struct usb_interface *intf,
 	}
 
 	if (id->driver_info & BTUSB_ATH3012) {
+		data->setup_on_usb = btusb_setup_qca;
 		hdev->set_bdaddr = btusb_set_bdaddr_ath3012;
 		set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
 		set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);

drivers/bluetooth/hci_bcm.c

@@ -380,10 +380,6 @@ static int bcm_open(struct hci_uart *hu)
 	mutex_lock(&bcm_device_lock);
 
 	if (hu->serdev) {
-		err = serdev_device_open(hu->serdev);
-		if (err)
-			goto err_free;
-
 		bcm->dev = serdev_device_get_drvdata(hu->serdev);
 		goto out;
 	}
@@ -420,13 +416,10 @@ out:
 	return 0;
 
 err_unset_hu:
-	if (hu->serdev)
-		serdev_device_close(hu->serdev);
 #ifdef CONFIG_PM
-	else
+	if (!hu->serdev)
 		bcm->dev->hu = NULL;
 #endif
-err_free:
 	mutex_unlock(&bcm_device_lock);
 	hu->priv = NULL;
 	kfree(bcm);
@@ -445,7 +438,6 @@ static int bcm_close(struct hci_uart *hu)
 	mutex_lock(&bcm_device_lock);
 
 	if (hu->serdev) {
-		serdev_device_close(hu->serdev);
 		bdev = serdev_device_get_drvdata(hu->serdev);
 	} else if (bcm_device_exists(bcm->dev)) {
 		bdev = bcm->dev;

drivers/bluetooth/hci_ldisc.c

@@ -195,7 +195,7 @@ restart:
 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
 }
 
-static void hci_uart_init_work(struct work_struct *work)
+void hci_uart_init_work(struct work_struct *work)
 {
 	struct hci_uart *hu = container_of(work, struct hci_uart, init_ready);
 	int err;
@@ -229,15 +229,6 @@ int hci_uart_init_ready(struct hci_uart *hu)
 }
 
 /* ------- Interface to HCI layer ------ */
-/* Initialize device */
-static int hci_uart_open(struct hci_dev *hdev)
-{
-	BT_DBG("%s %p", hdev->name, hdev);
-
-	/* Nothing to do for UART driver */
-	return 0;
-}
-
 /* Reset device */
 static int hci_uart_flush(struct hci_dev *hdev)
 {
@@ -264,6 +255,17 @@ static int hci_uart_flush(struct hci_dev *hdev)
 	return 0;
 }
 
+/* Initialize device */
+static int hci_uart_open(struct hci_dev *hdev)
+{
+	BT_DBG("%s %p", hdev->name, hdev);
+
+	/* Undo clearing this from hci_uart_close() */
+	hdev->flush = hci_uart_flush;
+
+	return 0;
+}
+
 /* Close device */
 static int hci_uart_close(struct hci_dev *hdev)
 {

drivers/bluetooth/hci_ll.c

@@ -141,7 +141,6 @@ static int ll_open(struct hci_uart *hu)
 
 	if (hu->serdev) {
 		struct ll_device *lldev = serdev_device_get_drvdata(hu->serdev);
-		serdev_device_open(hu->serdev);
 		if (!IS_ERR(lldev->ext_clk))
 			clk_prepare_enable(lldev->ext_clk);
 	}
@@ -179,8 +178,6 @@ static int ll_close(struct hci_uart *hu)
 		gpiod_set_value_cansleep(lldev->enable_gpio, 0);
 
 		clk_disable_unprepare(lldev->ext_clk);
-
-		serdev_device_close(hu->serdev);
 	}
 
 	hu->priv = NULL;

drivers/bluetooth/hci_nokia.c

@@ -477,8 +477,6 @@ static int nokia_open(struct hci_uart *hu)
 
 	dev_dbg(dev, "protocol open");
 
-	serdev_device_open(hu->serdev);
-
 	pm_runtime_enable(dev);
 
 	return 0;
@@ -513,7 +511,6 @@ static int nokia_close(struct hci_uart *hu)
 	gpiod_set_value(btdev->wakeup_bt, 0);
 
 	pm_runtime_disable(&btdev->serdev->dev);
-	serdev_device_close(btdev->serdev);
 
 	return 0;
 }

drivers/bluetooth/hci_qca.c

@@ -910,7 +910,7 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate)
 	 */
 	set_current_state(TASK_UNINTERRUPTIBLE);
 	schedule_timeout(msecs_to_jiffies(BAUDRATE_SETTLE_TIMEOUT_MS));
-	set_current_state(TASK_INTERRUPTIBLE);
+	set_current_state(TASK_RUNNING);
 
 	return 0;
 }

drivers/bluetooth/hci_serdev.c

@@ -101,14 +101,6 @@ static void hci_uart_write_work(struct work_struct *work)
 
 /* ------- Interface to HCI layer ------ */
 
-/* Initialize device */
-static int hci_uart_open(struct hci_dev *hdev)
-{
-	BT_DBG("%s %p", hdev->name, hdev);
-
-	return 0;
-}
-
 /* Reset device */
 static int hci_uart_flush(struct hci_dev *hdev)
 {
@@ -129,6 +121,17 @@ static int hci_uart_flush(struct hci_dev *hdev)
 	return 0;
 }
 
+/* Initialize device */
+static int hci_uart_open(struct hci_dev *hdev)
+{
+	BT_DBG("%s %p", hdev->name, hdev);
+
+	/* Undo clearing this from hci_uart_close() */
+	hdev->flush = hci_uart_flush;
+
+	return 0;
+}
+
 /* Close device */
 static int hci_uart_close(struct hci_dev *hdev)
 {
@@ -204,9 +207,8 @@ static int hci_uart_setup(struct hci_dev *hdev)
 		return 0;
 	}
 
-	if (skb->len != sizeof(*ver)) {
+	if (skb->len != sizeof(*ver))
 		bt_dev_err(hdev, "Event length mismatch for version info");
-	}
 
 	kfree_skb(skb);
 	return 0;
@@ -282,10 +284,14 @@ int hci_uart_register_device(struct hci_uart *hu,
 
 	serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops);
 
-	err = p->open(hu);
+	err = serdev_device_open(hu->serdev);
 	if (err)
 		return err;
 
+	err = p->open(hu);
+	if (err)
+		goto err_open;
+
 	hu->proto = p;
 	set_bit(HCI_UART_PROTO_READY, &hu->flags);
 
@@ -302,6 +308,7 @@ int hci_uart_register_device(struct hci_uart *hu,
 	hdev->bus = HCI_UART;
 	hci_set_drvdata(hdev, hu);
 
+	INIT_WORK(&hu->init_ready, hci_uart_init_work);
 	INIT_WORK(&hu->write_work, hci_uart_write_work);
 	percpu_init_rwsem(&hu->proto_lock);
 
@@ -351,6 +358,8 @@ err_register:
 err_alloc:
 	clear_bit(HCI_UART_PROTO_READY, &hu->flags);
 	p->close(hu);
+err_open:
+	serdev_device_close(hu->serdev);
 	return err;
 }
 EXPORT_SYMBOL_GPL(hci_uart_register_device);
@@ -365,5 +374,6 @@ void hci_uart_unregister_device(struct hci_uart *hu)
 	cancel_work_sync(&hu->write_work);
 
 	hu->proto->close(hu);
+	serdev_device_close(hu->serdev);
 }
 EXPORT_SYMBOL_GPL(hci_uart_unregister_device);

drivers/bluetooth/hci_uart.h

@@ -116,6 +116,7 @@ void hci_uart_unregister_device(struct hci_uart *hu);
 
 int hci_uart_tx_wakeup(struct hci_uart *hu);
 int hci_uart_init_ready(struct hci_uart *hu);
+void hci_uart_init_work(struct work_struct *work);
 void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed);
 void hci_uart_set_flow_control(struct hci_uart *hu, bool enable);
 void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,

net/bluetooth/hci_core.c

@@ -76,19 +76,15 @@ static ssize_t dut_mode_write(struct file *file, const char __user *user_buf,
 {
 	struct hci_dev *hdev = file->private_data;
 	struct sk_buff *skb;
-	char buf[32];
-	size_t buf_size = min(count, (sizeof(buf)-1));
 	bool enable;
+	int err;
 
 	if (!test_bit(HCI_UP, &hdev->flags))
 		return -ENETDOWN;
 
-	if (copy_from_user(buf, user_buf, buf_size))
-		return -EFAULT;
-
-	buf[buf_size] = '\0';
-	if (strtobool(buf, &enable))
-		return -EINVAL;
+	err = kstrtobool_from_user(user_buf, count, &enable);
+	if (err)
+		return err;
 
 	if (enable == hci_dev_test_flag(hdev, HCI_DUT_MODE))
 		return -EALREADY;
@@ -135,17 +131,12 @@ static ssize_t vendor_diag_write(struct file *file, const char __user *user_buf,
 				 size_t count, loff_t *ppos)
 {
 	struct hci_dev *hdev = file->private_data;
-	char buf[32];
-	size_t buf_size = min(count, (sizeof(buf)-1));
 	bool enable;
 	int err;
 
-	if (copy_from_user(buf, user_buf, buf_size))
-		return -EFAULT;
-
-	buf[buf_size] = '\0';
-	if (strtobool(buf, &enable))
-		return -EINVAL;
+	err = kstrtobool_from_user(user_buf, count, &enable);
+	if (err)
+		return err;
 
 	/* When the diagnostic flags are not persistent and the transport
 	 * is not active or in user channel operation, then there is no need

net/bluetooth/hci_debugfs.c

@@ -47,19 +47,15 @@ static ssize_t __name ## _write(struct file *file,			      \
 				 size_t count, loff_t *ppos)		      \
 {									      \
 	struct hci_dev *hdev = file->private_data;			      \
-	char buf[32];							      \
-	size_t buf_size = min(count, (sizeof(buf) - 1));		      \
 	bool enable;							      \
+	int err;							      \
 									      \
 	if (test_bit(HCI_UP, &hdev->flags))				      \
 		return -EBUSY;						      \
 									      \
-	if (copy_from_user(buf, user_buf, buf_size))			      \
-		return -EFAULT;						      \
-									      \
-	buf[buf_size] = '\0';						      \
-	if (strtobool(buf, &enable))					      \
-		return -EINVAL;						      \
+	err = kstrtobool_from_user(user_buf, count, &enable);		      \
+	if (err)							      \
+		return err;						      \
 									      \
 	if (enable == test_bit(__quirk, &hdev->quirks))			      \
 		return -EALREADY;					      \
@@ -658,19 +654,15 @@ static ssize_t force_static_address_write(struct file *file,
 					  size_t count, loff_t *ppos)
 {
 	struct hci_dev *hdev = file->private_data;
-	char buf[32];
-	size_t buf_size = min(count, (sizeof(buf)-1));
 	bool enable;
+	int err;
 
 	if (test_bit(HCI_UP, &hdev->flags))
 		return -EBUSY;
 
-	if (copy_from_user(buf, user_buf, buf_size))
-		return -EFAULT;
-
-	buf[buf_size] = '\0';
-	if (strtobool(buf, &enable))
-		return -EINVAL;
+	err = kstrtobool_from_user(user_buf, count, &enable);
+	if (err)
+		return err;
 
 	if (enable == hci_dev_test_flag(hdev, HCI_FORCE_STATIC_ADDR))
 		return -EALREADY;

net/bluetooth/smp.c

@@ -3315,16 +3315,12 @@ static ssize_t force_bredr_smp_write(struct file *file,
 				     size_t count, loff_t *ppos)
 {
 	struct hci_dev *hdev = file->private_data;
-	char buf[32];
-	size_t buf_size = min(count, (sizeof(buf)-1));
 	bool enable;
+	int err;
 
-	if (copy_from_user(buf, user_buf, buf_size))
-		return -EFAULT;
-
-	buf[buf_size] = '\0';
-	if (strtobool(buf, &enable))
-		return -EINVAL;
+	err = kstrtobool_from_user(user_buf, count, &enable);
+	if (err)
+		return err;
 
 	if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP))
 		return -EALREADY;