1 files changed, 214 insertions, 126 deletions

diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c
index ec530454e6f6..bbd6f23bce78 100644
--- a/drivers/hid/hidraw.c
+++ b/drivers/hid/hidraw.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * HID raw devices, giving access to raw HID events.
  *
@@ -9,15 +10,6 @@
  *  Copyright (c) 2007-2014 Jiri Kosina
  */
 
-/*
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
@@ -40,9 +32,16 @@
 
 static int hidraw_major;
 static struct cdev hidraw_cdev;
-static struct class *hidraw_class;
+static const struct class hidraw_class = {
+	.name = "hidraw",
+};
 static struct hidraw *hidraw_table[HIDRAW_MAX_DEVICES];
-static DEFINE_MUTEX(minors_lock);
+static DECLARE_RWSEM(minors_rwsem);
+
+static inline bool hidraw_is_revoked(struct hidraw_list *list)
+{
+	return list->revoked;
+}
 
 static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
 {
@@ -50,6 +49,9 @@ static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count,
 	int ret = 0, len;
 	DECLARE_WAITQUEUE(wait, current);
 
+	if (hidraw_is_revoked(list))
+		return -ENODEV;
+
 	mutex_lock(&list->read_mutex);
 
 	while (ret == 0) {
@@ -107,8 +109,6 @@ out:
 
 /*
  * The first byte of the report buffer is expected to be a report number.
- *
- * This function is to be called with the minors_lock mutex held.
  */
 static ssize_t hidraw_send_report(struct file *file, const char __user *buffer, size_t count, unsigned char report_type)
 {
@@ -117,6 +117,8 @@ static ssize_t hidraw_send_report(struct file *file, const char __user *buffer,
 	__u8 *buf;
 	int ret = 0;
 
+	lockdep_assert_held(&minors_rwsem);
+
 	if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
 		ret = -ENODEV;
 		goto out;
@@ -146,7 +148,7 @@ static ssize_t hidraw_send_report(struct file *file, const char __user *buffer,
 
 	if ((report_type == HID_OUTPUT_REPORT) &&
 	    !(dev->quirks & HID_QUIRK_NO_OUTPUT_REPORTS_ON_INTR_EP)) {
-		ret = hid_hw_output_report(dev, buf, count);
+		ret = __hid_hw_output_report(dev, buf, count, (u64)(long)file, false);
 		/*
 		 * compatibility with old implementation of USB-HID and I2C-HID:
 		 * if the device does not support receiving output reports,
@@ -156,8 +158,8 @@ static ssize_t hidraw_send_report(struct file *file, const char __user *buffer,
 			goto out_free;
 	}
 
-	ret = hid_hw_raw_request(dev, buf[0], buf, count, report_type,
-				HID_REQ_SET_REPORT);
+	ret = __hid_hw_raw_request(dev, buf[0], buf, count, report_type,
+				   HID_REQ_SET_REPORT, (u64)(long)file, false);
 
 out_free:
 	kfree(buf);
@@ -167,10 +169,14 @@ out:
 
 static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 {
+	struct hidraw_list *list = file->private_data;
 	ssize_t ret;
-	mutex_lock(&minors_lock);
-	ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
-	mutex_unlock(&minors_lock);
+	down_read(&minors_rwsem);
+	if (hidraw_is_revoked(list))
+		ret = -ENODEV;
+	else
+		ret = hidraw_send_report(file, buffer, count, HID_OUTPUT_REPORT);
+	up_read(&minors_rwsem);
 	return ret;
 }
 
@@ -178,11 +184,9 @@ static ssize_t hidraw_write(struct file *file, const char __user *buffer, size_t
 /*
  * This function performs a Get_Report transfer over the control endpoint
  * per section 7.2.1 of the HID specification, version 1.1.  The first byte
- * of buffer is the report number to request, or 0x0 if the defice does not
+ * of buffer is the report number to request, or 0x0 if the device does not
  * use numbered reports. The report_type parameter can be HID_FEATURE_REPORT
  * or HID_INPUT_REPORT.
- *
- * This function is to be called with the minors_lock mutex held.
  */
 static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t count, unsigned char report_type)
 {
@@ -192,6 +196,13 @@ static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t
 	int ret = 0, len;
 	unsigned char report_number;
 
+	lockdep_assert_held(&minors_rwsem);
+
+	if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
+		ret = -ENODEV;
+		goto out;
+	}
+
 	dev = hidraw_table[minor]->hid;
 
 	if (!dev->ll_driver->raw_request) {
@@ -200,20 +211,20 @@ static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t
 	}
 
 	if (count > HID_MAX_BUFFER_SIZE) {
-		printk(KERN_WARNING "hidraw: pid %d passed too large report\n",
-				task_pid_nr(current));
+		hid_warn(dev, "pid %d passed too large report\n",
+			task_pid_nr(current));
 		ret = -EINVAL;
 		goto out;
 	}
 
 	if (count < 2) {
-		printk(KERN_WARNING "hidraw: pid %d passed too short report\n",
-				task_pid_nr(current));
+		hid_warn(dev, "pid %d passed too short report\n",
+			task_pid_nr(current));
 		ret = -EINVAL;
 		goto out;
 	}
 
-	buf = kmalloc(count * sizeof(__u8), GFP_KERNEL);
+	buf = kmalloc(count, GFP_KERNEL);
 	if (!buf) {
 		ret = -ENOMEM;
 		goto out;
@@ -228,8 +239,8 @@ static ssize_t hidraw_get_report(struct file *file, char __user *buffer, size_t
 		goto out_free;
 	}
 
-	ret = hid_hw_raw_request(dev, report_number, buf, count, report_type,
-				 HID_REQ_GET_REPORT);
+	ret = __hid_hw_raw_request(dev, report_number, buf, count, report_type,
+				   HID_REQ_GET_REPORT, (u64)(long)file, false);
 
 	if (ret < 0)
 		goto out_free;
@@ -249,16 +260,17 @@ out:
 	return ret;
 }
 
-static unsigned int hidraw_poll(struct file *file, poll_table *wait)
+static __poll_t hidraw_poll(struct file *file, poll_table *wait)
 {
 	struct hidraw_list *list = file->private_data;
+	__poll_t mask = EPOLLOUT | EPOLLWRNORM; /* hidraw is always writable */
 
 	poll_wait(file, &list->hidraw->wait, wait);
 	if (list->head != list->tail)
-		return POLLIN | POLLRDNORM;
-	if (!list->hidraw->exist)
-		return POLLERR | POLLHUP;
-	return 0;
+		mask |= EPOLLIN | EPOLLRDNORM;
+	if (!list->hidraw->exist || hidraw_is_revoked(list))
+		mask |= EPOLLERR | EPOLLHUP;
+	return mask;
 }
 
 static int hidraw_open(struct inode *inode, struct file *file)
@@ -274,7 +286,12 @@ static int hidraw_open(struct inode *inode, struct file *file)
 		goto out;
 	}
 
-	mutex_lock(&minors_lock);
+	/*
+	 * Technically not writing to the hidraw_table but a write lock is
+	 * required to protect the device refcount. This is symmetrical to
+	 * hidraw_release().
+	 */
+	down_write(&minors_rwsem);
 	if (!hidraw_table[minor] || !hidraw_table[minor]->exist) {
 		err = -ENODEV;
 		goto out_unlock;
@@ -303,7 +320,7 @@ static int hidraw_open(struct inode *inode, struct file *file)
 	spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
 	file->private_data = list;
 out_unlock:
-	mutex_unlock(&minors_lock);
+	up_write(&minors_rwsem);
 out:
 	if (err < 0)
 		kfree(list);
@@ -315,6 +332,9 @@ static int hidraw_fasync(int fd, struct file *file, int on)
 {
 	struct hidraw_list *list = file->private_data;
 
+	if (hidraw_is_revoked(list))
+		return -ENODEV;
+
 	return fasync_helper(fd, file, on, &list->fasync);
 }
 
@@ -326,7 +346,7 @@ static void drop_ref(struct hidraw *hidraw, int exists_bit)
 			hid_hw_close(hidraw->hid);
 			wake_up_interruptible(&hidraw->wait);
 		}
-		device_destroy(hidraw_class,
+		device_destroy(&hidraw_class,
 			       MKDEV(hidraw_major, hidraw->minor));
 	} else {
 		--hidraw->open;
@@ -337,8 +357,8 @@ static void drop_ref(struct hidraw *hidraw, int exists_bit)
 			kfree(hidraw);
 		} else {
 			/* close device for last reader */
-			hid_hw_power(hidraw->hid, PM_HINT_NORMAL);
 			hid_hw_close(hidraw->hid);
+			hid_hw_power(hidraw->hid, PM_HINT_NORMAL);
 		}
 	}
 }
@@ -349,39 +369,40 @@ static int hidraw_release(struct inode * inode, struct file * file)
 	struct hidraw_list *list = file->private_data;
 	unsigned long flags;
 
-	mutex_lock(&minors_lock);
+	down_write(&minors_rwsem);
 
 	spin_lock_irqsave(&hidraw_table[minor]->list_lock, flags);
+	while (list->tail != list->head) {
+		kfree(list->buffer[list->tail].value);
+		list->buffer[list->tail].value = NULL;
+		list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
+	}
 	list_del(&list->node);
 	spin_unlock_irqrestore(&hidraw_table[minor]->list_lock, flags);
 	kfree(list);
 
 	drop_ref(hidraw_table[minor], 0);
 
-	mutex_unlock(&minors_lock);
+	up_write(&minors_rwsem);
 	return 0;
 }
 
-static long hidraw_ioctl(struct file *file, unsigned int cmd,
-							unsigned long arg)
+static int hidraw_revoke(struct hidraw_list *list)
 {
-	struct inode *inode = file_inode(file);
-	unsigned int minor = iminor(inode);
-	long ret = 0;
-	struct hidraw *dev;
-	void __user *user_arg = (void __user*) arg;
+	list->revoked = true;
 
-	mutex_lock(&minors_lock);
-	dev = hidraw_table[minor];
-	if (!dev) {
-		ret = -ENODEV;
-		goto out;
-	}
+	return 0;
+}
+
+static long hidraw_fixed_size_ioctl(struct file *file, struct hidraw *dev, unsigned int cmd,
+				    void __user *arg)
+{
+	struct hid_device *hid = dev->hid;
 
 	switch (cmd) {
 		case HIDIOCGRDESCSIZE:
-			if (put_user(dev->hid->rsize, (int __user *)arg))
-				ret = -EFAULT;
+			if (put_user(hid->rsize, (int __user *)arg))
+				return -EFAULT;
 			break;
 
 		case HIDIOCGRDESC:
@@ -389,76 +410,147 @@ static long hidraw_ioctl(struct file *file, unsigned int cmd,
 				__u32 len;
 
 				if (get_user(len, (int __user *)arg))
-					ret = -EFAULT;
-				else if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
-					ret = -EINVAL;
-				else if (copy_to_user(user_arg + offsetof(
-					struct hidraw_report_descriptor,
-					value[0]),
-					dev->hid->rdesc,
-					min(dev->hid->rsize, len)))
-					ret = -EFAULT;
+					return -EFAULT;
+
+				if (len > HID_MAX_DESCRIPTOR_SIZE - 1)
+					return -EINVAL;
+
+				if (copy_to_user(arg + offsetof(
+				    struct hidraw_report_descriptor,
+				    value[0]),
+				    hid->rdesc,
+				    min(hid->rsize, len)))
+					return -EFAULT;
+
 				break;
 			}
 		case HIDIOCGRAWINFO:
 			{
 				struct hidraw_devinfo dinfo;
 
-				dinfo.bustype = dev->hid->bus;
-				dinfo.vendor = dev->hid->vendor;
-				dinfo.product = dev->hid->product;
-				if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
-					ret = -EFAULT;
+				dinfo.bustype = hid->bus;
+				dinfo.vendor = hid->vendor;
+				dinfo.product = hid->product;
+				if (copy_to_user(arg, &dinfo, sizeof(dinfo)))
+					return -EFAULT;
 				break;
 			}
-		default:
+		case HIDIOCREVOKE:
 			{
-				struct hid_device *hid = dev->hid;
-				if (_IOC_TYPE(cmd) != 'H') {
-					ret = -EINVAL;
-					break;
-				}
+				struct hidraw_list *list = file->private_data;
 
-				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCSFEATURE(0))) {
-					int len = _IOC_SIZE(cmd);
-					ret = hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
-					break;
-				}
-				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGFEATURE(0))) {
-					int len = _IOC_SIZE(cmd);
-					ret = hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
-					break;
-				}
+				if (arg)
+					return -EINVAL;
 
-				/* Begin Read-only ioctls. */
-				if (_IOC_DIR(cmd) != _IOC_READ) {
-					ret = -EINVAL;
-					break;
-				}
+				return hidraw_revoke(list);
+			}
+		default:
+			/*
+			 * None of the above ioctls can return -EAGAIN, so
+			 * use it as a marker that we need to check variable
+			 * length ioctls.
+			 */
+			return -EAGAIN;
+	}
 
-				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWNAME(0))) {
-					int len = strlen(hid->name) + 1;
-					if (len > _IOC_SIZE(cmd))
-						len = _IOC_SIZE(cmd);
-					ret = copy_to_user(user_arg, hid->name, len) ?
-						-EFAULT : len;
-					break;
-				}
+	return 0;
+}
 
-				if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGRAWPHYS(0))) {
-					int len = strlen(hid->phys) + 1;
-					if (len > _IOC_SIZE(cmd))
-						len = _IOC_SIZE(cmd);
-					ret = copy_to_user(user_arg, hid->phys, len) ?
-						-EFAULT : len;
-					break;
-				}
-			}
+static long hidraw_rw_variable_size_ioctl(struct file *file, struct hidraw *dev, unsigned int cmd,
+					  void __user *user_arg)
+{
+	int len = _IOC_SIZE(cmd);
+
+	switch (cmd & ~IOCSIZE_MASK) {
+	case HIDIOCSFEATURE(0):
+		return hidraw_send_report(file, user_arg, len, HID_FEATURE_REPORT);
+	case HIDIOCGFEATURE(0):
+		return hidraw_get_report(file, user_arg, len, HID_FEATURE_REPORT);
+	case HIDIOCSINPUT(0):
+		return hidraw_send_report(file, user_arg, len, HID_INPUT_REPORT);
+	case HIDIOCGINPUT(0):
+		return hidraw_get_report(file, user_arg, len, HID_INPUT_REPORT);
+	case HIDIOCSOUTPUT(0):
+		return hidraw_send_report(file, user_arg, len, HID_OUTPUT_REPORT);
+	case HIDIOCGOUTPUT(0):
+		return hidraw_get_report(file, user_arg, len, HID_OUTPUT_REPORT);
+	}
+
+	return -EINVAL;
+}
 
+static long hidraw_ro_variable_size_ioctl(struct file *file, struct hidraw *dev, unsigned int cmd,
+					  void __user *user_arg)
+{
+	struct hid_device *hid = dev->hid;
+	int len = _IOC_SIZE(cmd);
+	int field_len;
+
+	switch (cmd & ~IOCSIZE_MASK) {
+	case HIDIOCGRAWNAME(0):
+		field_len = strlen(hid->name) + 1;
+		if (len > field_len)
+			len = field_len;
+		return copy_to_user(user_arg, hid->name, len) ?  -EFAULT : len;
+	case HIDIOCGRAWPHYS(0):
+		field_len = strlen(hid->phys) + 1;
+		if (len > field_len)
+			len = field_len;
+		return copy_to_user(user_arg, hid->phys, len) ?  -EFAULT : len;
+	case HIDIOCGRAWUNIQ(0):
+		field_len = strlen(hid->uniq) + 1;
+		if (len > field_len)
+			len = field_len;
+		return copy_to_user(user_arg, hid->uniq, len) ?  -EFAULT : len;
+	}
+
+	return -EINVAL;
+}
+
+static long hidraw_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct inode *inode = file_inode(file);
+	unsigned int minor = iminor(inode);
+	struct hidraw *dev;
+	struct hidraw_list *list = file->private_data;
+	void __user *user_arg = (void __user *)arg;
+	int ret;
+
+	down_read(&minors_rwsem);
+	dev = hidraw_table[minor];
+	if (!dev || !dev->exist || hidraw_is_revoked(list)) {
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (_IOC_TYPE(cmd) != 'H') {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (_IOC_NR(cmd) > HIDIOCTL_LAST || _IOC_NR(cmd) == 0) {
 		ret = -ENOTTY;
+		goto out;
+	}
+
+	ret = hidraw_fixed_size_ioctl(file, dev, cmd, user_arg);
+	if (ret != -EAGAIN)
+		goto out;
+
+	switch (_IOC_DIR(cmd)) {
+	case (_IOC_READ | _IOC_WRITE):
+		ret = hidraw_rw_variable_size_ioctl(file, dev, cmd, user_arg);
+		break;
+	case _IOC_READ:
+		ret = hidraw_ro_variable_size_ioctl(file, dev, cmd, user_arg);
+		break;
+	default:
+		/* Any other IOC_DIR is wrong */
+		ret = -EINVAL;
 	}
+
 out:
-	mutex_unlock(&minors_lock);
+	up_read(&minors_rwsem);
 	return ret;
 }
 
@@ -471,9 +563,7 @@ static const struct file_operations hidraw_ops = {
 	.release =      hidraw_release,
 	.unlocked_ioctl = hidraw_ioctl,
 	.fasync =	hidraw_fasync,
-#ifdef CONFIG_COMPAT
-	.compat_ioctl   = hidraw_ioctl,
-#endif
+	.compat_ioctl   = compat_ptr_ioctl,
 	.llseek =	noop_llseek,
 };
 
@@ -488,7 +578,7 @@ int hidraw_report_event(struct hid_device *hid, u8 *data, int len)
 	list_for_each_entry(list, &dev->list, node) {
 		int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
 
-		if (new_head == list->tail)
+		if (hidraw_is_revoked(list) || new_head == list->tail)
 			continue;
 
 		if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) {
@@ -519,7 +609,7 @@ int hidraw_connect(struct hid_device *hid)
 
 	result = -EINVAL;
 
-	mutex_lock(&minors_lock);
+	down_write(&minors_rwsem);
 
 	for (minor = 0; minor < HIDRAW_MAX_DEVICES; minor++) {
 		if (hidraw_table[minor])
@@ -530,17 +620,17 @@ int hidraw_connect(struct hid_device *hid)
 	}
 
 	if (result) {
-		mutex_unlock(&minors_lock);
+		up_write(&minors_rwsem);
 		kfree(dev);
 		goto out;
 	}
 
-	dev->dev = device_create(hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
+	dev->dev = device_create(&hidraw_class, &hid->dev, MKDEV(hidraw_major, minor),
 				 NULL, "%s%d", "hidraw", minor);
 
 	if (IS_ERR(dev->dev)) {
 		hidraw_table[minor] = NULL;
-		mutex_unlock(&minors_lock);
+		up_write(&minors_rwsem);
 		result = PTR_ERR(dev->dev);
 		kfree(dev);
 		goto out;
@@ -556,7 +646,7 @@ int hidraw_connect(struct hid_device *hid)
 	dev->exist = 1;
 	hid->hidraw = dev;
 
-	mutex_unlock(&minors_lock);
+	up_write(&minors_rwsem);
 out:
 	return result;
 
@@ -567,11 +657,11 @@ void hidraw_disconnect(struct hid_device *hid)
 {
 	struct hidraw *hidraw = hid->hidraw;
 
-	mutex_lock(&minors_lock);
+	down_write(&minors_rwsem);
 
 	drop_ref(hidraw, 1);
 
-	mutex_unlock(&minors_lock);
+	up_write(&minors_rwsem);
 }
 EXPORT_SYMBOL_GPL(hidraw_disconnect);
 
@@ -589,23 +679,21 @@ int __init hidraw_init(void)
 
 	hidraw_major = MAJOR(dev_id);
 
-	hidraw_class = class_create(THIS_MODULE, "hidraw");
-	if (IS_ERR(hidraw_class)) {
-		result = PTR_ERR(hidraw_class);
+	result = class_register(&hidraw_class);
+	if (result)
 		goto error_cdev;
-	}
 
         cdev_init(&hidraw_cdev, &hidraw_ops);
 	result = cdev_add(&hidraw_cdev, dev_id, HIDRAW_MAX_DEVICES);
 	if (result < 0)
 		goto error_class;
 
-	printk(KERN_INFO "hidraw: raw HID events driver (C) Jiri Kosina\n");
+	pr_info("raw HID events driver (C) Jiri Kosina\n");
 out:
 	return result;
 
 error_class:
-	class_destroy(hidraw_class);
+	class_unregister(&hidraw_class);
 error_cdev:
 	unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
 	goto out;
@@ -616,7 +704,7 @@ void hidraw_exit(void)
 	dev_t dev_id = MKDEV(hidraw_major, 0);
 
 	cdev_del(&hidraw_cdev);
-	class_destroy(hidraw_class);
+	class_unregister(&hidraw_class);
 	unregister_chrdev_region(dev_id, HIDRAW_MAX_DEVICES);
 
 }