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800 lines
18 KiB
800 lines
18 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* User-space I/O driver support for HID subsystem |
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* Copyright (c) 2012 David Herrmann |
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*/ |
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|
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/* |
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*/ |
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#include <linux/atomic.h> |
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#include <linux/compat.h> |
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#include <linux/cred.h> |
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#include <linux/device.h> |
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#include <linux/fs.h> |
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#include <linux/hid.h> |
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#include <linux/input.h> |
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#include <linux/miscdevice.h> |
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#include <linux/module.h> |
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#include <linux/mutex.h> |
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#include <linux/poll.h> |
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#include <linux/sched.h> |
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#include <linux/spinlock.h> |
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#include <linux/uhid.h> |
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#include <linux/wait.h> |
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#define UHID_NAME "uhid" |
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#define UHID_BUFSIZE 32 |
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struct uhid_device { |
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struct mutex devlock; |
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bool running; |
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__u8 *rd_data; |
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uint rd_size; |
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struct hid_device *hid; |
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struct uhid_event input_buf; |
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wait_queue_head_t waitq; |
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spinlock_t qlock; |
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__u8 head; |
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__u8 tail; |
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struct uhid_event *outq[UHID_BUFSIZE]; |
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/* blocking GET_REPORT support; state changes protected by qlock */ |
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struct mutex report_lock; |
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wait_queue_head_t report_wait; |
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bool report_running; |
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u32 report_id; |
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u32 report_type; |
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struct uhid_event report_buf; |
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struct work_struct worker; |
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}; |
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static struct miscdevice uhid_misc; |
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static void uhid_device_add_worker(struct work_struct *work) |
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{ |
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struct uhid_device *uhid = container_of(work, struct uhid_device, worker); |
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int ret; |
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ret = hid_add_device(uhid->hid); |
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if (ret) { |
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hid_err(uhid->hid, "Cannot register HID device: error %d\n", ret); |
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hid_destroy_device(uhid->hid); |
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uhid->hid = NULL; |
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uhid->running = false; |
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} |
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} |
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static void uhid_queue(struct uhid_device *uhid, struct uhid_event *ev) |
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{ |
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__u8 newhead; |
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newhead = (uhid->head + 1) % UHID_BUFSIZE; |
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if (newhead != uhid->tail) { |
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uhid->outq[uhid->head] = ev; |
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uhid->head = newhead; |
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wake_up_interruptible(&uhid->waitq); |
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} else { |
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hid_warn(uhid->hid, "Output queue is full\n"); |
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kfree(ev); |
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} |
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} |
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static int uhid_queue_event(struct uhid_device *uhid, __u32 event) |
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{ |
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unsigned long flags; |
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struct uhid_event *ev; |
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ev = kzalloc(sizeof(*ev), GFP_KERNEL); |
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if (!ev) |
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return -ENOMEM; |
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ev->type = event; |
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spin_lock_irqsave(&uhid->qlock, flags); |
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uhid_queue(uhid, ev); |
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spin_unlock_irqrestore(&uhid->qlock, flags); |
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return 0; |
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} |
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static int uhid_hid_start(struct hid_device *hid) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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struct uhid_event *ev; |
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unsigned long flags; |
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ev = kzalloc(sizeof(*ev), GFP_KERNEL); |
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if (!ev) |
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return -ENOMEM; |
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ev->type = UHID_START; |
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if (hid->report_enum[HID_FEATURE_REPORT].numbered) |
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ev->u.start.dev_flags |= UHID_DEV_NUMBERED_FEATURE_REPORTS; |
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if (hid->report_enum[HID_OUTPUT_REPORT].numbered) |
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ev->u.start.dev_flags |= UHID_DEV_NUMBERED_OUTPUT_REPORTS; |
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if (hid->report_enum[HID_INPUT_REPORT].numbered) |
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ev->u.start.dev_flags |= UHID_DEV_NUMBERED_INPUT_REPORTS; |
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spin_lock_irqsave(&uhid->qlock, flags); |
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uhid_queue(uhid, ev); |
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spin_unlock_irqrestore(&uhid->qlock, flags); |
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return 0; |
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} |
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static void uhid_hid_stop(struct hid_device *hid) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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hid->claimed = 0; |
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uhid_queue_event(uhid, UHID_STOP); |
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} |
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static int uhid_hid_open(struct hid_device *hid) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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return uhid_queue_event(uhid, UHID_OPEN); |
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} |
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static void uhid_hid_close(struct hid_device *hid) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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uhid_queue_event(uhid, UHID_CLOSE); |
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} |
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static int uhid_hid_parse(struct hid_device *hid) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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return hid_parse_report(hid, uhid->rd_data, uhid->rd_size); |
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} |
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/* must be called with report_lock held */ |
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static int __uhid_report_queue_and_wait(struct uhid_device *uhid, |
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struct uhid_event *ev, |
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__u32 *report_id) |
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{ |
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unsigned long flags; |
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int ret; |
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spin_lock_irqsave(&uhid->qlock, flags); |
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*report_id = ++uhid->report_id; |
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uhid->report_type = ev->type + 1; |
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uhid->report_running = true; |
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uhid_queue(uhid, ev); |
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spin_unlock_irqrestore(&uhid->qlock, flags); |
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ret = wait_event_interruptible_timeout(uhid->report_wait, |
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!uhid->report_running || !uhid->running, |
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5 * HZ); |
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if (!ret || !uhid->running || uhid->report_running) |
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ret = -EIO; |
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else if (ret < 0) |
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ret = -ERESTARTSYS; |
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else |
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ret = 0; |
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uhid->report_running = false; |
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return ret; |
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} |
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static void uhid_report_wake_up(struct uhid_device *uhid, u32 id, |
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const struct uhid_event *ev) |
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{ |
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unsigned long flags; |
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spin_lock_irqsave(&uhid->qlock, flags); |
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/* id for old report; drop it silently */ |
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if (uhid->report_type != ev->type || uhid->report_id != id) |
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goto unlock; |
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if (!uhid->report_running) |
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goto unlock; |
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memcpy(&uhid->report_buf, ev, sizeof(*ev)); |
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uhid->report_running = false; |
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wake_up_interruptible(&uhid->report_wait); |
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unlock: |
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spin_unlock_irqrestore(&uhid->qlock, flags); |
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} |
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static int uhid_hid_get_report(struct hid_device *hid, unsigned char rnum, |
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u8 *buf, size_t count, u8 rtype) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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struct uhid_get_report_reply_req *req; |
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struct uhid_event *ev; |
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int ret; |
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if (!uhid->running) |
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return -EIO; |
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ev = kzalloc(sizeof(*ev), GFP_KERNEL); |
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if (!ev) |
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return -ENOMEM; |
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ev->type = UHID_GET_REPORT; |
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ev->u.get_report.rnum = rnum; |
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ev->u.get_report.rtype = rtype; |
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ret = mutex_lock_interruptible(&uhid->report_lock); |
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if (ret) { |
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kfree(ev); |
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return ret; |
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} |
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/* this _always_ takes ownership of @ev */ |
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ret = __uhid_report_queue_and_wait(uhid, ev, &ev->u.get_report.id); |
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if (ret) |
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goto unlock; |
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req = &uhid->report_buf.u.get_report_reply; |
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if (req->err) { |
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ret = -EIO; |
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} else { |
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ret = min3(count, (size_t)req->size, (size_t)UHID_DATA_MAX); |
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memcpy(buf, req->data, ret); |
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} |
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unlock: |
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mutex_unlock(&uhid->report_lock); |
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return ret; |
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} |
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static int uhid_hid_set_report(struct hid_device *hid, unsigned char rnum, |
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const u8 *buf, size_t count, u8 rtype) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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struct uhid_event *ev; |
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int ret; |
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if (!uhid->running || count > UHID_DATA_MAX) |
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return -EIO; |
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ev = kzalloc(sizeof(*ev), GFP_KERNEL); |
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if (!ev) |
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return -ENOMEM; |
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ev->type = UHID_SET_REPORT; |
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ev->u.set_report.rnum = rnum; |
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ev->u.set_report.rtype = rtype; |
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ev->u.set_report.size = count; |
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memcpy(ev->u.set_report.data, buf, count); |
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ret = mutex_lock_interruptible(&uhid->report_lock); |
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if (ret) { |
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kfree(ev); |
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return ret; |
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} |
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/* this _always_ takes ownership of @ev */ |
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ret = __uhid_report_queue_and_wait(uhid, ev, &ev->u.set_report.id); |
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if (ret) |
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goto unlock; |
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if (uhid->report_buf.u.set_report_reply.err) |
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ret = -EIO; |
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else |
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ret = count; |
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unlock: |
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mutex_unlock(&uhid->report_lock); |
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return ret; |
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} |
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static int uhid_hid_raw_request(struct hid_device *hid, unsigned char reportnum, |
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__u8 *buf, size_t len, unsigned char rtype, |
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int reqtype) |
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{ |
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u8 u_rtype; |
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switch (rtype) { |
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case HID_FEATURE_REPORT: |
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u_rtype = UHID_FEATURE_REPORT; |
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break; |
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case HID_OUTPUT_REPORT: |
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u_rtype = UHID_OUTPUT_REPORT; |
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break; |
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case HID_INPUT_REPORT: |
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u_rtype = UHID_INPUT_REPORT; |
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break; |
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default: |
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return -EINVAL; |
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} |
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switch (reqtype) { |
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case HID_REQ_GET_REPORT: |
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return uhid_hid_get_report(hid, reportnum, buf, len, u_rtype); |
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case HID_REQ_SET_REPORT: |
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return uhid_hid_set_report(hid, reportnum, buf, len, u_rtype); |
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default: |
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return -EIO; |
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} |
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} |
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static int uhid_hid_output_raw(struct hid_device *hid, __u8 *buf, size_t count, |
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unsigned char report_type) |
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{ |
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struct uhid_device *uhid = hid->driver_data; |
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__u8 rtype; |
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unsigned long flags; |
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struct uhid_event *ev; |
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switch (report_type) { |
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case HID_FEATURE_REPORT: |
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rtype = UHID_FEATURE_REPORT; |
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break; |
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case HID_OUTPUT_REPORT: |
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rtype = UHID_OUTPUT_REPORT; |
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break; |
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default: |
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return -EINVAL; |
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} |
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if (count < 1 || count > UHID_DATA_MAX) |
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return -EINVAL; |
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ev = kzalloc(sizeof(*ev), GFP_KERNEL); |
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if (!ev) |
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return -ENOMEM; |
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ev->type = UHID_OUTPUT; |
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ev->u.output.size = count; |
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ev->u.output.rtype = rtype; |
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memcpy(ev->u.output.data, buf, count); |
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spin_lock_irqsave(&uhid->qlock, flags); |
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uhid_queue(uhid, ev); |
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spin_unlock_irqrestore(&uhid->qlock, flags); |
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return count; |
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} |
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static int uhid_hid_output_report(struct hid_device *hid, __u8 *buf, |
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size_t count) |
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{ |
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return uhid_hid_output_raw(hid, buf, count, HID_OUTPUT_REPORT); |
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} |
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struct hid_ll_driver uhid_hid_driver = { |
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.start = uhid_hid_start, |
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.stop = uhid_hid_stop, |
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.open = uhid_hid_open, |
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.close = uhid_hid_close, |
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.parse = uhid_hid_parse, |
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.raw_request = uhid_hid_raw_request, |
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.output_report = uhid_hid_output_report, |
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}; |
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EXPORT_SYMBOL_GPL(uhid_hid_driver); |
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#ifdef CONFIG_COMPAT |
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/* Apparently we haven't stepped on these rakes enough times yet. */ |
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struct uhid_create_req_compat { |
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__u8 name[128]; |
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__u8 phys[64]; |
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__u8 uniq[64]; |
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compat_uptr_t rd_data; |
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__u16 rd_size; |
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__u16 bus; |
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__u32 vendor; |
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__u32 product; |
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__u32 version; |
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__u32 country; |
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} __attribute__((__packed__)); |
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static int uhid_event_from_user(const char __user *buffer, size_t len, |
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struct uhid_event *event) |
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{ |
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if (in_compat_syscall()) { |
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u32 type; |
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if (get_user(type, buffer)) |
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return -EFAULT; |
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if (type == UHID_CREATE) { |
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/* |
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* This is our messed up request with compat pointer. |
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* It is largish (more than 256 bytes) so we better |
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* allocate it from the heap. |
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*/ |
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struct uhid_create_req_compat *compat; |
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compat = kzalloc(sizeof(*compat), GFP_KERNEL); |
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if (!compat) |
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return -ENOMEM; |
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buffer += sizeof(type); |
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len -= sizeof(type); |
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if (copy_from_user(compat, buffer, |
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min(len, sizeof(*compat)))) { |
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kfree(compat); |
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return -EFAULT; |
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} |
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/* Shuffle the data over to proper structure */ |
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event->type = type; |
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memcpy(event->u.create.name, compat->name, |
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sizeof(compat->name)); |
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memcpy(event->u.create.phys, compat->phys, |
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sizeof(compat->phys)); |
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memcpy(event->u.create.uniq, compat->uniq, |
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sizeof(compat->uniq)); |
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event->u.create.rd_data = compat_ptr(compat->rd_data); |
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event->u.create.rd_size = compat->rd_size; |
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event->u.create.bus = compat->bus; |
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event->u.create.vendor = compat->vendor; |
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event->u.create.product = compat->product; |
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event->u.create.version = compat->version; |
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event->u.create.country = compat->country; |
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kfree(compat); |
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return 0; |
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} |
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/* All others can be copied directly */ |
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} |
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if (copy_from_user(event, buffer, min(len, sizeof(*event)))) |
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return -EFAULT; |
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return 0; |
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} |
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#else |
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static int uhid_event_from_user(const char __user *buffer, size_t len, |
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struct uhid_event *event) |
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{ |
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if (copy_from_user(event, buffer, min(len, sizeof(*event)))) |
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return -EFAULT; |
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return 0; |
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} |
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#endif |
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static int uhid_dev_create2(struct uhid_device *uhid, |
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const struct uhid_event *ev) |
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{ |
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struct hid_device *hid; |
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size_t rd_size, len; |
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void *rd_data; |
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int ret; |
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if (uhid->running) |
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return -EALREADY; |
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rd_size = ev->u.create2.rd_size; |
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if (rd_size <= 0 || rd_size > HID_MAX_DESCRIPTOR_SIZE) |
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return -EINVAL; |
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rd_data = kmemdup(ev->u.create2.rd_data, rd_size, GFP_KERNEL); |
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if (!rd_data) |
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return -ENOMEM; |
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uhid->rd_size = rd_size; |
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uhid->rd_data = rd_data; |
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hid = hid_allocate_device(); |
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if (IS_ERR(hid)) { |
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ret = PTR_ERR(hid); |
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goto err_free; |
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} |
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/* @hid is zero-initialized, strncpy() is correct, strlcpy() not */ |
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len = min(sizeof(hid->name), sizeof(ev->u.create2.name)) - 1; |
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strncpy(hid->name, ev->u.create2.name, len); |
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len = min(sizeof(hid->phys), sizeof(ev->u.create2.phys)) - 1; |
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strncpy(hid->phys, ev->u.create2.phys, len); |
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len = min(sizeof(hid->uniq), sizeof(ev->u.create2.uniq)) - 1; |
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strncpy(hid->uniq, ev->u.create2.uniq, len); |
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hid->ll_driver = &uhid_hid_driver; |
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hid->bus = ev->u.create2.bus; |
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hid->vendor = ev->u.create2.vendor; |
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hid->product = ev->u.create2.product; |
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hid->version = ev->u.create2.version; |
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hid->country = ev->u.create2.country; |
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hid->driver_data = uhid; |
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hid->dev.parent = uhid_misc.this_device; |
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uhid->hid = hid; |
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uhid->running = true; |
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/* Adding of a HID device is done through a worker, to allow HID drivers |
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* which use feature requests during .probe to work, without they would |
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* be blocked on devlock, which is held by uhid_char_write. |
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*/ |
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schedule_work(&uhid->worker); |
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return 0; |
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err_free: |
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kfree(uhid->rd_data); |
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uhid->rd_data = NULL; |
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uhid->rd_size = 0; |
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return ret; |
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} |
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static int uhid_dev_create(struct uhid_device *uhid, |
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struct uhid_event *ev) |
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{ |
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struct uhid_create_req orig; |
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orig = ev->u.create; |
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if (orig.rd_size <= 0 || orig.rd_size > HID_MAX_DESCRIPTOR_SIZE) |
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return -EINVAL; |
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if (copy_from_user(&ev->u.create2.rd_data, orig.rd_data, orig.rd_size)) |
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return -EFAULT; |
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memcpy(ev->u.create2.name, orig.name, sizeof(orig.name)); |
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memcpy(ev->u.create2.phys, orig.phys, sizeof(orig.phys)); |
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memcpy(ev->u.create2.uniq, orig.uniq, sizeof(orig.uniq)); |
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ev->u.create2.rd_size = orig.rd_size; |
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ev->u.create2.bus = orig.bus; |
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ev->u.create2.vendor = orig.vendor; |
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ev->u.create2.product = orig.product; |
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ev->u.create2.version = orig.version; |
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ev->u.create2.country = orig.country; |
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return uhid_dev_create2(uhid, ev); |
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} |
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static int uhid_dev_destroy(struct uhid_device *uhid) |
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{ |
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if (!uhid->running) |
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return -EINVAL; |
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uhid->running = false; |
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wake_up_interruptible(&uhid->report_wait); |
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cancel_work_sync(&uhid->worker); |
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hid_destroy_device(uhid->hid); |
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kfree(uhid->rd_data); |
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return 0; |
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} |
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static int uhid_dev_input(struct uhid_device *uhid, struct uhid_event *ev) |
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{ |
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if (!uhid->running) |
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return -EINVAL; |
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hid_input_report(uhid->hid, HID_INPUT_REPORT, ev->u.input.data, |
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min_t(size_t, ev->u.input.size, UHID_DATA_MAX), 0); |
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return 0; |
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} |
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static int uhid_dev_input2(struct uhid_device *uhid, struct uhid_event *ev) |
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{ |
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if (!uhid->running) |
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return -EINVAL; |
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hid_input_report(uhid->hid, HID_INPUT_REPORT, ev->u.input2.data, |
|
min_t(size_t, ev->u.input2.size, UHID_DATA_MAX), 0); |
|
|
|
return 0; |
|
} |
|
|
|
static int uhid_dev_get_report_reply(struct uhid_device *uhid, |
|
struct uhid_event *ev) |
|
{ |
|
if (!uhid->running) |
|
return -EINVAL; |
|
|
|
uhid_report_wake_up(uhid, ev->u.get_report_reply.id, ev); |
|
return 0; |
|
} |
|
|
|
static int uhid_dev_set_report_reply(struct uhid_device *uhid, |
|
struct uhid_event *ev) |
|
{ |
|
if (!uhid->running) |
|
return -EINVAL; |
|
|
|
uhid_report_wake_up(uhid, ev->u.set_report_reply.id, ev); |
|
return 0; |
|
} |
|
|
|
static int uhid_char_open(struct inode *inode, struct file *file) |
|
{ |
|
struct uhid_device *uhid; |
|
|
|
uhid = kzalloc(sizeof(*uhid), GFP_KERNEL); |
|
if (!uhid) |
|
return -ENOMEM; |
|
|
|
mutex_init(&uhid->devlock); |
|
mutex_init(&uhid->report_lock); |
|
spin_lock_init(&uhid->qlock); |
|
init_waitqueue_head(&uhid->waitq); |
|
init_waitqueue_head(&uhid->report_wait); |
|
uhid->running = false; |
|
INIT_WORK(&uhid->worker, uhid_device_add_worker); |
|
|
|
file->private_data = uhid; |
|
stream_open(inode, file); |
|
|
|
return 0; |
|
} |
|
|
|
static int uhid_char_release(struct inode *inode, struct file *file) |
|
{ |
|
struct uhid_device *uhid = file->private_data; |
|
unsigned int i; |
|
|
|
uhid_dev_destroy(uhid); |
|
|
|
for (i = 0; i < UHID_BUFSIZE; ++i) |
|
kfree(uhid->outq[i]); |
|
|
|
kfree(uhid); |
|
|
|
return 0; |
|
} |
|
|
|
static ssize_t uhid_char_read(struct file *file, char __user *buffer, |
|
size_t count, loff_t *ppos) |
|
{ |
|
struct uhid_device *uhid = file->private_data; |
|
int ret; |
|
unsigned long flags; |
|
size_t len; |
|
|
|
/* they need at least the "type" member of uhid_event */ |
|
if (count < sizeof(__u32)) |
|
return -EINVAL; |
|
|
|
try_again: |
|
if (file->f_flags & O_NONBLOCK) { |
|
if (uhid->head == uhid->tail) |
|
return -EAGAIN; |
|
} else { |
|
ret = wait_event_interruptible(uhid->waitq, |
|
uhid->head != uhid->tail); |
|
if (ret) |
|
return ret; |
|
} |
|
|
|
ret = mutex_lock_interruptible(&uhid->devlock); |
|
if (ret) |
|
return ret; |
|
|
|
if (uhid->head == uhid->tail) { |
|
mutex_unlock(&uhid->devlock); |
|
goto try_again; |
|
} else { |
|
len = min(count, sizeof(**uhid->outq)); |
|
if (copy_to_user(buffer, uhid->outq[uhid->tail], len)) { |
|
ret = -EFAULT; |
|
} else { |
|
kfree(uhid->outq[uhid->tail]); |
|
uhid->outq[uhid->tail] = NULL; |
|
|
|
spin_lock_irqsave(&uhid->qlock, flags); |
|
uhid->tail = (uhid->tail + 1) % UHID_BUFSIZE; |
|
spin_unlock_irqrestore(&uhid->qlock, flags); |
|
} |
|
} |
|
|
|
mutex_unlock(&uhid->devlock); |
|
return ret ? ret : len; |
|
} |
|
|
|
static ssize_t uhid_char_write(struct file *file, const char __user *buffer, |
|
size_t count, loff_t *ppos) |
|
{ |
|
struct uhid_device *uhid = file->private_data; |
|
int ret; |
|
size_t len; |
|
|
|
/* we need at least the "type" member of uhid_event */ |
|
if (count < sizeof(__u32)) |
|
return -EINVAL; |
|
|
|
ret = mutex_lock_interruptible(&uhid->devlock); |
|
if (ret) |
|
return ret; |
|
|
|
memset(&uhid->input_buf, 0, sizeof(uhid->input_buf)); |
|
len = min(count, sizeof(uhid->input_buf)); |
|
|
|
ret = uhid_event_from_user(buffer, len, &uhid->input_buf); |
|
if (ret) |
|
goto unlock; |
|
|
|
switch (uhid->input_buf.type) { |
|
case UHID_CREATE: |
|
/* |
|
* 'struct uhid_create_req' contains a __user pointer which is |
|
* copied from, so it's unsafe to allow this with elevated |
|
* privileges (e.g. from a setuid binary) or via kernel_write(). |
|
*/ |
|
if (file->f_cred != current_cred() || uaccess_kernel()) { |
|
pr_err_once("UHID_CREATE from different security context by process %d (%s), this is not allowed.\n", |
|
task_tgid_vnr(current), current->comm); |
|
ret = -EACCES; |
|
goto unlock; |
|
} |
|
ret = uhid_dev_create(uhid, &uhid->input_buf); |
|
break; |
|
case UHID_CREATE2: |
|
ret = uhid_dev_create2(uhid, &uhid->input_buf); |
|
break; |
|
case UHID_DESTROY: |
|
ret = uhid_dev_destroy(uhid); |
|
break; |
|
case UHID_INPUT: |
|
ret = uhid_dev_input(uhid, &uhid->input_buf); |
|
break; |
|
case UHID_INPUT2: |
|
ret = uhid_dev_input2(uhid, &uhid->input_buf); |
|
break; |
|
case UHID_GET_REPORT_REPLY: |
|
ret = uhid_dev_get_report_reply(uhid, &uhid->input_buf); |
|
break; |
|
case UHID_SET_REPORT_REPLY: |
|
ret = uhid_dev_set_report_reply(uhid, &uhid->input_buf); |
|
break; |
|
default: |
|
ret = -EOPNOTSUPP; |
|
} |
|
|
|
unlock: |
|
mutex_unlock(&uhid->devlock); |
|
|
|
/* return "count" not "len" to not confuse the caller */ |
|
return ret ? ret : count; |
|
} |
|
|
|
static __poll_t uhid_char_poll(struct file *file, poll_table *wait) |
|
{ |
|
struct uhid_device *uhid = file->private_data; |
|
__poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uhid is always writable */ |
|
|
|
poll_wait(file, &uhid->waitq, wait); |
|
|
|
if (uhid->head != uhid->tail) |
|
mask |= EPOLLIN | EPOLLRDNORM; |
|
|
|
return mask; |
|
} |
|
|
|
static const struct file_operations uhid_fops = { |
|
.owner = THIS_MODULE, |
|
.open = uhid_char_open, |
|
.release = uhid_char_release, |
|
.read = uhid_char_read, |
|
.write = uhid_char_write, |
|
.poll = uhid_char_poll, |
|
.llseek = no_llseek, |
|
}; |
|
|
|
static struct miscdevice uhid_misc = { |
|
.fops = &uhid_fops, |
|
.minor = UHID_MINOR, |
|
.name = UHID_NAME, |
|
}; |
|
module_misc_device(uhid_misc); |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_AUTHOR("David Herrmann <[email protected]>"); |
|
MODULE_DESCRIPTION("User-space I/O driver support for HID subsystem"); |
|
MODULE_ALIAS_MISCDEV(UHID_MINOR); |
|
MODULE_ALIAS("devname:" UHID_NAME);
|
|
|