diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index d2b34fbbc42e..b6ded17b3be3 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -48,6 +48,7 @@ struct evdev_client { struct evdev *evdev; struct list_head node; int clkid; + bool revoked; unsigned int bufsize; struct input_event buffer[]; }; @@ -164,6 +165,9 @@ static void evdev_pass_values(struct evdev_client *client, struct input_event event; bool wakeup = false; + if (client->revoked) + return; + event.time = ktime_to_timeval(client->clkid == CLOCK_MONOTONIC ? mono : real); @@ -240,7 +244,7 @@ static int evdev_flush(struct file *file, fl_owner_t id) if (retval) return retval; - if (!evdev->exist) + if (!evdev->exist || client->revoked) retval = -ENODEV; else retval = input_flush_device(&evdev->handle, file); @@ -429,7 +433,7 @@ static ssize_t evdev_write(struct file *file, const char __user *buffer, if (retval) return retval; - if (!evdev->exist) { + if (!evdev->exist || client->revoked) { retval = -ENODEV; goto out; } @@ -482,7 +486,7 @@ static ssize_t evdev_read(struct file *file, char __user *buffer, return -EINVAL; for (;;) { - if (!evdev->exist) + if (!evdev->exist || client->revoked) return -ENODEV; if (client->packet_head == client->tail && @@ -511,7 +515,7 @@ static ssize_t evdev_read(struct file *file, char __user *buffer, if (!(file->f_flags & O_NONBLOCK)) { error = wait_event_interruptible(evdev->wait, client->packet_head != client->tail || - !evdev->exist); + !evdev->exist || client->revoked); if (error) return error; } @@ -529,7 +533,11 @@ static unsigned int evdev_poll(struct file *file, poll_table *wait) poll_wait(file, &evdev->wait, wait); - mask = evdev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR; + if (evdev->exist && !client->revoked) + mask = POLLOUT | POLLWRNORM; + else + mask = POLLHUP | POLLERR; + if (client->packet_head != client->tail) mask |= POLLIN | POLLRDNORM; @@ -795,6 +803,17 @@ static int evdev_handle_mt_request(struct input_dev *dev, return 0; } +static int evdev_revoke(struct evdev *evdev, struct evdev_client *client, + struct file *file) +{ + client->revoked = true; + evdev_ungrab(evdev, client); + input_flush_device(&evdev->handle, file); + wake_up_interruptible(&evdev->wait); + + return 0; +} + static long evdev_do_ioctl(struct file *file, unsigned int cmd, void __user *p, int compat_mode) { @@ -857,6 +876,12 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd, else return evdev_ungrab(evdev, client); + case EVIOCREVOKE: + if (p) + return -EINVAL; + else + return evdev_revoke(evdev, client, file); + case EVIOCSCLOCKID: if (copy_from_user(&i, p, sizeof(unsigned int))) return -EFAULT; @@ -1002,7 +1027,7 @@ static long evdev_ioctl_handler(struct file *file, unsigned int cmd, if (retval) return retval; - if (!evdev->exist) { + if (!evdev->exist || client->revoked) { retval = -ENODEV; goto out; } diff --git a/include/uapi/linux/input.h b/include/uapi/linux/input.h index d08abf9101d2..a3726275876d 100644 --- a/include/uapi/linux/input.h +++ b/include/uapi/linux/input.h @@ -152,6 +152,7 @@ struct input_keymap_entry { #define EVIOCGEFFECTS _IOR('E', 0x84, int) /* Report number of effects playable at the same time */ #define EVIOCGRAB _IOW('E', 0x90, int) /* Grab/Release device */ +#define EVIOCREVOKE _IOW('E', 0x91, int) /* Revoke device access */ #define EVIOCSCLOCKID _IOW('E', 0xa0, int) /* Set clockid to be used for timestamps */