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| author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2014-10-06 10:55:49 -0700 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2014-10-07 09:55:01 -0700 |
| commit | 7c4f56070fde2367766fa1fb04852599b5e1ad35 (patch) | |
| tree | bae58fba448d8f38252bc2d7bccffb03fa503a1d /drivers/input/evdev.c | |
| parent | 042e1c79166b9250edd8262bea84e1703f27ad2e (diff) | |
| download | linux-7c4f56070fde2367766fa1fb04852599b5e1ad35.tar.bz2 | |
Input: evdev - fix EVIOCG{type} ioctl
The 'max' size passed into the function is measured in number of bits
(KEY_MAX, LED_MAX, etc) so we need to convert it accordingly before trying
to copy the data out, otherwise we will try copying too much and end up
with up with a page fault.
Reported-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input/evdev.c')
| -rw-r--r-- | drivers/input/evdev.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c index de055451d1af..bc203485716d 100644 --- a/drivers/input/evdev.c +++ b/drivers/input/evdev.c @@ -738,20 +738,23 @@ static int evdev_handle_set_keycode_v2(struct input_dev *dev, void __user *p) */ static int evdev_handle_get_val(struct evdev_client *client, struct input_dev *dev, unsigned int type, - unsigned long *bits, unsigned int max, - unsigned int size, void __user *p, int compat) + unsigned long *bits, unsigned int maxbit, + unsigned int maxlen, void __user *p, + int compat) { int ret; unsigned long *mem; + size_t len; - mem = kmalloc(sizeof(unsigned long) * max, GFP_KERNEL); + len = BITS_TO_LONGS(maxbit) * sizeof(unsigned long); + mem = kmalloc(len, GFP_KERNEL); if (!mem) return -ENOMEM; spin_lock_irq(&dev->event_lock); spin_lock(&client->buffer_lock); - memcpy(mem, bits, sizeof(unsigned long) * max); + memcpy(mem, bits, len); spin_unlock(&dev->event_lock); @@ -759,7 +762,7 @@ static int evdev_handle_get_val(struct evdev_client *client, spin_unlock_irq(&client->buffer_lock); - ret = bits_to_user(mem, max, size, p, compat); + ret = bits_to_user(mem, maxbit, maxlen, p, compat); if (ret < 0) evdev_queue_syn_dropped(client); |