openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

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>
This commit is contained in:
Dmitry Torokhov 2014-10-06 10:55:49 -07:00
parent 042e1c7916
commit 7c4f56070f
1 changed files with 8 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/input/evdev.c
View File

@ -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);