Input: add bounds checking to input_set_capability()

Update input_set_capability() to prevent kernel panic in case the
event code exceeds the bitmap for the given event type.

Suggested-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Reviewed-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220320032537.545250-1-jeff@labundy.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Jeff LaBundy 2022-03-20 21:55:27 -07:00 committed by Dmitry Torokhov
parent 07fc21b486
commit 409353cbe9
1 changed files with 19 additions and 0 deletions

View File

@ -47,6 +47,17 @@ static DEFINE_MUTEX(input_mutex);
static const struct input_value input_value_sync = { EV_SYN, SYN_REPORT, 1 };
static const unsigned int input_max_code[EV_CNT] = {
[EV_KEY] = KEY_MAX,
[EV_REL] = REL_MAX,
[EV_ABS] = ABS_MAX,
[EV_MSC] = MSC_MAX,
[EV_SW] = SW_MAX,
[EV_LED] = LED_MAX,
[EV_SND] = SND_MAX,
[EV_FF] = FF_MAX,
};
static inline int is_event_supported(unsigned int code,
unsigned long *bm, unsigned int max)
{
@ -2110,6 +2121,14 @@ EXPORT_SYMBOL(input_get_timestamp);
*/
void input_set_capability(struct input_dev *dev, unsigned int type, unsigned int code)
{
if (type < EV_CNT && input_max_code[type] &&
code > input_max_code[type]) {
pr_err("%s: invalid code %u for type %u\n", __func__, code,
type);
dump_stack();
return;
}
switch (type) {
case EV_KEY:
__set_bit(code, dev->keybit);