From 409353cbe9fe48f6bc196114c442b1cff05a39bc Mon Sep 17 00:00:00 2001 From: Jeff LaBundy Date: Sun, 20 Mar 2022 21:55:27 -0700 Subject: [PATCH] Input: add bounds checking to input_set_capability() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Jeff LaBundy Reviewed-by: Tomasz Moń Link: https://lore.kernel.org/r/20220320032537.545250-1-jeff@labundy.com Signed-off-by: Dmitry Torokhov --- drivers/input/input.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/input/input.c b/drivers/input/input.c index 7c7e4042ec1031..6428cdacf534e5 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -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);