Commit 2f1763f6 authored Mar 03, 2026 by Benoît Sevens Committed by Jiri Kosina Mar 09, 2026

HID: wacom: fix out-of-bounds read in wacom_intuos_bt_irq



The wacom_intuos_bt_irq() function processes Bluetooth HID reports
without sufficient bounds checking. A maliciously crafted short report
can trigger an out-of-bounds read when copying data into the wacom
structure.

Specifically, report 0x03 requires at least 22 bytes to safely read
the processed data and battery status, while report 0x04 (which
falls through to 0x03) requires 32 bytes.

Add explicit length checks for these report IDs and log a warning if
a short report is received.

Signed-off-by: Benoît Sevens <bsevens@google.com>
Reviewed-by: Jason Gerecke <jason.gerecke@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

parent e31b556c

drivers/hid/wacom_wac.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -1208,10 +1208,20 @@ static int wacom_intuos_bt_irq(struct wacom_wac *wacom, size_t len)

		switch (data[0]) {
		case 0x04:
		if (len < 32) {
		dev_warn(wacom->pen_input->dev.parent,
		"Report 0x04 too short: %zu bytes\n", len);
		break;
		}
		wacom_intuos_bt_process_data(wacom, data + i);
		i += 10;
		fallthrough;
		case 0x03:
		if (i == 1 && len < 22) {
		dev_warn(wacom->pen_input->dev.parent,
		"Report 0x03 too short: %zu bytes\n", len);
		break;
		}
		wacom_intuos_bt_process_data(wacom, data + i);
		i += 10;
		wacom_intuos_bt_process_data(wacom, data + i);