report_fixup for the Cougar 500k Gaming Keyboard was not verifying that the report descriptor size was correct before accessing it Reported-by: syzbot+24c0361074799d02c452@xxxxxxxxxxxxxxxxxxxxxxxxx Closes: https://syzkaller.appspot.com/bug?extid=24c0361074799d02c452 Signed-off-by: Camila Alvarez <cam.alvarez.i@xxxxxxxxx> --- drivers/hid/hid-cougar.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hid-cougar.c b/drivers/hid/hid-cougar.c index cb8bd8aae15b..0fa785f52707 100644 --- a/drivers/hid/hid-cougar.c +++ b/drivers/hid/hid-cougar.c @@ -106,7 +106,7 @@ static void cougar_fix_g6_mapping(void) static __u8 *cougar_report_fixup(struct hid_device *hdev, __u8 *rdesc, unsigned int *rsize) { - if (rdesc[2] == 0x09 && rdesc[3] == 0x02 && + if (*rsize >= 117 && rdesc[2] == 0x09 && rdesc[3] == 0x02 && (rdesc[115] | rdesc[116] << 8) >= HID_MAX_USAGES) { hid_info(hdev, "usage count exceeds max: fixing up report descriptor\n"); -- 2.34.1