From 0b3f6569a560aa68c9c50cae0e1bc401f7ee699f Mon Sep 17 00:00:00 2001 From: Peter Wu Date: Tue, 16 Dec 2014 16:55:22 +0100 Subject: [PATCH] HID: logitech-hidpp: check WTP report length Malicious USB devices can send bogus reports smaller than the expected buffer size. Ensure that the length for WTP reports is valid to avoid reading out of bounds. Signed-off-by: Peter Wu Reviewed-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-logitech-hidpp.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index 2f420c0..dd3c21b5 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -794,6 +794,11 @@ static int wtp_raw_event(struct hid_device *hdev, u8 *data, int size) switch (data[0]) { case 0x02: + if (size < 2) { + hid_err(hdev, "Received HID report of bad size (%d)", + size); + return 1; + } if (hidpp->quirks & HIDPP_QUIRK_WTP_PHYSICAL_BUTTONS) { input_event(wd->input, EV_KEY, BTN_LEFT, !!(data[1] & 0x01)); @@ -806,6 +811,7 @@ static int wtp_raw_event(struct hid_device *hdev, u8 *data, int size) return wtp_mouse_raw_xy_event(hidpp, &data[7]); } case REPORT_ID_HIDPP_LONG: + /* size is already checked in hidpp_raw_event. */ if ((report->fap.feature_index != wd->mt_feature_index) || (report->fap.funcindex_clientid != EVENT_TOUCHPAD_RAW_XY)) return 1; -- 2.7.4