Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751317AbaLPPzk (ORCPT ); Tue, 16 Dec 2014 10:55:40 -0500 Received: from lekensteyn.nl ([178.21.112.251]:59917 "EHLO lekensteyn.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750979AbaLPPzi (ORCPT ); Tue, 16 Dec 2014 10:55:38 -0500 From: Peter Wu To: Jiri Kosina , Benjamin Tissoires Cc: Nestor Lopez Casado , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/3] HID: logitech-hidpp: check WTP report length Date: Tue, 16 Dec 2014 16:55:22 +0100 Message-Id: <1418745323-17133-2-git-send-email-peter@lekensteyn.nl> X-Mailer: git-send-email 2.1.3 In-Reply-To: <1418745323-17133-1-git-send-email-peter@lekensteyn.nl> References: <1418745323-17133-1-git-send-email-peter@lekensteyn.nl> X-Spam-Score: 0.0 (/) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- v1: patch 2/3 HID: logitech-{dj,hidpp}: check report length v2: splitted original report length check patch --- 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 b32f751..2f1b0ac 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -805,6 +805,11 @@ 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)); @@ -818,6 +823,7 @@ 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; -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/