Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751618AbaLPV4H (ORCPT ); Tue, 16 Dec 2014 16:56:07 -0500 Received: from mail-qg0-f46.google.com ([209.85.192.46]:63350 "EHLO mail-qg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751429AbaLPV4F (ORCPT ); Tue, 16 Dec 2014 16:56:05 -0500 MIME-Version: 1.0 In-Reply-To: <1418745323-17133-2-git-send-email-peter@lekensteyn.nl> References: <1418745323-17133-1-git-send-email-peter@lekensteyn.nl> <1418745323-17133-2-git-send-email-peter@lekensteyn.nl> Date: Tue, 16 Dec 2014 16:56:03 -0500 Message-ID: Subject: Re: [PATCH v2 2/3] HID: logitech-hidpp: check WTP report length From: Benjamin Tissoires To: Peter Wu Cc: Jiri Kosina , Benjamin Tissoires , Nestor Lopez Casado , linux-input , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 16, 2014 at 10:55 AM, Peter Wu wrote: > 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 > --- Reviewed-by: Benjamin Tissoires Cheers, Benjamin > 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-input" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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/