From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755052AbaH0INS (ORCPT ); Wed, 27 Aug 2014 04:13:18 -0400 Received: from smtprelay.restena.lu ([158.64.1.62]:43713 "EHLO smtprelay.restena.lu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751871AbaH0INP convert rfc822-to-8bit (ORCPT ); Wed, 27 Aug 2014 04:13:15 -0400 Date: Wed, 27 Aug 2014 10:13:11 +0200 From: Bruno =?UTF-8?B?UHLDqW1vbnQ=?= To: Jiri Kosina Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] HID: picolcd: sanity check report size in raw_event() callback Message-ID: <20140827101311.098f3fd1@pluto> In-Reply-To: References: X-Mailer: Claws Mail 3.9.0 (GTK+ 2.24.24; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 27 Aug 2014 09:13:15 +0200 (CEST) Jiri Kosina wrote: > The report passed to us from transport driver could potentially be > arbitrarily large, therefore we better sanity-check it so that raw_data > that we hold in picolcd_pending structure are always kept within proper > bounds. > > Cc: stable@vger.kernel.org > Reported-by: Steven Vittitoe > Signed-off-by: Jiri Kosina Acked-by: Bruno Prémont > --- > drivers/hid/hid-picolcd_core.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/hid/hid-picolcd_core.c b/drivers/hid/hid-picolcd_core.c > index acbb0210..020df3c 100644 > --- a/drivers/hid/hid-picolcd_core.c > +++ b/drivers/hid/hid-picolcd_core.c > @@ -350,6 +350,12 @@ static int picolcd_raw_event(struct hid_device *hdev, > if (!data) > return 1; > > + if (size > 64) { > + hid_warn(hdev, "invalid size value (%d) for picolcd raw event\n", > + size); Is it worth adding report->id to this hid_warn()? A valid device is not expected to ever send >64 bytes reports but in case a firmware update would do so it would help to know for which report it was. > + return 0; > + } > + > if (report->id == REPORT_KEY_STATE) { > if (data->input_keys) > ret = picolcd_raw_keypad(data, report, raw_data+1, size-1);