Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753418AbaGAGuc (ORCPT ); Tue, 1 Jul 2014 02:50:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:23647 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753028AbaGAGua (ORCPT ); Tue, 1 Jul 2014 02:50:30 -0400 Date: Tue, 1 Jul 2014 08:50:22 +0200 From: Mateusz Guzik To: Jiri Kosina Cc: Nicholas Krause , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] hid-appleir: Fix kernel panic due to null pointer Message-ID: <20140701065021.GA887@mguzik.redhat.com> References: <1404180865-3681-1-git-send-email-xerofoify@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 01, 2014 at 08:39:06AM +0200, Jiri Kosina wrote: > On Mon, 30 Jun 2014, Nicholas Krause wrote: > > > Fixes a null pointer in appleir_input_configured due to reading > > into wrong size array. Changed the variable to input_dev->keycodemax. > > This is a stale changelog from the previous buggy version. > > > Signed-off-by: Nicholas Krause > > --- > > drivers/hid/hid-appleir.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/hid/hid-appleir.c b/drivers/hid/hid-appleir.c > > index 0e6a42d..cc02df4 100644 > > --- a/drivers/hid/hid-appleir.c > > +++ b/drivers/hid/hid-appleir.c > > @@ -272,7 +272,7 @@ static void appleir_input_configured(struct hid_device *hid, > > input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_REP); > > > > memcpy(appleir->keymap, appleir_key_table, sizeof(appleir->keymap)); > > - for (i = 0; i < ARRAY_SIZE(appleir_key_table); i++) > > + for (i = 0; i < appleir->keymap; i++) > > This is wrong. appleir->keymap is an array, and you want to count its > elements. > But where the claim of 'null pointer' is coming from (or reading/writing past the array for that matter)? Replacing appleir_key_table with appleir->keymap is a noop anyway because: unsigned short keymap[ARRAY_SIZE(appleir_key_table)]; although one may argue is slightly nicer since it is used in memcpy line earlier. -- Mateusz Guzik -- 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/