Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933022AbYBGUBi (ORCPT ); Thu, 7 Feb 2008 15:01:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932526AbYBGUB2 (ORCPT ); Thu, 7 Feb 2008 15:01:28 -0500 Received: from brick.kernel.dk ([87.55.233.238]:29715 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932569AbYBGUB1 (ORCPT ); Thu, 7 Feb 2008 15:01:27 -0500 Date: Thu, 7 Feb 2008 21:01:22 +0100 From: Jens Axboe To: Jesse Barnes Cc: Jan Engelhardt , linux-kernel@vger.kernel.org Subject: Re: out-of-bounds array index Message-ID: <20080207200121.GO15220@kernel.dk> References: <20080207185642.GN15220@kernel.dk> <200802071128.55935.jesse.barnes@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200802071128.55935.jesse.barnes@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1413 Lines: 38 On Thu, Feb 07 2008, Jesse Barnes wrote: > On Thursday, February 07, 2008 11:21 am Jan Engelhardt wrote: > > On Feb 7 2008 19:56, Jens Axboe wrote: > > >Just saw this from gcc: > > > > > >drivers/char/drm/i915_drv.c: In function ?i915_suspend?: > > >drivers/char/drm/i915_drv.c:173: warning: array subscript is above array > > >bounds > > > CC [M] drivers/char/drm/i915_dma.o > > >drivers/char/drm/i915_drv.c: In function ?i915_resume?: > > >drivers/char/drm/i915_drv.c:220: warning: array subscript is above array > > >bounds > > > > > >It's this code: > > > > > > dev_priv->saveGR[0x18] = > > > i915_read_indexed(VGA_GR_INDEX, VGA_GR_DATA, 0x18); > > > > > >which looks legit, since saveGR is > > > > It is not legit at all. 0x18 is the 25th position in the array, > > but it is only 24 big. (Excluding play-hide-and-seek games like > > allocating more in case of malloc or char *foo[0].) > > I think he was saying that the warning was legit. Anyway, my gcc isn't smart > enough to emit warnings like this, maybe it's time to ugprade... of course, the reference was to the warning (I do know C and array indexing 101 :-) -- Jens Axboe -- 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/