From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BAF2CC6FD18 for ; Wed, 29 Mar 2023 23:59:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229917AbjC2X7X (ORCPT ); Wed, 29 Mar 2023 19:59:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229763AbjC2X7W (ORCPT ); Wed, 29 Mar 2023 19:59:22 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C9CF3C03 for ; Wed, 29 Mar 2023 16:59:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1680134361; x=1711670361; h=message-id:date:mime-version:subject:to:references:from: in-reply-to:content-transfer-encoding; bh=SllLy98lboAQE6T/4iT0OsGN7/87AVlLaTbLqjhz2qk=; b=DmB5QO9KTtEENkjHcvQRlexplfTwQ6cgS+Tu2DGTe7rBgqw62c2h69Kq BBtaWNKJT4V+zuDES15crttumnaVa2sM9xIHgQSTSZjduu0LHK/KaRcmm scSn9jtmPnYur2woHgFq4ndfQkcSryzOpr10SYUHgd88Wp34kxv42S8Eh w6oqzKYMTVKX0hjyCRyLKSNpobmSXURoHqp8QNX2DZb9gZxHDGVMWsMFi 0q9i27jKllzTyDfLH9lWCH8ZFVoKO8AAk+Z64lSvmzgB24zetYE39BQ+m O442T7hYNOmBKopZR+jgNauzoUYdhjoR7ReFrY0+YsiOP389ODgwi10Bf Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10664"; a="343476937" X-IronPort-AV: E=Sophos;i="5.98,301,1673942400"; d="scan'208";a="343476937" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Mar 2023 16:59:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10664"; a="748960150" X-IronPort-AV: E=Sophos;i="5.98,301,1673942400"; d="scan'208";a="748960150" Received: from djiang5-mobl3.amr.corp.intel.com (HELO [10.212.109.34]) ([10.212.109.34]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Mar 2023 16:59:21 -0700 Message-ID: <76fc93c5-bc5b-45e3-8e85-3b6ea48d013c@intel.com> Date: Wed, 29 Mar 2023 16:59:20 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.9.0 Subject: Re: [PATCH] cxl/hdm: Avoid NULL deref when component registers are missing Content-Language: en-US To: Dan Williams , linux-cxl@vger.kernel.org References: <168012574357.221280.5001364964799725366.stgit@dwillia2-xfh.jf.intel.com> From: Dave Jiang In-Reply-To: <168012574357.221280.5001364964799725366.stgit@dwillia2-xfh.jf.intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On 3/29/23 2:35 PM, Dan Williams wrote: > The cxl_port driver attempts to support endpoint devices that do not > advertise a component register block, but by inspection > devm_cxl_setup_hdm() passes a NULL @crb to helper functions that should > be skipped. > > Return early and skip setting target_count since that is only relevant > for switch decoders, not endpoint decoders. > > Fixes: 757f6448b100 ("cxl/hdm: Fix double allocation of @cxlhdm") > Tested-by: Dave Jiang > Signed-off-by: Dan Williams Reviewed-by: Dave Jiang > --- > drivers/cxl/core/hdm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c > index 5293fe13fce3..cc123996b1a4 100644 > --- a/drivers/cxl/core/hdm.c > +++ b/drivers/cxl/core/hdm.c > @@ -123,7 +123,7 @@ struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port, > crb = ioremap(port->component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE); > if (!crb && info && info->mem_enabled) { > cxlhdm->decoder_count = info->ranges; > - cxlhdm->target_count = info->ranges; > + return cxlhdm; > } else if (!crb) { > dev_err(dev, "No component registers mapped\n"); > return ERR_PTR(-ENXIO); >