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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7322BEE01ED for ; Wed, 13 Sep 2023 16:58:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qgTC2-00024l-0q; Wed, 13 Sep 2023 12:58:22 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgTBz-00024Z-MX for qemu-devel@nongnu.org; Wed, 13 Sep 2023 12:58:19 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qgTBx-0004iv-Hw for qemu-devel@nongnu.org; Wed, 13 Sep 2023 12:58:19 -0400 Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Rm63L5jDgz6D94k; Thu, 14 Sep 2023 00:53:34 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Wed, 13 Sep 2023 17:58:14 +0100 Date: Wed, 13 Sep 2023 17:58:13 +0100 To: Dmitry Frolov CC: , , Subject: Re: [PATCH v2] hw/cxl: Fix out of bound array access Message-ID: <20230913175813.00005d11@Huawei.com> In-Reply-To: <20230913132227.823336-1-frolov@swemel.ru> References: <057bee7c-92e0-1cf2-bcdd-ef7eeb223db4@linaro.org> <20230913132227.823336-1-frolov@swemel.ru> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml500003.china.huawei.com (7.191.162.67) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=185.176.79.56; envelope-from=jonathan.cameron@huawei.com; helo=frasgout.his.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: Jonathan Cameron From: Jonathan Cameron via Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, 13 Sep 2023 16:22:28 +0300 Dmitry Frolov wrote: > According to cxl_interleave_ways_enc(), > fw->num_targets is allowed to be up to 16. > This also corresponds to CXL specs. > So, the fw->target_hbs[] array is iterated from 0 to 15. > But it is staticaly declared of length 8. > Thus, out of bound array access may occur. > > Fixes: c28db9e000 ("hw/pci-bridge: Make PCIe and CXL PXB Devices inherit from TYPE_PXB_DEV") > > Signed-off-by: Dmitry Frolov > --- > v2: assert added > --- > hw/cxl/cxl-host.c | 1 + > include/hw/cxl/cxl.h | 2 +- > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c > index 034c7805b3..fe9143409b 100644 > --- a/hw/cxl/cxl-host.c > +++ b/hw/cxl/cxl-host.c > @@ -33,6 +33,7 @@ static void cxl_fixed_memory_window_config(CXLState *cxl_state, > for (target = object->targets; target; target = target->next) { > fw->num_targets++; > } > + assert(fw->num_targets <= ARRAY_SIZE(fw->target_hbs)); Just incase it gets lost as I replied late to the v1 comment. This is both unnecessary and results in an assert for a case that would otherwise be a nice error message about unsupported number of interleave ways. Jonathan > > fw->enc_int_ways = cxl_interleave_ways_enc(fw->num_targets, errp); > if (*errp) { > diff --git a/include/hw/cxl/cxl.h b/include/hw/cxl/cxl.h > index 56c9e7676e..4944725849 100644 > --- a/include/hw/cxl/cxl.h > +++ b/include/hw/cxl/cxl.h > @@ -29,7 +29,7 @@ typedef struct PXBCXLDev PXBCXLDev; > typedef struct CXLFixedWindow { > uint64_t size; > char **targets; > - PXBCXLDev *target_hbs[8]; > + PXBCXLDev *target_hbs[16]; > uint8_t num_targets; > uint8_t enc_int_ways; > uint8_t enc_int_gran;