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 4CA12C41513 for ; Sat, 12 Aug 2023 14:09:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231639AbjHLOJ0 (ORCPT ); Sat, 12 Aug 2023 10:09:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53932 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233514AbjHLOJU (ORCPT ); Sat, 12 Aug 2023 10:09:20 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8FA81FEE; Sat, 12 Aug 2023 07:09:23 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 248D362493; Sat, 12 Aug 2023 14:09:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CEB08C433C8; Sat, 12 Aug 2023 14:09:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691849362; bh=z+m4uxf5uQXSYdBR7XRst5uEUqfj5OU0THhKy2Pgzw0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NRcuuSwRkCingBsl/vsEZbgeFFYLrf1y+jccW0/5Yc5HDj+1VoVAME8JmLoRwatmv cq9vWxL4zAE9ZVUJLta84Dvv5Inw/EfKSi/yAs63VyBxmpmvFYbATcUsu77nljsk2A aA3VJilGgMOpA/ket7dhpg569WOR9pO165Aa92NCsdjCCxPdIgZY5ieRy7nbUuFLnh 5IcBP4Gl/p7TKLadf1jSNE+GDBp+0bp0kFtLguMP/b1EWW/an8byu12FnBRohiFL9c uRJrWRUhrLp3tNfyj4R8So0k0XxPic0tJx3E0PAmnu0wkeyaegTrtitZo78/ruaSpI fW6TnxXPQeEnQ== Date: Sat, 12 Aug 2023 16:09:12 +0200 From: Simon Horman To: Gatien Chevallier Cc: Oleksii_Moisieiev@epam.com, gregkh@linuxfoundation.org, herbert@gondor.apana.org.au, davem@davemloft.net, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, alexandre.torgue@foss.st.com, vkoul@kernel.org, jic23@kernel.org, olivier.moysan@foss.st.com, arnaud.pouliquen@foss.st.com, mchehab@kernel.org, fabrice.gasnier@foss.st.com, andi.shyti@kernel.org, ulf.hansson@linaro.org, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, hugues.fruchet@foss.st.com, lee@kernel.org, will@kernel.org, catalin.marinas@arm.com, arnd@kernel.org, richardcochran@gmail.com, Frank Rowand , peng.fan@oss.nxp.com, linux-crypto@vger.kernel.org, devicetree@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, linux-i2c@vger.kernel.org, linux-iio@vger.kernel.org, alsa-devel@alsa-project.org, linux-media@vger.kernel.org, linux-mmc@vger.kernel.org, netdev@vger.kernel.org, linux-phy@lists.infradead.org, linux-serial@vger.kernel.org, linux-spi@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: [PATCH v4 05/11] firewall: introduce stm32_firewall framework Message-ID: References: <20230811100731.108145-1-gatien.chevallier@foss.st.com> <20230811100731.108145-6-gatien.chevallier@foss.st.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230811100731.108145-6-gatien.chevallier@foss.st.com> Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org On Fri, Aug 11, 2023 at 12:07:25PM +0200, Gatien Chevallier wrote: ... > diff --git a/drivers/bus/stm32_firewall.c b/drivers/bus/stm32_firewall.c > new file mode 100644 > index 000000000000..900f3b052a66 > --- /dev/null > +++ b/drivers/bus/stm32_firewall.c > @@ -0,0 +1,293 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2023, STMicroelectronics - All Rights Reserved > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include "stm32_firewall.h" > + > +/* Corresponds to STM32_FIREWALL_MAX_EXTRA_ARGS + firewall ID */ > +#define STM32_FIREWALL_MAX_ARGS (STM32_FIREWALL_MAX_EXTRA_ARGS + 1) > + > +static LIST_HEAD(firewall_controller_list); > +static DEFINE_MUTEX(firewall_controller_list_lock); > + > +/* Firewall device API */ > +int stm32_firewall_get_firewall(struct device_node *np, struct stm32_firewall *firewall, > + unsigned int nb_firewall) > +{ > + struct stm32_firewall_controller *ctrl; > + struct of_phandle_iterator it; > + unsigned int i, j = 0; > + int err; > + > + if (!firewall || !nb_firewall) > + return -EINVAL; > + > + /* Parse property with phandle parsed out */ > + of_for_each_phandle(&it, err, np, "feature-domains", "#feature-domain-cells", 0) { > + struct of_phandle_args provider_args; > + struct device_node *provider = it.node; > + const char *fw_entry; > + bool match = false; > + > + if (err) { > + pr_err("Unable to get feature-domains property for node %s\n, err: %d", > + np->full_name, err); > + of_node_put(provider); > + return err; > + } > + > + if (j > nb_firewall) { > + pr_err("Too many firewall controllers"); > + of_node_put(provider); > + return -EINVAL; > + } > + > + provider_args.args_count = of_phandle_iterator_args(&it, provider_args.args, > + STM32_FIREWALL_MAX_ARGS); > + > + /* Check if the parsed phandle corresponds to a registered firewall controller */ > + mutex_lock(&firewall_controller_list_lock); > + list_for_each_entry(ctrl, &firewall_controller_list, entry) { > + if (ctrl->dev->of_node->phandle == it.phandle) { > + match = true; > + firewall[j].firewall_ctrl = ctrl; > + break; > + } > + } > + mutex_unlock(&firewall_controller_list_lock); > + > + if (!match) { > + firewall[j].firewall_ctrl = NULL; > + pr_err("No firewall controller registered for %s\n", np->full_name); > + of_node_put(provider); > + return -ENODEV; > + } > + > + err = of_property_read_string_index(np, "feature-domain-names", j, &fw_entry); > + if (err == 0) > + firewall[j].entry = fw_entry; > + > + /* Handle the case when there are no arguments given along with the phandle */ > + if (provider_args.args_count < 0 || > + provider_args.args_count > STM32_FIREWALL_MAX_ARGS) { > + of_node_put(provider); > + return -EINVAL; > + } else if (provider_args.args_count == 0) { > + firewall[j].extra_args_size = 0; > + firewall[j].firewall_id = U32_MAX; > + j++; > + continue; > + } > + > + /* The firewall ID is always the first argument */ > + firewall[j].firewall_id = provider_args.args[0]; > + > + /* Extra args start at the third argument */ > + for (i = 0; i < provider_args.args_count; i++) > + firewall[j].extra_args[i] = provider_args.args[i + 1]; Hi Gatien, Above it is checked that the maximum value of provider_args.args_count is STM32_FIREWALL_MAX_ARGS. So here the maximum value of i is STM32_FIREWALL_MAX_ARGS - 1. STM32_FIREWALL_MAX_ARGS is defined as STM32_FIREWALL_MAX_EXTRA_ARGS + 1 And STM32_FIREWALL_MAX_EXTRA_ARGS is defined as 5. So the maximum value of i is (5 + 1 - 1) = 5. firewall[j] is of type struct stm32_firewall. And its args field has STM32_FIREWALL_MAX_EXTRA_ARGS (5) elements. Thus the maximum valid index is (5 - 1) = 4. But the line above may access index 5. Flagged by Smatch. > + > + /* Remove the firewall ID arg that is not an extra argument */ > + firewall[j].extra_args_size = provider_args.args_count - 1; > + > + j++; > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(stm32_firewall_get_firewall); ... > diff --git a/include/linux/bus/stm32_firewall_device.h b/include/linux/bus/stm32_firewall_device.h > new file mode 100644 > index 000000000000..7b4450a8ec15 > --- /dev/null > +++ b/include/linux/bus/stm32_firewall_device.h > @@ -0,0 +1,141 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2023, STMicroelectronics - All Rights Reserved > + */ > + > +#ifndef STM32_FIREWALL_DEVICE_H > +#define STM32_FIREWALL_DEVICE_H > + > +#include > +#include > +#include > + > +#define STM32_FIREWALL_MAX_EXTRA_ARGS 5 > + > +/* Opaque reference to stm32_firewall_controller */ > +struct stm32_firewall_controller; > + > +/** > + * struct stm32_firewall - Information on a device's firewall. Each device can have more than one > + * firewall. > + * > + * @firewall_ctrl: Pointer referencing a firewall controller of the device. It is > + * opaque so a device cannot manipulate the controller's ops or access > + * the controller's data > + * @extra_args: Extra arguments that are implementation dependent > + * @entry: Name of the firewall entry > + * @extra_args_size: Number of extra arguments > + * @firewall_id: Firewall ID associated the device for this firewall controller > + */ > +struct stm32_firewall { > + struct stm32_firewall_controller *firewall_ctrl; > + u32 extra_args[STM32_FIREWALL_MAX_EXTRA_ARGS]; > + const char *entry; > + size_t extra_args_size; > + u32 firewall_id; > +}; ...