From patchwork Tue Mar 7 16:23:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cristian Marussi X-Patchwork-Id: 13164122 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 B8D48C6FD1A for ; Tue, 7 Mar 2023 16:24:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=+58Bb1QfYuPcYz8gG94h0qY0gL/8p0nTE9CmoBT4r/o=; b=O/FSG78v+8wJtV lBW+HolWRAJSyOjIbyPG+/Mtlm1KlthC38cKpA4fdqLuddTaAXxfp5idUWo145K/RSQK/8x5b/Rdi fQHm7Bz71Vd0I+jz+EXYBFz+vQUqxPmA0VMcQVk4HW5VpznsCqL0dh554DmG8oWHfe/7BDvIk3MQD bSsEfnhu31qcmxv02piszy1Do/8SK0znL6mV3IPjO8KVRgHCZH3ImsZmDXN0RG9XOOfKfwsJiY2cd Z/ICJaXTVuzUEKfHtGo2Y4S4OdSv+HcgoMO/+/fgNQn5NsIncapihPFwszJuIFjGvmftO6UnYI564 4MJVCfnEqvgY+6BtflVA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pZa6c-001W43-E2; Tue, 07 Mar 2023 16:24:02 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pZa6X-001W0c-MI for linux-arm-kernel@lists.infradead.org; Tue, 07 Mar 2023 16:23:59 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A106D1C2B; Tue, 7 Mar 2023 08:24:32 -0800 (PST) Received: from e120937-lin.. (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2D9E63F67D; Tue, 7 Mar 2023 08:23:48 -0800 (PST) From: Cristian Marussi To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: sudeep.holla@arm.com, viresh.kumar@linaro.org, vincent.guittot@linaro.org, Cristian Marussi , stable@vger.kernel.org Subject: [PATCH] firmware: arm_scmi: Fix device node validation for mailbox transport Date: Tue, 7 Mar 2023 16:23:24 +0000 Message-Id: <20230307162324.891866-1-cristian.marussi@arm.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230307_082357_833701_A96A37A4 X-CRM114-Status: GOOD ( 12.15 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org When mailboxes are used as a transport it is possible to setup the SCMI transport layer, depending on the underlying channels configuration, to use one or two mailboxes, associated, respectively, to one or two, distinct, shared memory areas: any other combination should be treated as invalid. Add more strict checking of SCMI mailbox transport device node descriptors. Fixes: 5c8a47a5a91d ("firmware: arm_scmi: Make scmi core independent of the transport type") Cc: # 4.19 Signed-off-by: Cristian Marussi --- drivers/firmware/arm_scmi/mailbox.c | 37 +++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c index 0d9c9538b7f4..112c285deb97 100644 --- a/drivers/firmware/arm_scmi/mailbox.c +++ b/drivers/firmware/arm_scmi/mailbox.c @@ -52,6 +52,39 @@ static bool mailbox_chan_available(struct device_node *of_node, int idx) "#mbox-cells", idx, NULL); } +static int mailbox_chan_validate(struct device *cdev) +{ + int num_mb, num_sh, ret = 0; + struct device_node *np = cdev->of_node; + + num_mb = of_count_phandle_with_args(np, "mboxes", "#mbox-cells"); + num_sh = of_count_phandle_with_args(np, "shmem", NULL); + /* Bail out if mboxes and shmem descriptors are inconsistent */ + if (num_mb <= 0 || num_sh > 2 || num_mb != num_sh) { + dev_warn(cdev, "Invalid channel descriptor for '%s'\n", + of_node_full_name(np)); + return -EINVAL; + } + + if (num_sh > 1) { + struct device_node *np_tx, *np_rx; + + np_tx = of_parse_phandle(np, "shmem", 0); + np_rx = of_parse_phandle(np, "shmem", 1); + /* SCMI Tx and Rx shared mem areas have to be distinct */ + if (!np_tx || !np_rx || np_tx == np_rx) { + dev_warn(cdev, "Invalid shmem descriptor for '%s'\n", + of_node_full_name(np)); + ret = -EINVAL; + } + + of_node_put(np_tx); + of_node_put(np_rx); + } + + return ret; +} + static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, bool tx) { @@ -64,6 +97,10 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, resource_size_t size; struct resource res; + ret = mailbox_chan_validate(cdev); + if (ret) + return ret; + smbox = devm_kzalloc(dev, sizeof(*smbox), GFP_KERNEL); if (!smbox) return -ENOMEM;