From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 93E918BE0 for ; Tue, 28 Mar 2023 15:12:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 192E0C4339B; Tue, 28 Mar 2023 15:12:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680016339; bh=DvhQgBvwcv5YSThhC09mPUGjr/dGWRvO+3jO04ceCFY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QtXiLCM429XDG48gNrn86c1CRgZCVnibCmZgqADjXu2RfVUnbbuTM16c9vYd6tq9K zNBOQdyafx6DU/iikanRhf81GkgMZf1qA+8likpL+nNyiDuc2p5iB/sjcLFJ3EoBAq MxplXxFMDw5eESVf2jbbYwZwD2RcAvTrh5hnrciA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Cristian Marussi , Sudeep Holla Subject: [PATCH 5.15 137/146] firmware: arm_scmi: Fix device node validation for mailbox transport Date: Tue, 28 Mar 2023 16:43:46 +0200 Message-Id: <20230328142608.384122999@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230328142602.660084725@linuxfoundation.org> References: <20230328142602.660084725@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Cristian Marussi commit 2ab4f4018cb6b8010ca5002c3bdc37783b5d28c2 upstream. 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 Link: https://lore.kernel.org/r/20230307162324.891866-1-cristian.marussi@arm.com Signed-off-by: Sudeep Holla Signed-off-by: Greg Kroah-Hartman --- drivers/firmware/arm_scmi/mailbox.c | 37 ++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) --- a/drivers/firmware/arm_scmi/mailbox.c +++ b/drivers/firmware/arm_scmi/mailbox.c @@ -52,6 +52,39 @@ static bool mailbox_chan_available(struc "#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 scm 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;