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 5A6D96FA1 for ; Mon, 3 Apr 2023 14:26:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6297C433D2; Mon, 3 Apr 2023 14:26:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1680532011; bh=NV7fsvGtmnS+yPXi6+sdyf+KKo0b63xITlaMufyYvXo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=F4FBtu06roWSHijdqEQTCGJVTlKBr1igB4gbFP6uEmHMepEzSUqWWXu2hzjaKB7Wi 8lyV5L6jgWKKtbGQqWQpZpMG6dNe5tI0HKjYXUCvlIdQypqsWOaDSbLHUjU9n+XIIm DxWOsjkCzUWcLr6gdrgQkb3akj/wULWUKsSOc+OY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Cristian Marussi , Sudeep Holla Subject: [PATCH 5.10 093/173] firmware: arm_scmi: Fix device node validation for mailbox transport Date: Mon, 3 Apr 2023 16:08:28 +0200 Message-Id: <20230403140417.439653438@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230403140414.174516815@linuxfoundation.org> References: <20230403140414.174516815@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(+) 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; -- 2.40.0