From patchwork Fri Jun 4 09:14:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnaud POULIQUEN X-Patchwork-Id: 12299209 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6ED4C07E94 for ; Fri, 4 Jun 2021 09:14:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 90E866142C for ; Fri, 4 Jun 2021 09:14:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230046AbhFDJQI (ORCPT ); Fri, 4 Jun 2021 05:16:08 -0400 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:57392 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S229981AbhFDJQH (ORCPT ); Fri, 4 Jun 2021 05:16:07 -0400 Received: from pps.filterd (m0046661.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 15496lI2028502; Fri, 4 Jun 2021 11:14:19 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=selector1; bh=YzOrkrkHZq0r60g/e950hTfN5Vx2FE30j84KKoiKa8s=; b=iDxCxwmPHj4pe1jtp8nuWXAad7WC3SPcSo3FptZS6yD4N+qKTGRkxvQdm0J/iHzZk4pg Tv4v2vx6XBaC7imMqdQoUJYoxzg7UixstbifU56ULokajqbDCaPZoeqtR32qKrv9eM83 Ntz0XLDiCPuQ5EzBcoey904lFI1zYU/creVoHamtcC0cpigTn5A26UC8QKgpMKL3xRjk Ub+gkA4Ly6hS1y/S0l2CH8btWs5uAgQFG1E7WXu4gOsUDzKwveX1FSGBbpCXTGEgTP4S 8tfc2k6yutyaDJfRih3oLxZaEHPeQgCdjUtudP2MzJiG5uJWWdpJvAoJ5k84ZYaMS1Vz Pg== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 38yg960grh-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 04 Jun 2021 11:14:19 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 3BC7310002A; Fri, 4 Jun 2021 11:14:19 +0200 (CEST) Received: from Webmail-eu.st.com (sfhdag2node3.st.com [10.75.127.6]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 2F8A4216EEF; Fri, 4 Jun 2021 11:14:19 +0200 (CEST) Received: from localhost (10.75.127.51) by SFHDAG2NODE3.st.com (10.75.127.6) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Fri, 4 Jun 2021 11:14:18 +0200 From: Arnaud Pouliquen To: Bjorn Andersson , Ohad Ben-Cohen , Mathieu Poirier CC: , , , Subject: [PATCH 3/4] rpmsg: ctrl: Add check on rpmsg device removability from user space Date: Fri, 4 Jun 2021 11:14:05 +0200 Message-ID: <20210604091406.15901-4-arnaud.pouliquen@foss.st.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210604091406.15901-1-arnaud.pouliquen@foss.st.com> References: <20210604091406.15901-1-arnaud.pouliquen@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.75.127.51] X-ClientProxiedBy: SFHDAG3NODE2.st.com (10.75.127.8) To SFHDAG2NODE3.st.com (10.75.127.6) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.761 definitions=2021-06-04_05:2021-06-04,2021-06-04 signatures=0 Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org Using the RPMSG_RELEASE_DEV_IOCTL is possible to remove any rpmsg device (such as the rpmsg ns or the rpmsg ctrldev). Add a new field to store the removability of the device. By default the rpmsg device can not be removed by user space. It is set to 1 by the rpmsg ctrl on RPMSG_CREATE_DEV_IOCTL request, but could also be set by an rpmsg driver during probe. Signed-off-by: Arnaud Pouliquen --- drivers/rpmsg/rpmsg_ctrl.c | 17 ++++++++++++++++- include/linux/rpmsg.h | 2 ++ 2 files changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c index cb19e32d05e1..e93c6ec49038 100644 --- a/drivers/rpmsg/rpmsg_ctrl.c +++ b/drivers/rpmsg/rpmsg_ctrl.c @@ -74,6 +74,7 @@ static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd, struct rpmsg_endpoint_info eptinfo; struct rpmsg_channel_info chinfo; struct rpmsg_device *rpdev; + struct device *dev; int ret = 0; if (copy_from_user(&eptinfo, argp, sizeof(eptinfo))) @@ -95,11 +96,25 @@ static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd, if (!rpdev) { dev_err(&ctrldev->dev, "failed to create %s channel\n", chinfo.name); ret = -ENXIO; + } else { + /* Allow user space to release the device. */ + rpdev->us_removable = 1; } break; case RPMSG_RELEASE_DEV_IOCTL: - ret = rpmsg_release_channel(ctrldev->rpdev, &chinfo); + dev = rpmsg_find_device(ctrldev->rpdev->dev.parent, &chinfo); + if (!dev) + ret = -ENXIO; + + /* Verify that rpmsg device removal is allowed. */ + if (!ret) { + rpdev = to_rpmsg_device(dev); + if (!rpdev->us_removable) + ret = -EACCES; + } + if (!ret) + ret = rpmsg_release_channel(ctrldev->rpdev, &chinfo); if (ret) dev_err(&ctrldev->dev, "failed to release %s channel (%d)\n", chinfo.name, ret); diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index d97dcd049f18..3642aad1a789 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -47,6 +47,7 @@ struct rpmsg_channel_info { * @ept: the rpmsg endpoint of this channel * @announce: if set, rpmsg will announce the creation/removal of this channel * @little_endian: True if transport is using little endian byte representation + * @us_removable: True if userspace application has permission to remove the rpmsg device */ struct rpmsg_device { struct device dev; @@ -57,6 +58,7 @@ struct rpmsg_device { struct rpmsg_endpoint *ept; bool announce; bool little_endian; + bool us_removable; const struct rpmsg_device_ops *ops; };