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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 0CAB3C43603 for ; Thu, 5 Dec 2019 03:34:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2CE22073B for ; Thu, 5 Dec 2019 03:34:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728904AbfLEDeT (ORCPT ); Wed, 4 Dec 2019 22:34:19 -0500 Received: from mga12.intel.com ([192.55.52.136]:43800 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728821AbfLEDeT (ORCPT ); Wed, 4 Dec 2019 22:34:19 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Dec 2019 19:34:19 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,279,1571727600"; d="scan'208";a="243094962" Received: from joy-optiplex-7040.sh.intel.com ([10.239.13.9]) by fmsmga002.fm.intel.com with ESMTP; 04 Dec 2019 19:34:16 -0800 From: Yan Zhao To: alex.williamson@redhat.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, libvir-list@redhat.com, qemu-devel@nongnu.org, cohuck@redhat.com, zhenyuw@linux.intel.com, zhi.a.wang@intel.com, kevin.tian@intel.com, shaopeng.he@intel.com, Yan Zhao Subject: [RFC PATCH 2/9] vfio/pci: test existence before calling region->ops Date: Wed, 4 Dec 2019 22:25:55 -0500 Message-Id: <20191205032555.29700-1-yan.y.zhao@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191205032419.29606-1-yan.y.zhao@intel.com> References: <20191205032419.29606-1-yan.y.zhao@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For regions registered through vfio_pci_register_dev_region(), before calling region->ops, first check whether region->ops is not null. As in the next two patches, dev regions of null region->ops are to be registered by default on behalf of vendor driver, we need to check here to prevent null pointer access if vendor driver forgets to handle those dev regions Cc: Kevin Tian Signed-off-by: Yan Zhao --- drivers/vfio/pci/vfio_pci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 55080ff29495..f3730252ee82 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -398,8 +398,12 @@ static void vfio_pci_disable(struct vfio_pci_device *vdev) vdev->virq_disabled = false; - for (i = 0; i < vdev->num_regions; i++) + for (i = 0; i < vdev->num_regions; i++) { + if (!vdev->region[i].ops || vdev->region[i].ops->release) + continue; + vdev->region[i].ops->release(vdev, &vdev->region[i]); + } vdev->num_regions = 0; kfree(vdev->region); @@ -900,7 +904,8 @@ static long vfio_pci_ioctl(void *device_data, if (ret) return ret; - if (vdev->region[i].ops->add_capability) { + if (vdev->region[i].ops && + vdev->region[i].ops->add_capability) { ret = vdev->region[i].ops->add_capability(vdev, &vdev->region[i], &caps); if (ret) @@ -1251,6 +1256,9 @@ static ssize_t vfio_pci_rw(void *device_data, char __user *buf, return vfio_pci_vga_rw(vdev, buf, count, ppos, iswrite); default: index -= VFIO_PCI_NUM_REGIONS; + if (!vdev->region[index].ops || !vdev->region[index].ops->rw) + return -EINVAL; + return vdev->region[index].ops->rw(vdev, buf, count, ppos, iswrite); } -- 2.17.1