From: Chao Gao <chao.gao@intel.com>
Date: Wed, 1 Mar 2017 09:28:35 +0000 (+0100)
Subject: passthrough: reject self-(de)assignment of devices
X-Git-Tag: archive/raspbian/4.11.1-1+rpi1~1^2~66^2~2629
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success//%22http:/www.example.com/cgi/success/?a=commitdiff_plain;h=2c17e1836d46203f02f0ad699465500554575aef;p=xen.git

passthrough: reject self-(de)assignment of devices

That is to say, don't support a domain assigns a device to itself or detachs
a device from itself.

Signed-off-by: Chao Gao <chao.gao@intel.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---

diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index 338d6b4f37..beddd42701 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -1603,6 +1603,13 @@ int iommu_do_pci_domctl(
         break;
 
     case XEN_DOMCTL_assign_device:
+        /* Don't support self-assignment of devices. */
+        if ( d == current->domain )
+        {
+            ret = -EINVAL;
+            break;
+        }
+
         ret = -ENODEV;
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_PCI )
             break;
@@ -1643,6 +1650,13 @@ int iommu_do_pci_domctl(
         break;
 
     case XEN_DOMCTL_deassign_device:
+        /* Don't support self-deassignment of devices. */
+        if ( d == current->domain )
+        {
+            ret = -EINVAL;
+            break;
+        }
+
         ret = -ENODEV;
         if ( domctl->u.assign_device.dev != XEN_DOMCTL_DEV_PCI )
             break;