From bad40f7148a5849e84e9cdc341ff1fa03dc94fc6 Mon Sep 17 00:00:00 2001
Message-Id: <bad40f7148a5849e84e9cdc341ff1fa03dc94fc6@dist-git>
From: Thomas Huth <thuth@redhat.com>
Date: Tue, 11 May 2021 14:10:27 +0200
Subject: [PATCH] hostdev: Update mdev pointer reference after checking device
 type
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We set the pointer to some garbage packed structure data without
knowing whether we were actually handling the type of device we
expected to be handling. On its own, this was harmless, because we'd
never use the pointer as we'd skip the device if it were not the
expected type. However, it's better to make the logic even more
explicit - we first check the device and only when we're sure we have
the expected type we then update the pointer shortcut.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
(cherry picked from commit 964738cff3d949d90fc5c3317a2618fcd8d217b4)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1940449
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210511121028.304070-2-thuth@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
---
 src/util/virhostdev.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/util/virhostdev.c b/src/util/virhostdev.c
index 9596482146..b7050e99e4 100644
--- a/src/util/virhostdev.c
+++ b/src/util/virhostdev.c
@@ -2030,11 +2030,11 @@ virHostdevReAttachMediatedDevices(virHostdevManagerPtr mgr,
         virDomainHostdevSubsysMediatedDevPtr mdevsrc;
         virDomainHostdevDefPtr hostdev = hostdevs[i];
 
-        mdevsrc = &hostdev->source.subsys.u.mdev;
-
         if (!virHostdevIsMdevDevice(hostdev))
             continue;
 
+        mdevsrc = &hostdev->source.subsys.u.mdev;
+
         if (!(mdev = virMediatedDeviceNew(mdevsrc->uuidstr,
                                           mdevsrc->model)))
             continue;
-- 
2.31.1