From 5f44d7e357f61f7be636a0e2e6d35453cbc3b589 Mon Sep 17 00:00:00 2001 From: Michal Privoznik Date: Thu, 8 Jun 2017 13:45:31 +0200 Subject: [PATCH] qemuDomainChangeNet: Forbid changing MTU https://bugzilla.redhat.com/show_bug.cgi?id=1447618 Currently, any attempt to change MTU on an interface that is plugged to a running domain is silently ignored. We should either do what's asked or error out. Well, we can update the host side of the interface, but we cannot change 'host_mtu' attribute for the virtio-net device. Therefore we have to error out. Signed-off-by: Michal Privoznik Reviewed-by: Laine Stump --- src/qemu/qemu_hotplug.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index 8066acae33..d46956d983 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c @@ -3138,6 +3138,12 @@ qemuDomainChangeNet(virQEMUDriverPtr driver, /* vlan can be modified, and will be checked later */ /* linkstate can be modified */ + if (olddev->mtu != newdev->mtu) { + virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s", + _("cannot modify MTU")); + goto cleanup; + } + /* allocate new actual device to compare to old - we will need to * free it if we fail for any reason */ -- 2.39.5