>You can't
have dom0s on a hostile network if you want to prevent these "rogue
>>migrations". Note that you can't force an outgoing migration
from a node, so >nobody can "steal" your running domUs. However, if
someone gets on a segment >of network that can reach your dom0s they
could send you some domUs of their
... >own
- shouldn't be a security issue (the domUs will still be isolated by Xen)
>but could get quite annoying ;-)
It's actually a
huge security hole since a migrating domU carries its device mappings to the
target machine. Basically, you could create domU, map one of
its disks to say /dev/hdb, migrate it to a target machine and gain access
to /dev/hdb on the target. Same goes for any file used as a
disk on the source/target dom0.
Minimally, Xen
should implement a simple hosts.allow hosts.deny mechanism for migration so that
a host can limit which other hosts can migrate in. Relying on
network isolation using a separate management network isn't always
practical.
Alan
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