When introducing of flatview_{read,write}, calls to address_space_to_flatview were placed outside RCU critical sections. This is wrong and has to be fixed; even though it is unlikely to happen with standard operating systems, malicious code could use it to trigger use-after-free and heap corruption. Patches posted upstream at: http://patchew.org/QEMU/20180305083655.6186-1-pbonzini@redhat.com/
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2018:3443