The qdisk PV disk backend in the qemu-xen flavour of qemu ("upstream
qemu") can be influenced by a malicious frontend to leak mapped grant
references.
A malicious HVM guest can cause the backend domain to run out of grant
references, leading to a DoS for any other domain which shares that
driver domain.
Acknowledgements:
Red Hat would like to thank the Xen project for reporting this issue.
Statement:
Not vulnerable.
This issue does not affect the versions of the xen package as shipped with Red Hat Enterprise Linux 5 as it does not provide support for the qdisk PV backend.
This issue does not affect the versions of qemu-kvm as shipped with Red Hat Enterprise Linux 6 as they did not include the upstream commit that introduced this flaw.
This issue does not affect Red Hat Enterprise MRG 2.
The qdisk PV disk backend in the qemu-xen flavour of qemu ("upstream qemu") can be influenced by a malicious frontend to leak mapped grant references. A malicious HVM guest can cause the backend domain to run out of grant references, leading to a DoS for any other domain which shares that driver domain. Acknowledgements: Red Hat would like to thank the Xen project for reporting this issue.