First published: Tue Jan 25 2022(Updated: )
A PV guest could DoS Xen while unmapping a grant To address XSA-380, reference counting was introduced for grant mappings for the case where a PV guest would have the IOMMU enabled. PV guests can request two forms of mappings. When both are in use for any individual mapping, unmapping of such a mapping can be requested in two steps. The reference count for such a mapping would then mistakenly be decremented twice. Underflow of the counters gets detected, resulting in the triggering of a hypervisor bug check.
Credit: security@xen.org
Affected Software | Affected Version | How to fix |
---|---|---|
Xen Xen | >=3.2.0<4.13.0 | |
Fedoraproject Fedora | =34 | |
Debian Debian Linux | =9.0 | |
Debian Debian Linux | =11.0 | |
debian/xen | <=4.11.4+107-gef32c7afa2-1 | 4.14.6-1 4.14.5+94-ge49571868d-1 4.17.1+2-gb773c48e36-1 4.17.2+55-g0b56bed864-1 |
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.