An issue was discovered in Xen 4.14.x. When moving IRQs between CPUs to distribute the load of IRQ handling, IRQ vectors are dynamically allocated and de-allocated on the relevant CPUs. De-allocation has to happen when certain constraints are met. If these conditions are not met when first checked, the checking CPU may send an interrupt to itself, in the expectation that this IRQ will be delivered only after the condition preventing the cleanup has cleared. For two specific IRQ vectors, this expectation was violated, resulting in a continuous stream of self-interrupts, which renders the CPU effectively unusable. A domain with a passed through PCI device can cause lockup of a physical CPU, resulting in a Denial of Service (DoS) to the entire host. Only x86 systems are vulnerable. Arm systems are not vulnerable. Only guests with physical PCI devices passed through to them can exploit the vulnerability.
References
Link | Resource |
---|---|
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI/ | |
https://security.gentoo.org/glsa/202107-30 | Third Party Advisory |
https://xenbits.xenproject.org/xsa/advisory-356.html | Patch Vendor Advisory |
History
No history.
MITRE Information
Status: PUBLISHED
Assigner: mitre
Published: 2020-12-15T16:50:37
Updated: 2021-07-12T04:06:23
Reserved: 2020-12-04T00:00:00
Link: CVE-2020-29567
JSON object: View
NVD Information
Status : Modified
Published: 2020-12-15T17:15:14.597
Modified: 2023-11-07T03:21:31.870
Link: CVE-2020-29567
JSON object: View
Redhat Information
No data.
CWE