CVE-2022-42324

Published: 1 November 2022

Oxenstored 32->31 bit integer truncation issues Integers in Ocaml are 63 or 31 bits of signed precision. The Ocaml Xenbus library takes a C uint32_t out of the ring and casts it directly to an Ocaml integer. In 64-bit Ocaml builds this is fine, but in 32-bit builds, it truncates off the most significant bit, and then creates unsigned/signed confusion in the remainder. This in turn can feed a negative value into logic not expecting a negative value, resulting in unexpected exceptions being thrown. The unexpected exception is not handled suitably, creating a busy-loop trying (and failing) to take the bad packet out of the xenstore ring.

Notes

hypervisor packages are in universe. For
issues in the hypervisor, add appropriate
tags to each section, ex:
Tags_xen: universe-binary

Status

Severity score breakdown

References

• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-42324
• https://xenbits.xen.org/xsa/advisory-420.html
• https://xenbits.xenproject.org/xsa/advisory-420.txt
• http://xenbits.xen.org/xsa/advisory-420.html
• http://www.openwall.com/lists/oss-security/2022/11/01/10
• NVD
• Launchpad
• Debian