CVE-2022-42324

Description

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.

Weakness classification

• CWE-681: Incorrect Conversion between Numeric Types

Primary references

• security@xen.org — Mailing List, Patch, Third Party Advisory
• security@xen.org — Patch, Vendor Advisory
• security@xen.org
• security@xen.org
• security@xen.org
• security@xen.org
• security@xen.org — Third Party Advisory
• security@xen.org — Patch, Vendor Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Mailing List, Patch, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Patch, Vendor Advisory
• af854a3a-2127-422b-91ae-364da2661108
• af854a3a-2127-422b-91ae-364da2661108