The xenmem_add_to_physmap_one function in arch/arm/mm.c in Xen 4.5.x, 4.4.x, and earlier does not limit the number of printk console messages when reporting a failure to retrieve a reference on a foreign page, which allows remote domains to cause a denial of service by leveraging permissions to map the memory of a foreign guest.

References

• https://nvd.nist.gov/vuln/detail/CVE-2015-6654
• http://www.debian.org/security/2015/dsa-3414
• http://www.securitytracker.com/id/1033438
• http://xenbits.xen.org/xsa/advisory-141.html