[Pkg-xen-devel] Bug#859560: xen: CVE-2017-7228: x86: broken check in memory_exchange() permits PV guest breakout (XSA-212)

[Salvatore Bonaccorso]

Source: xen
Version: 4.8.1~pre.2017.01.23-1
Severity: grave
Tags: security upstream
Justification: user security hole

Hi,

the following vulnerability was published for xen.

CVE-2017-7228[0]:
| An issue (known as XSA-212) was discovered in Xen, with fixes available
| for 4.8.x, 4.7.x, 4.6.x, 4.5.x, and 4.4.x. The earlier XSA-29 fix
| introduced an insufficient check on XENMEM_exchange input, allowing the
| caller to drive hypervisor memory accesses outside of the guest
| provided input/output arrays.

If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2017-7228
    https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-7228
[1] https://xenbits.xen.org/xsa/advisory-212.html

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore