A parameter verification issue was discovered in Xen through 4.9.x. The function `alloc_heap_pages` allows callers to specify the first NUMA node that should be used for allocations through the `memflags` parameter; the node is extracted using the `MEMF_get_node` macro. While the function checks to see if the special constant `NUMA_NO_NODE` is specified, it otherwise does not handle the case where `node >= MAX_NUMNODES`. This allows an out-of-bounds access to an internal array.
The product reads data past the end, or before the beginning, of the intended buffer.
| Link | Tags |
|---|---|
| http://www.securityfocus.com/bid/100818 | vdb entry third party advisory |
| http://xenbits.xen.org/xsa/advisory-231.html | patch vendor advisory |
| https://support.citrix.com/article/CTX227185 | |
| https://www.debian.org/security/2017/dsa-4050 | vendor advisory |
| https://lists.debian.org/debian-lts-announce/2018/10/msg00009.html | mailing list |
| http://www.securitytracker.com/id/1039348 | vdb entry third party advisory |