REDHAT-BUG-2537015: Medium severity DPDK vhost library vulnerability
A flaw was found in the DPDK vhost library. When handling a virtio indirect descriptor table, the host reads the table length more than once from guest memory and can allocate a host copy before validating that length. A guest that changes the length between those reads, or that supplies an out-of-range next index on a small host copy in the vDPA relay path, can cause the host vhost process to walk past the validated mapping or heap copy. That can crash or disrupt the vhost process. Out-of-bounds bytes are consumed as descriptor fields for GPA translation and are not returned to the guest as payload. This is a residual issue in the non-contiguous indirect descriptor copy path introduced as part of the CVE-2018-1059 fix.
Affected Software
Event History
Frequently Asked Questions
Which deployments are exposed?
Deployments using the DPDK vhost library to handle virtio indirect descriptor tables are affected. The out-of-range next-index condition specifically involves the vDPA relay path.
What does an attacker need to do to trigger the flaw?
An attacker needs control of a guest that can provide a virtio indirect descriptor table. They can change the table length between host reads or supply an out-of-range next index when the host has made a small copy of the table.
Can this issue expose host memory contents to the guest?
The described out-of-bounds bytes are consumed as descriptor fields for GPA translation and are not returned to the guest as payload. The stated impact is a crash or disruption of the host vhost process.