Virtio ring descriptors, and the data they describe are in a region of memory accessible by from both the virtual machine and the host. vhost_crypto.c frequently accesses the descriptors directly in the shared memory region. This is not safe. An attacker in the VM can change the contents of the memory after vhost_crypto has validated it. vhost_crypto.c needs to avoid processing data directly in the shared memory region. This can be exploited in the same way as finding number 1 to gain remote code execution and virtual machine escape.
Statement: This flaw does not affect the versions of `dpdk` as shipped with Red Hat Enterprise Linux 7 and 8 or the versions embedded in Red Hat Virtualization or the Fast Datapath `openvswitch` package, as they do not enable generic crypto device library support. This causes the vulnerable code in vhost_crypto.c to not be included. This flaw does not affect Red Hat Ceph Storage 3 and 4 as dpdk (embedded in ceph source rpm) is not built in the packages, therefore the vulnerable code is not available in the resulting RPM and the issue cannot be exploited.
Acknowledgments: Name: Ryan Hall
External References: https://www.openwall.com/lists/oss-security/2020/09/28/3
Created dpdk tracking bugs for this issue: Affects: fedora-all [bug 1883274]
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2020-14375