Drivers: hv: vmbus: Don't free ring buffers that couldn't be re-encrypted
At a glance
Severity
CRITICAL 9.3
EPSS
EPSS 0.24 % · percentile 15 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified
Description
In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: vmbus: Don't free ring buffers that couldn't be re-encrypted
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
The VMBus ring buffer code could free decrypted/shared pages if
set_memory_decrypted() fails. Check the decrypted field in the struct
vmbus_gpadl for the ring buffers to decide whether to free the memory.
