Wei Liu

In CoCo VMs, it is possible for the untrusted host to cause `set memory encrypted()` or `set memory decrypted()` to fail, resulting in shared memory. Callers need to handle these errors to avoid returning decrypted (shared) memory to the page allocator, which could lead to functional or security issues. The `netvsc` driver could free decrypted/shared pages if `set memory decrypted()` fails. Checking the `decrypted` field in the `gpadl` can decide whether to free the memory.

An issue allows ARM guest OS users to cause a denial of service, preventing physical CPU usage, due to lock mishandling when an add-to-physmap error is detected.

The issue allows local OS guest administrators to cause a denial of service or gain host OS privileges by manipulating information in guest-controlled areas of xenstore. This can lead to resource consumption or management facility confusion.

The issue allows local guest OS users with access to the driver domain to cause a denial of service by manipulating information in the backend directories in xenstore. This can lead to management tool confusion.

The issue allows local guest administrators to cause a denial of service, resulting in a "scheduling while atomic" error and host crash, by sending a malformed packet. This occurs when using certain Linux versions that do not allow sleeping in softirq context, causing a mutex to be taken when trying to disable the interface.