Drivers: hv: vmbus: Leak pages if set_memory_encrypted() fails

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: vmbus: Leak pages if set_memory_encrypted() fails 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. VMBus code could free decrypted pages if set_memory_encrypted()/decrypted() fails. Leak the pages if this happens.

References

• https://git.kernel.org/stable/c/7f2afcbfe4f6b6047b5f68db5067b7321e5be125
• https://git.kernel.org/stable/c/6123a4e8e25bd40cf44db14694abac00e6b664e6
• https://git.kernel.org/stable/c/e813a0fc2e597146e9cebea61ced9c796d4e308f
• https://git.kernel.org/stable/c/03f5a999adba062456c8c818a683beb1b498983a