misc: tdx: make tdx_init_memory_region() unsafe

It takes a pointer to a userspace address that it accesses, so it should
be marked unsafe.  This was missed earlier.

Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>

hypervisor/src/kvm/mod.rs

@@ -1020,11 +1020,13 @@ impl vm::Vm for KvmVm {
         .map_err(vm::HypervisorVmError::FinalizeTdx)
     }
 
-    ///
     /// Initialize memory regions for the TDX VM
     ///
+    /// # Safety
+    ///
+    /// `host_address` must be valid for `size` bytes
     #[cfg(feature = "tdx")]
-    fn tdx_init_memory_region(
+    unsafe fn tdx_init_memory_region(
         &self,
         host_address: *mut u8,
         guest_address: u64,

hypervisor/src/vm.rs

@@ -401,7 +401,11 @@ pub trait Vm: Send + Sync + Any {
     }
     #[cfg(feature = "tdx")]
     /// Initialize a TDX memory region for this VM
-    fn tdx_init_memory_region(
+    ///
+    /// # Safety
+    ///
+    /// `_host_address` must be valid for `_size` bytes
+    unsafe fn tdx_init_memory_region(
         &self,
         _host_address: *mut u8,
         _guest_address: u64,

vmm/src/vm.rs

@@ -2249,15 +2249,23 @@ impl Vm {
         let mem = guest_memory.memory();
 
         for section in sections {
-            self.vm
+            let size = section.size.try_into().unwrap();
-                .tdx_init_memory_region(
+            // SAFETY: get_host_address_range does proper bounds checking
-                    mem.get_host_address(GuestAddress(section.address)).unwrap(),
+            unsafe {
+                self.vm.tdx_init_memory_region(
+                    virtio_devices::get_host_address_range(
+                        &*mem,
+                        GuestAddress(section.address),
+                        size,
+                    )
+                    .unwrap(),
                     section.address,
-                    section.size.try_into().unwrap(),
+                    size,
                     /* TDVF_SECTION_ATTRIBUTES_EXTENDMR */
                     section.attributes == 1,
                 )
-                .map_err(Error::InitializeTdxMemoryRegion)?;
+            }
+            .map_err(Error::InitializeTdxMemoryRegion)?;
         }
 
         Ok(())