Align source_buffer in enclave_load_data

See intel/confidential-computing.sgx#844

Author: Jethro Beekman

intel-sgx/sgxs-loaders/src/sgx_enclave_common/defs.rs

@@ -56,6 +56,9 @@ pub const LIBRARY: &str = "libsgx_enclave_common.so.1";
 #[cfg(windows)]
 pub const LIBRARY: &str = "sgx_enclave_common.dll";
 
+#[repr(align(4096))]
+pub struct Align4096<T>(pub T);
+
 pub const SYM_ENCLAVE_CREATE: &[u8] = b"enclave_create\0";
 pub type EnclaveCreateFn = unsafe extern "C" fn(
     base_address: *mut c_void,
@@ -71,7 +74,7 @@ pub const SYM_ENCLAVE_LOAD_DATA: &[u8] = b"enclave_load_data\0";
 pub type EnclaveLoadDataFn = unsafe extern "C" fn(
     target_address: *mut c_void,
     target_size: usize,
-    source_buffer: *const u8,
+    source_buffer: *const Align4096<[u8; 4096]>,
     data_properties: PageProperties,
     enclave_error: Option<&mut u32>,
 ) -> usize;

intel-sgx/sgxs-loaders/src/sgx_enclave_common/mod.rs

@@ -173,6 +173,7 @@ impl EnclaveLoad for InnerLibrary {
         page: (MeasEAdd, PageChunks, [u8; 4096]),
     ) -> Result<(), Self::Error> {
         let (eadd, chunks, data) = page;
+        let data = Align4096(data);
 
         let mut flags = PageProperties::empty();
         if eadd
@@ -207,7 +208,7 @@ impl EnclaveLoad for InnerLibrary {
             if (mapping.device.enclave_load_data)(
                 (mapping.base + eadd.offset) as _,
                 0x1000,
-                data.as_ptr(),
+                &data,
                 flags,
                 Some(&mut error),
             ) != 0x1000