Fix driver verifier failure due to not setting the flag to indicate pages are locked (#653)

* Fix driver verifier failure due to not setting the flag to indicate pages are locked

Signed-off-by: Alan Jowett <alanjo@microsoft.com>

* PR feedback

Signed-off-by: Alan Jowett <alanjo@microsoft.com>

libs/platform/kernel/ebpf_platform_kernel.c

@@ -203,18 +203,20 @@ ebpf_allocate_ring_buffer_memory(size_t length)
     source_mdl = &ring_descriptor->memory->memory_descriptor_list;
 
     // Create a MDL big enough to double map the pages.
-    ring_descriptor->memory_descriptor_list = IoAllocateMdl(
+    ring_descriptor->memory_descriptor_list =
-        ebpf_memory_descriptor_get_base_address(ring_descriptor->memory),
+        IoAllocateMdl(NULL, (uint32_t)(requested_page_count * 2 * PAGE_SIZE), FALSE, FALSE, NULL);
-        (uint32_t)(requested_page_count * 2 * PAGE_SIZE),
-        FALSE,
-        FALSE,
-        NULL);
     if (!ring_descriptor->memory_descriptor_list) {
         EBPF_LOG_NTSTATUS_API_FAILURE(EBPF_TRACELOG_KEYWORD_BASE, IoAllocateMdl, STATUS_NO_MEMORY);
         status = STATUS_NO_MEMORY;
         goto Done;
     }
 
+#pragma warning(push)
+#pragma warning(disable : 28145) /* The opaque MDL structure should not be modified by a driver except for
+                                    MDL_PAGES_LOCKED and MDL_MAPPING_CAN_FAIL. */
+    ring_descriptor->memory_descriptor_list->MdlFlags |= MDL_PAGES_LOCKED;
+#pragma warning(pop)
+
     memcpy(
         MmGetMdlPfnArray(ring_descriptor->memory_descriptor_list),
         MmGetMdlPfnArray(source_mdl),
@@ -226,7 +228,12 @@ ebpf_allocate_ring_buffer_memory(size_t length)
         sizeof(PFN_NUMBER) * requested_page_count);
 
     ring_descriptor->base_address = MmMapLockedPagesSpecifyCache(
-        ring_descriptor->memory_descriptor_list, KernelMode, MmCached, NULL, FALSE, NormalPagePriority);
+        ring_descriptor->memory_descriptor_list,
+        KernelMode,
+        MmCached,
+        NULL,
+        FALSE,
+        NormalPagePriority | MdlMappingNoExecute);
     if (!ring_descriptor->base_address) {
         EBPF_LOG_NTSTATUS_API_FAILURE(EBPF_TRACELOG_KEYWORD_BASE, MmMapLockedPagesSpecifyCache, STATUS_NO_MEMORY);
         status = STATUS_NO_MEMORY;