[PATCH] ntdll: Map top-down if dll characteristics include DYNAMIC_BASE.

[Myah Caron]

Wine-bug: https://bugs.winehq.org/show_bug.cgi?id=44893
Wine-bug: https://bugs.winehq.org/show_bug.cgi?id=48641
Signed-off-by: Myah Caron <qsniyg(a)protonmail.com>
---
Since I don't know how to write a test for this with the wine build system, I've written one here:
https://github.com/qsniyg/wine_dll_load_test/tree/b2b64bc8d7d1589cbfeb1dbb53...

The reason for the two DLLs in the test is because I initially believed the issue was caused by
the conflict between both binkw64.dll and skse64_1_5_97.dll having a preferred imagebase of 0x180000000
(as noted by Focht).

If --dynamicbase is added to the linker options, it will allocate the DLL top-down rather than bottom-up.
This patch fixes the SKSE issue, as it requires its base address to be > 0x78000000.

 dlls/ntdll/loader.c      | 4 +++-
 dlls/ntdll/unix/loader.c | 4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/dlls/ntdll/loader.c b/dlls/ntdll/loader.c
index 8374dd97326..4d4ce3c6c6c 100644
--- a/dlls/ntdll/loader.c
+++ b/dlls/ntdll/loader.c
@@ -2230,6 +2230,7 @@ static NTSTATUS open_dll_file( UNICODE_STRING *nt_name, WINE_MODREF **pwm, void
     SIZE_T len = 0;
     NTSTATUS status;
     HANDLE handle, mapping;
+    ULONG alloc_type;

     if ((*pwm = find_fullname_module( nt_name )))
     {
@@ -2287,8 +2288,9 @@ static NTSTATUS open_dll_file( UNICODE_STRING *nt_name, WINE_MODREF **pwm, void
             *module = NULL;
         }
         NtQuerySection( mapping, SectionImageInformation, image_info, sizeof(*image_info), NULL );
+        alloc_type = (image_info->DllCharacteristics & IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE) ? MEM_TOP_DOWN : 0;
         status = NtMapViewOfSection( mapping, NtCurrentProcess(), module, 0, 0, NULL, &len,
-                                     ViewShare, 0, PAGE_EXECUTE_READ );
+                                     ViewShare, alloc_type, PAGE_EXECUTE_READ );
         if (status == STATUS_IMAGE_NOT_AT_BASE) status = STATUS_SUCCESS;
         NtClose( mapping );
     }
diff --git a/dlls/ntdll/unix/loader.c b/dlls/ntdll/unix/loader.c
index c2b6ea603e3..99ae50970de 100644
--- a/dlls/ntdll/unix/loader.c
+++ b/dlls/ntdll/unix/loader.c
@@ -1142,6 +1142,7 @@ static NTSTATUS open_dll_file( const char *name, void **module, SECTION_IMAGE_IN
     SIZE_T len = 0;
     NTSTATUS status;
     HANDLE handle, mapping;
+    ULONG alloc_type;

     if ((status = open_unix_file( &handle, name, GENERIC_READ | SYNCHRONIZE, &attr, 0,
                                   FILE_SHARE_READ | FILE_SHARE_DELETE, FILE_OPEN,
@@ -1186,8 +1187,9 @@ static NTSTATUS open_dll_file( const char *name, void **module, SECTION_IMAGE_IN
         *module = NULL;
     }
     NtQuerySection( mapping, SectionImageInformation, image_info, sizeof(*image_info), NULL );
+    alloc_type = (image_info->DllCharacteristics & IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE) ? MEM_TOP_DOWN : 0;
     status = NtMapViewOfSection( mapping, NtCurrentProcess(), module, 0, 0, NULL, &len,
-                                 ViewShare, 0, PAGE_EXECUTE_READ );
+                                 ViewShare, alloc_type, PAGE_EXECUTE_READ );
     if (status == STATUS_IMAGE_NOT_AT_BASE) status = STATUS_SUCCESS;
     NtClose( mapping );
     if (status) return status;
--
2.28.0