[PATCH v17 0/2] MR4822: ntdll: Fix: Use pagesize alignment if MEM_REPLACE_PLACEHOLDER is set in flags of NtMapViewOfSection(Ex)

[Felix Münchhalfen (＠jfmu)]

I had a bugreport here: https://bugs.winehq.org/show_bug.cgi?id=56161

This pull req fixes the bug that programs that do VirtualAlloc(placeholder)/VirtualFree(keep placeholder)/MapViewOfFile3(replace placeholder), do not run. Like the dotnet pe loader in .net 7 for example.

It was not clear to me at first, because i didnt notice it on msdn, but the way that Dmitry Timoshkov "hacked" it in https://bugs.winehq.org/show_bug.cgi?id=56122 is actually (nearly) how it is supposed to happen according to msdn.

From here: https://learn.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-m... ![image](/uploads/58614927d38c15d4c23517aa5dc09d77/image.png)

So thanks to Dmitry Timoshkov. If you are interested you could also look into the thing i mentioned in the bug report, that MapViewOfFile3 doesn't round down to 64k, but, i don't think this is a serious problem yet.

Edit: I found out that under windows, the alignment constraint is not fully lifted but, it is only required to be pagesize aligned if MEM_REPLACE_PLACEHOLDER is present in the flags.

To clarify why i want this in wine. The PE Loader of .net (see here https://github.com/dotnet/runtime/blob/f21dc6c3dceb6ea76bef73e2a026c770aaed3...) does align with page size. Not with 64k. This breaks a .net 7 app during load up, that will execute otherwise just execute fine.

--
  v17: kernelbase: Added a test for MapViewOfFile3 with MEM_REPLACE_PLACEHOLDER

https://gitlab.winehq.org/wine/wine/-/merge_requests/4822

[PATCH v17 1/2] ntdll: Fix: Use pagesize alignment if MEM_REPLACE_PLACEHOLDER is set in flags of NtMapViewOfSection(Ex)

[Felix Münchhalfen]

From: Felix Münchhalfen

---
 dlls/ntdll/unix/virtual.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/dlls/ntdll/unix/virtual.c b/dlls/ntdll/unix/virtual.c
index abe1b4dc4ec..2a53f56879e 100644
--- a/dlls/ntdll/unix/virtual.c
+++ b/dlls/ntdll/unix/virtual.c
@@ -5466,6 +5466,9 @@ NTSTATUS WINAPI NtMapViewOfSection( HANDLE handle, HANDLE process, PVOID *addr_p
     }
 #endif

+    if (alloc_type & MEM_REPLACE_PLACEHOLDER)
+        mask = page_mask;
+
     if ((offset.u.LowPart & mask) || (*addr_ptr && ((UINT_PTR)*addr_ptr & mask)))
         return STATUS_MAPPED_ALIGNMENT;

@@ -5535,6 +5538,9 @@ NTSTATUS WINAPI NtMapViewOfSectionEx( HANDLE handle, HANDLE process, PVOID *addr
     }
 #endif

+    if (alloc_type & MEM_REPLACE_PLACEHOLDER)
+        mask = page_mask;
+
     if ((offset.u.LowPart & mask) || (*addr_ptr && ((UINT_PTR)*addr_ptr & mask)))
         return STATUS_MAPPED_ALIGNMENT;

[PATCH v17 2/2] kernelbase: Added a test for MapViewOfFile3 with MEM_REPLACE_PLACEHOLDER

[Felix Münchhalfen]

From: Felix Münchhalfen

---
 dlls/kernelbase/tests/process.c | 83 +++++++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)

diff --git a/dlls/kernelbase/tests/process.c b/dlls/kernelbase/tests/process.c
index 88a527c45d5..52a14041cee 100644
--- a/dlls/kernelbase/tests/process.c
+++ b/dlls/kernelbase/tests/process.c
@@ -106,6 +106,12 @@ static void test_MapViewOfFile3(void)
     HANDLE file, mapping;
     void *ptr;
     BOOL ret;
+    SYSTEM_INFO system_info;
+    DWORD error;
+    size_t file_size = 1024UL*1024; /* 1M */
+    void *allocation;
+    void *map_start, *map_end, *map_start_offset;
+    void *view;

if (!pMapViewOfFile3)
     {
@@ -132,6 +138,83 @@ static void test_MapViewOfFile3(void)
     CloseHandle( file );
     ret = DeleteFileA( testfile );
     ok(ret, "Failed to delete a test file.\n");
+
+    /* Tests for using MapViewOfFile3 together with MEM_RESERVE_PLACEHOLDER/MEM_REPLACE_PLACEHOLDER */
+    /* like self pe-loading programs do (e.g. .net pe-loader). */
+    /* With MEM_REPLACE_PLACEHOLDER, MapViewOfFile3/NtMapViewOfSection(Ex) shall relax alignment from 64k to pagesize */
+    GetSystemInfo(&system_info);
+    mapping = CreateFileMappingA(NULL, NULL, PAGE_READWRITE, 0, (DWORD)file_size, NULL);
+    ok(mapping != NULL, "CreateFileMapping did not return a handle %lu\n", GetLastError());
+
+    allocation = pVirtualAlloc2(GetCurrentProcess(), NULL, file_size,
+                                MEM_RESERVE | MEM_RESERVE_PLACEHOLDER, PAGE_NOACCESS, NULL, 0);
+    ok(allocation != NULL, "VirtualAlloc2 returned NULL %lu\n", GetLastError());
+
+    map_start = (void*)(((ULONG_PTR)allocation + system_info.dwPageSize) & ~(system_info.dwPageSize-1));
+    map_end = (void*)((ULONG_PTR)map_start + system_info.dwPageSize);
+    ret = VirtualFree(map_start, system_info.dwPageSize, MEM_RELEASE | MEM_PRESERVE_PLACEHOLDER);
+    ok(ret, "VirtualFree failed to split the placeholder %lu\n", GetLastError());
+
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_start, system_info.dwPageSize,
+                           system_info.dwPageSize, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, NULL, 0);
+    ok(view != NULL, "MapViewOfFile3 did not map the file mapping %lu\n", GetLastError());
+
+    ret = UnmapViewOfFile(view);
+    ok(ret, "UnmapViewOfFile failed %lu\n", GetLastError());
+
+    map_start_offset = (void*)((ULONG_PTR)map_start - 1);
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_start_offset, system_info.dwPageSize,
+                           system_info.dwPageSize, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, NULL, 0);
+    ok(view == NULL, "MapViewOfFile3 did map the file mapping, though baseaddr was not pagesize aligned\n");
+    error = GetLastError();
+    ok(error == ERROR_MAPPED_ALIGNMENT, "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n",
+       ERROR_MAPPED_ALIGNMENT, error);
+
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_start, system_info.dwPageSize-1,
+                           system_info.dwPageSize, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, NULL, 0);
+    ok(view == NULL, "MapViewOfFile3 did map the FileMapping, though offset was not pagesize aligned\n");
+    error = GetLastError();
+    ok(error == ERROR_MAPPED_ALIGNMENT,
+       "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n",
+       ERROR_MAPPED_ALIGNMENT, error);
+
+    ret = VirtualFree(allocation, 0, MEM_RELEASE);
+    ok(ret, "VirtualFree of first remaining region failed\n");
+
+    ret = VirtualFree(map_end, 0, MEM_RELEASE);
+    ok(ret, "VirtualFree of remaining region failed\n");
+
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_end, system_info.dwPageSize, 0, 0, PAGE_READWRITE, NULL, 0);
+    ok(view == NULL, "MapViewOfFile3 did map the file mapping, though baseaddr was not 64k aligned\n");
+    error = GetLastError();
+    ok(error == ERROR_MAPPED_ALIGNMENT,
+       "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n",
+       ERROR_MAPPED_ALIGNMENT, error);
+
+    map_start = (void*)(((ULONG_PTR)allocation + system_info.dwAllocationGranularity)&~(system_info.dwAllocationGranularity-1));
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_end,
+                           system_info.dwPageSize, system_info.dwPageSize, 0, PAGE_READWRITE, NULL, 0);
+    ok(view == NULL, "MapViewOfFile3 did map the file mapping, though offset was not 64k aligned\n");
+    error = GetLastError();
+    ok(error == ERROR_MAPPED_ALIGNMENT,
+       "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n",
+       ERROR_MAPPED_ALIGNMENT, error);
+
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_start, 0,
+                           system_info.dwPageSize, 0, PAGE_READWRITE, NULL, 0);
+    ok(view != NULL, "MapViewOfFile3 failed though both baseaddr and offset were 64k aligned %lu\n", GetLastError());
+
+    ret = UnmapViewOfFile(view);
+    ok(ret, "UnmapViewOfFile failed %lu\n", GetLastError());
+
+    view = pMapViewOfFile3(mapping, GetCurrentProcess(), map_start,
+                           4*system_info.dwAllocationGranularity, system_info.dwPageSize, 0, PAGE_READWRITE, NULL, 0);
+    ok(view != NULL, "MapViewOfFile3 failed though both baseaddr and offset were 64k aligned %lu\n", GetLastError());
+
+    ret = UnmapViewOfFile(view);
+    ok(ret, "UnmapViewOfFile failed %lu\n", GetLastError());
+
+    ok(CloseHandle(mapping), "CloseHandle failed on mapping\n");
 }

#define check_region_size(p, s) check_region_size_(p, s, __LINE__)