[PATCH v13 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.

--
  v13: kernelbase: Added a test for MapViewOfFile3 with MEM_REPLACE_PLACEHOLDER

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

[PATCH v13 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 v13 2/2] kernelbase: Added a test for MapViewOfFile3 with MEM_REPLACE_PLACEHOLDER

[Felix Münchhalfen]

From: Felix Münchhalfen

---
 dlls/kernelbase/tests/process.c | 71 +++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/dlls/kernelbase/tests/process.c b/dlls/kernelbase/tests/process.c
index 88a527c45d5..fcfe250c895 100644
--- a/dlls/kernelbase/tests/process.c
+++ b/dlls/kernelbase/tests/process.c
@@ -38,6 +38,7 @@ static LPVOID (WINAPI *pMapViewOfFile3)(HANDLE, HANDLE, PVOID, ULONG64 offset, S
 static LPVOID (WINAPI *pVirtualAlloc2)(HANDLE, void *, SIZE_T, DWORD, DWORD, MEM_EXTENDED_PARAMETER *, ULONG);
 static LPVOID (WINAPI *pVirtualAlloc2FromApp)(HANDLE, void *, SIZE_T, DWORD, DWORD, MEM_EXTENDED_PARAMETER *, ULONG);
 static PVOID (WINAPI *pVirtualAllocFromApp)(PVOID, SIZE_T, DWORD, DWORD);
+static BOOL (WINAPI *pVirtualFree)(LPVOID,SIZE_T,DWORD);
 static HANDLE (WINAPI *pOpenFileMappingFromApp)( ULONG, BOOL, LPCWSTR);
 static HANDLE (WINAPI *pCreateFileMappingFromApp)(HANDLE, PSECURITY_ATTRIBUTES, ULONG, ULONG64, PCWSTR);
 static LPVOID (WINAPI *pMapViewOfFileFromApp)(HANDLE, ULONG, ULONG64, SIZE_T);
@@ -106,6 +107,16 @@ static void test_MapViewOfFile3(void)
     HANDLE file, mapping;
     void *ptr;
     BOOL ret;
+    SYSTEM_INFO si;
+    DWORD dError;
+    size_t szFile = 1024UL*1024; // 1M
+    HANDLE hFileMapping;
+    PVOID pAllocation;
+    PVOID pMapStart;
+    PVOID pMapStartOff;
+    PVOID pMapEnd;
+    BOOL bVirtualFree;
+    PVOID pMappedFileView;

if (!pMapViewOfFile3)
     {
@@ -132,6 +143,65 @@ 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(&si);
+    hFileMapping = CreateFileMappingA(NULL, NULL, PAGE_READWRITE, 0, (DWORD)szFile, NULL);
+    ok(hFileMapping != NULL, "CreateFileMapping did not return a handle %lu\n", GetLastError());
+
+    pAllocation = pVirtualAlloc2(GetCurrentProcess(), NULL, szFile, MEM_RESERVE | MEM_RESERVE_PLACEHOLDER, PAGE_NOACCESS, NULL, 0);
+    ok(pAllocation != NULL, "VirtualAlloc2 returned NULL %lu\n", GetLastError());
+
+    pMapStart = (void*)(((ULONG_PTR)pAllocation + si.dwPageSize) & ~(si.dwPageSize-1)); // advance forward one pagesize + align to pagesize
+    pMapEnd = (void*)((ULONG_PTR)pMapStart + si.dwPageSize);
+    bVirtualFree = pVirtualFree(pMapStart, si.dwPageSize, MEM_RELEASE | MEM_PRESERVE_PLACEHOLDER); // split the region, keep placeholders
+    ok(bVirtualFree, "VirtualFree failed to split the placeholder %lu\n", GetLastError());
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapStart, si.dwPageSize, si.dwPageSize, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, NULL, 0);
+    // this should succeed, because pMapStart is pagesize aligned
+    ok(pMappedFileView != NULL, "MapViewOfFile3 did not map the FileMapping %lu\n", GetLastError());
+    ok(pMappedFileView == pMapStart, "MapViewOfFile did not map to the requested addr\n");
+    ok(UnmapViewOfFile( pMappedFileView ), "UnmapViewOfFile failed %lu\n", GetLastError());
+    // this should fail, because pMapStart-1 is not pagesize aligned
+    pMapStartOff = (void*)((ULONG_PTR)pMapStart - 1);
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapStartOff, si.dwPageSize, si.dwPageSize, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, NULL, 0);
+    ok(pMappedFileView == NULL, "MapViewOfFile3 did map the FileMapping, though baseaddr was not pagesize aligned\n");
+    dError = GetLastError();
+    ok(dError == ERROR_MAPPED_ALIGNMENT, "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n", ERROR_MAPPED_ALIGNMENT, dError);
+    // this should fail, because offset=si.dwPageSize-1 is not pagesize aligned
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapStart, si.dwPageSize-1, si.dwPageSize, MEM_REPLACE_PLACEHOLDER, PAGE_READWRITE, NULL, 0);
+    ok(pMappedFileView == NULL, "MapViewOfFile3 did map the FileMapping, though offset was not pagesize aligned\n");
+    dError = GetLastError();
+    ok(dError == ERROR_MAPPED_ALIGNMENT, "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n", ERROR_MAPPED_ALIGNMENT, dError);
+    // Free the space and then test mapping into the now-free space normally (without MEM_REPLACE_PLACEHOLDER)
+    bVirtualFree = pVirtualFree(pAllocation, 0, MEM_RELEASE); 
+    ok(bVirtualFree, "VirtualFree of first remaining region failed\n");
+    bVirtualFree = pVirtualFree(pMapEnd, 0, MEM_RELEASE); 
+    ok(bVirtualFree, "VirtualFree of remaining region failed\n");
+    // this should fail because we require 64k alignment for baseaddr, if MEM_REPLACE_PLACEHOLDER is not used
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapEnd, si.dwPageSize, 0, 0, PAGE_READWRITE, NULL, 0);
+    ok(pMappedFileView == NULL, "MapViewOfFile3 did map the FileMapping, though baseaddr was not 64k aligned\n");
+    dError = GetLastError();
+    ok(dError == ERROR_MAPPED_ALIGNMENT, "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n", ERROR_MAPPED_ALIGNMENT, dError);
+    // this should fail because we require 64k alignment for offset, if MEM_REPLACE_PLACEHOLDER is not used
+    pMapStart = (void*)(((ULONG_PTR)pAllocation + si.dwAllocationGranularity)&~(si.dwAllocationGranularity-1)); // align pMapStart to 64k
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapEnd, si.dwPageSize, si.dwPageSize, 0, PAGE_READWRITE, NULL, 0);
+    ok(pMappedFileView == NULL, "MapViewOfFile3 did map the FileMapping, though offset was not 64k aligned\n");
+    dError = GetLastError();
+    ok(dError == ERROR_MAPPED_ALIGNMENT, "MapViewOfFile3 did not return ERROR_MAPPED_ALIGNMENT(%u), instead it returned %lu\n", ERROR_MAPPED_ALIGNMENT, dError);
+    // this should succeed if MEM_REPLACE_PLACEHOLDER is not used, because both baseaddr and offset are 64k aligned
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapStart, 0, si.dwPageSize, 0, PAGE_READWRITE, NULL, 0);
+    ok(pMappedFileView != NULL, "MapViewOfFile3 failed though both baseaddr and offset were 64k aligned %lu\n", GetLastError());
+    ok(pMappedFileView == pMapStart, "MapViewOfFile did not map to the requested addr\n");
+    ok(UnmapViewOfFile( pMappedFileView ), "UnmapViewOfFile failed %lu\n", GetLastError());
+    // this should succeed too if MEM_REPLACE_PLACEHOLDER is not used, if offset is aligned to 64k and != 0
+    pMappedFileView = pMapViewOfFile3(hFileMapping, GetCurrentProcess(), pMapStart, 4*si.dwAllocationGranularity, si.dwPageSize, 0, PAGE_READWRITE, NULL, 0);
+    ok(pMappedFileView != NULL, "MapViewOfFile3 failed though both baseaddr and offset were 64k aligned %lu\n", GetLastError());
+    ok(pMappedFileView == pMapStart, "MapViewOfFile did not map to the requested addr\n");
+    ok(UnmapViewOfFile( pMappedFileView ), "UnmapViewOfFile failed %lu\n", GetLastError());
+    // cleanup file mapping
+    ok(CloseHandle(hFileMapping), "CloseHandle failed on hFileMapping\n");
 }

#define check_region_size(p, s) check_region_size_(p, s, __LINE__)
@@ -519,6 +589,7 @@ static void init_funcs(void)
     X(VirtualAlloc2);
     X(VirtualAlloc2FromApp);
     X(VirtualAllocFromApp);
+    X(VirtualFree);
     X(UnmapViewOfFile2);

hmod = GetModuleHandleA("ntdll.dll");