Switches to using NtAllocateVirtualMemory.

XboxDev · Sep 13, 2021 · 7091a3d · 7091a3d
1 parent 12f8054
commit 7091a3d
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Showing 3 changed files with 40 additions and 93 deletions.
diff --git a/lib/winapi/filemanip.c b/lib/winapi/filemanip.c
@@ -1,7 +1,6 @@
 #include <fileapi.h>
 #include <winbase.h>
 #include <winerror.h>
-#include <winioctl.h>
 #include <assert.h>
 #include <ctype.h>
 #include <stdbool.h>
@@ -242,50 +241,8 @@ BOOL MoveFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName)
     }
 }
 
-// Determines if the two given handles refer to the same underlying file.
-static BOOL TestSameFile(HANDLE hFirst, HANDLE hSecond) {
-  NTSTATUS status;
-  IO_STATUS_BLOCK ioStatusBlock;
-  FILE_OBJECTID_BUFFER firstObjectId, secondObjectId;
-
-  status = NtFsControlFile(
-      hFirst,
-      NULL,
-      NULL,
-      NULL,
-      &ioStatusBlock,
-      FSCTL_GET_OBJECT_ID,
-      NULL,
-      0,
-      &firstObjectId,
-      sizeof(firstObjectId));
-  if (!NT_SUCCESS(status)) {
-    SetLastError(RtlNtStatusToDosError(status));
-    return FALSE;
-  }
-
-  status = NtFsControlFile(
-      hSecond,
-      NULL,
-      NULL,
-      NULL,
-      &ioStatusBlock,
-      FSCTL_GET_OBJECT_ID,
-      NULL,
-      0,
-      &secondObjectId,
-      sizeof(secondObjectId));
-  if (!NT_SUCCESS(status)) {
-    SetLastError(RtlNtStatusToDosError(status));
-    return FALSE;
-  }
-
-  return !memcmp(&firstObjectId.ObjectId, &secondObjectId.ObjectId, sizeof(firstObjectId.ObjectId));
-}
-
 BOOL CopyFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, BOOL bFailIfExists)
 {
-    static const DWORD readBufferSize = 0x10000;
     NTSTATUS status;
     HANDLE sourceHandle;
     HANDLE targetHandle = INVALID_HANDLE_VALUE;
@@ -294,7 +251,8 @@ BOOL CopyFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, BOOL bFailIfE
     OBJECT_ATTRIBUTES objectAttributes;
     IO_STATUS_BLOCK ioStatusBlock;
     FILE_NETWORK_OPEN_INFORMATION networkOpenInformation;
-    LPVOID readBuffer;
+    LPVOID readBuffer = NULL;
+    SIZE_T readBufferRegionSize = 0x1000;
     DWORD bytesRead;
 
     RtlInitAnsiString(&sourcePath, lpExistingFileName);
@@ -312,21 +270,12 @@ BOOL CopyFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, BOOL bFailIfE
         return FALSE;
     }
 
-    // Fail overwriting the file if the target == the source. This is
-    // intentionally done after the check for existence of the source
-    // to set the most appropriate LastError value.
-    if (!strcmp(lpExistingFileName, lpNewFileName)) {
-      NtClose(sourceHandle);
-      SetLastError(ERROR_SHARING_VIOLATION);
-      return FALSE;
-    }
-
     status = NtQueryInformationFile(
-            sourceHandle,
-            &ioStatusBlock,
-            &networkOpenInformation,
-            sizeof(networkOpenInformation),
-            FileNetworkOpenInformation);
+        sourceHandle,
+        &ioStatusBlock,
+        &networkOpenInformation,
+        sizeof(networkOpenInformation),
+        FileNetworkOpenInformation);
     if (!NT_SUCCESS(status)) {
         DWORD lastError = RtlNtStatusToDosError(status);
         SetLastError(lastError);
@@ -336,35 +285,52 @@ BOOL CopyFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, BOOL bFailIfE
     RtlInitAnsiString(&targetPath, lpNewFileName);
     InitializeObjectAttributes(&objectAttributes, &targetPath, OBJ_CASE_INSENSITIVE, ObDosDevicesDirectory(), NULL);
 
+    // Fail overwriting the file if the target == the source. This is
+    // intentionally done after the check for existence of the source
+    // to set the most appropriate LastError value.
+    //
+    // NOTE: FATX does not have ".." entries in directory tables, so it is not
+    // possible to overlap a file via "subdir/../file".
+    if (!strcmp(lpExistingFileName, lpNewFileName)) {
+      NtClose(sourceHandle);
+      SetLastError(ERROR_SHARING_VIOLATION);
+      return FALSE;
+    }
+
     status = NtCreateFile(
-            &targetHandle,  // FileHandle
-            FILE_GENERIC_WRITE,   // DesiredAccess
-            &objectAttributes, // ObjectAttributes
-            &ioStatusBlock,   // IoStatusBlock
-            &networkOpenInformation.AllocationSize,  // AllocationSize
-            networkOpenInformation.FileAttributes,  // FileAttributes
-            FILE_SHARE_READ | FILE_SHARE_WRITE,  // ShareAccess
-            bFailIfExists ? FILE_CREATE : FILE_SUPERSEDE,  // CreateDisposition
-            FILE_SYNCHRONOUS_IO_NONALERT | FILE_OPEN_FOR_BACKUP_INTENT);  // CreateOptions
+            &targetHandle,
+            FILE_GENERIC_WRITE,
+            &objectAttributes,
+            &ioStatusBlock,
+            &networkOpenInformation.AllocationSize,
+            networkOpenInformation.FileAttributes,
+            FILE_SHARE_READ | FILE_SHARE_WRITE,
+            bFailIfExists ? FILE_CREATE : FILE_SUPERSEDE,
+            FILE_SYNCHRONOUS_IO_NONALERT | FILE_OPEN_FOR_BACKUP_INTENT);
     if (!NT_SUCCESS(status)) {
         NtClose(sourceHandle);
         DWORD lastError = RtlNtStatusToDosError(status);
         SetLastError(lastError);
         return FALSE;
     }
 
-    readBuffer = MmAllocateContiguousMemory(readBufferSize);
-    if (!readBuffer) {
+    status = NtAllocateVirtualMemory(&readBuffer,
+                                      0,
+                                      &readBufferRegionSize,
+                                      MEM_RESERVE | MEM_COMMIT,
+                                      PAGE_READWRITE);
+    if (!NT_SUCCESS(status)) {
         NtClose(sourceHandle);
         NtClose(targetHandle);
-        SetLastError(ERROR_NOT_ENOUGH_MEMORY);
+        DWORD lastError = RtlNtStatusToDosError(status);
+        SetLastError(lastError);
         return FALSE;
     }
 
     while (TRUE) {
         const BYTE *bufferPos = readBuffer;
-        if (!ReadFile(sourceHandle, readBuffer, readBufferSize, &bytesRead, NULL)) {
-            MmFreeContiguousMemory(readBuffer);
+        if (!ReadFile(sourceHandle, readBuffer, readBufferRegionSize, &bytesRead, NULL)) {
+            NtFreeVirtualMemory(&readBuffer, &readBufferRegionSize, MEM_RELEASE);
             NtClose(sourceHandle);
             NtClose(targetHandle);
             return FALSE;
@@ -377,7 +343,7 @@ BOOL CopyFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, BOOL bFailIfE
         while (bytesRead > 0) {
             DWORD bytesWritten = 0;
             if (!WriteFile(targetHandle, bufferPos, bytesRead, &bytesWritten, NULL)) {
-                MmFreeContiguousMemory(readBuffer);
+                NtFreeVirtualMemory(&readBuffer, &readBufferRegionSize, MEM_RELEASE);
                 NtClose(sourceHandle);
                 NtClose(targetHandle);
                 return FALSE;
@@ -387,7 +353,7 @@ BOOL CopyFileA (LPCTSTR lpExistingFileName, LPCTSTR lpNewFileName, BOOL bFailIfE
         }
     }
 
-    MmFreeContiguousMemory(readBuffer);
+    NtFreeVirtualMemory(&readBuffer, &readBufferRegionSize, MEM_RELEASE);
 
     status = NtClose(sourceHandle);
     if (!NT_SUCCESS(status)) {

diff --git a/lib/winapi/winioctl.h b/lib/winapi/winioctl.h
diff --git a/lib/xboxkrnl/xboxkrnl.h b/lib/xboxkrnl/xboxkrnl.h
@@ -2861,7 +2861,6 @@ XBAPI NTSTATUS NTAPI NtOpenDirectoryObject
 
 #define FILE_DEVICE_FILE_SYSTEM 0x00000009
 #define FSCTL_DISMOUNT_VOLUME CTL_CODE(FILE_DEVICE_FILE_SYSTEM, 8, METHOD_BUFFERED, FILE_ANY_ACCESS)
-#define FSCTL_GET_OBJECT_ID CTL_CODE(FILE_DEVICE_FILE_SYSTEM, 39, METHOD_BUFFERED, FILE_ANY_ACCESS)
 
 XBAPI NTSTATUS NTAPI NtFsControlFile
 (