Merge pull request #24 from isanae/null-pointer-in-move

(WIP) Handle null pointer in MoveFileExA() and MoveFileWithProgressA()
ModOrganizer2 · Oct 20, 2019 · 4c50507 · 4c50507
2 parents 496d2f8 + fdb8fb6
commit 4c50507
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Showing 2 changed files with 26 additions and 6 deletions.
diff --git a/include/usvfs_version.h b/include/usvfs_version.h
@@ -3,7 +3,7 @@
 #define USVFS_VERSION_MAJOR 0
 #define USVFS_VERSION_MINOR 4
 #define USVFS_VERSION_BUILD 4
-#define USVFS_VERSION_REVISION 4
+#define USVFS_VERSION_REVISION 5
 
 #define USVFS_BUILD_STRING ""
 #define USVFS_BUILD_WSTRING L""

diff --git a/src/usvfs_dll/hooks/kernel32.cpp b/src/usvfs_dll/hooks/kernel32.cpp
@@ -675,11 +675,21 @@ BOOL WINAPI usvfs::hook_MoveFileExA(LPCSTR lpExistingFileName,
   HOOK_END
   HOOK_START
 
-  const auto& existingFileName = ush::string_cast<std::wstring>(lpExistingFileName);
-  const auto& newFileName = ush::string_cast<std::wstring>(lpNewFileName);
+  const std::wstring existingFileName = ush::string_cast<std::wstring>(lpExistingFileName);
+
+  // careful: lpNewFileName can be null if dwFlags is
+  // MOVEFILE_DELAY_UNTIL_REBOOT, so don't blindly cast the string and make sure
+  // the null pointer is forwarded correctly
+  std::wstring newFileNameWstring;
+  const wchar_t* newFileName = nullptr;
+
+  if (lpNewFileName) {
+    newFileNameWstring = ush::string_cast<std::wstring>(lpNewFileName);
+    newFileName = newFileNameWstring.c_str();
+  }
 
   PRE_REALCALL
-    res = MoveFileExW(existingFileName.c_str(), newFileName.c_str(), dwFlags);
+    res = MoveFileExW(existingFileName.c_str(), newFileName, dwFlags);
   POST_REALCALL
 
   HOOK_END
@@ -792,10 +802,20 @@ BOOL WINAPI usvfs::hook_MoveFileWithProgressA(LPCSTR lpExistingFileName, LPCSTR
   HOOK_START
 
   const auto& existingFileName = ush::string_cast<std::wstring>(lpExistingFileName);
-  const auto& newFileName = ush::string_cast<std::wstring>(lpNewFileName);
+
+  // careful: lpNewFileName can be null if dwFlags is
+  // MOVEFILE_DELAY_UNTIL_REBOOT, so don't blindly cast the string and make sure
+  // the null pointer is forwarded correctly
+  std::wstring newFileNameWstring;
+  const wchar_t* newFileName = nullptr;
+
+  if (lpNewFileName) {
+    newFileNameWstring = ush::string_cast<std::wstring>(lpNewFileName);
+    newFileName = newFileNameWstring.c_str();
+  }
 
   PRE_REALCALL
-    res = MoveFileWithProgressW(existingFileName.c_str(), newFileName.c_str(), lpProgressRoutine, lpData, dwFlags);
+    res = MoveFileWithProgressW(existingFileName.c_str(), newFileName, lpProgressRoutine, lpData, dwFlags);
   POST_REALCALL
 
   HOOK_END