Commit f6eb5daa authored by Andrew Ng's avatar Andrew Ng
Browse files

[Support] Fix Windows directory_iterator_construct out of bounds 

Fix incorrect use of the size of Path when accessing PathUTF16, as the
UTF-16 path can be shorter. Added unit test for coverage of this test
case.

Thanks to Ding Fei (danix800) for the code fix, see
https://reviews.llvm.org/D83321.

Differential Revision: https://reviews.llvm.org/D83689
parent f782d9c7

llvm/lib/Support/Windows/Path.inc

+3 −3
Original line number Diff line number Diff line
@@ -957,9 +957,9 @@ std::error_code detail::directory_iterator_construct(detail::DirIterState &IT, 
    return EC;



  // Convert path to the format that Windows is happy with.

  if (PathUTF16.size() > 0 &&

      !is_separator(PathUTF16[Path.size() - 1]) &&

      PathUTF16[Path.size() - 1] != L':') {

  size_t PathUTF16Len = PathUTF16.size();

  if (PathUTF16Len > 0 && !is_separator(PathUTF16[PathUTF16Len - 1]) &&

      PathUTF16[PathUTF16Len - 1] != L':') {

    PathUTF16.push_back(L'\\');

    PathUTF16.push_back(L'*');

  } else {

llvm/unittests/Support/Path.cpp

+33 −0
Original line number Diff line number Diff line
@@ -1149,6 +1149,39 @@ TEST_F(FileSystemTest, BrokenSymlinkDirectoryIteration) { 
}

#endif



#ifdef _WIN32

TEST_F(FileSystemTest, UTF8ToUTF16DirectoryIteration) {

  // The Windows filesystem support uses UTF-16 and converts paths from the

  // input UTF-8. The UTF-16 equivalent of the input path can be shorter in

  // length.



  // This test relies on TestDirectory not being so long such that MAX_PATH

  // would be exceeded (see widenPath). If that were the case, the UTF-16

  // path is likely to be longer than the input.

  const char *Pi = "\xcf\x80"; // UTF-8 lower case pi.

  std::string RootDir = (TestDirectory + "/" + Pi).str();



  // Create test directories.

  ASSERT_NO_ERROR(fs::create_directories(Twine(RootDir) + "/a"));

  ASSERT_NO_ERROR(fs::create_directories(Twine(RootDir) + "/b"));



  std::error_code EC;

  unsigned Count = 0;

  for (fs::directory_iterator I(Twine(RootDir), EC), E; I != E;

       I.increment(EC)) {

    ASSERT_NO_ERROR(EC);

    StringRef DirName = path::filename(I->path());

    EXPECT_TRUE(DirName == "a" || DirName == "b");

    ++Count;

  }

  EXPECT_EQ(Count, 2U);



  ASSERT_NO_ERROR(fs::remove(Twine(RootDir) + "/a"));

  ASSERT_NO_ERROR(fs::remove(Twine(RootDir) + "/b"));

  ASSERT_NO_ERROR(fs::remove(Twine(RootDir)));

}

#endif



TEST_F(FileSystemTest, Remove) {

  SmallString<64> BaseDir;

  SmallString<64> Paths[4];