fix(metadata): exit from find() if we found a non-directory inode

Author: mhx

src/dwarfs/metadata_v2.cpp

@@ -541,6 +541,7 @@ class metadata_ final : public metadata_v2::impl {
 
   directory_view make_directory_view(inode_view iv) const {
     // TODO: revisit: is this the way to do it?
+    DWARFS_CHECK(iv.is_directory(), "not a directory");
     return directory_view(iv.inode_num(), &global_);
   }
 
@@ -1257,6 +1258,10 @@ metadata_<LoggerPolicy>::find(const char* path) const {
     const char* next = ::strchr(path, '/');
     size_t clen = next ? next - path : ::strlen(path); // Flawfinder: ignore
 
+    if (!iv->is_directory()) {
+      return std::nullopt;
+    }
+
     iv = find(make_directory_view(*iv), std::string_view(path, clen));
 
     if (!iv) {
@@ -1280,6 +1285,10 @@ metadata_<LoggerPolicy>::find(int inode, const char* name) const {
   auto iv = get_entry(inode);
 
   if (iv) {
+    if (!iv->is_directory()) {
+      return std::nullopt;
+    }
+
     iv = find(make_directory_view(*iv), std::string_view(name));
   }
 

test/dwarfs.cpp

@@ -982,3 +982,27 @@ TEST(section_index_regression, github183) {
   EXPECT_THROW(filesystem_v2::identify(lgr, mm, idss, 3),
                dwarfs::runtime_error);
 }
+
+TEST(filesystem, find_by_path) {
+  std::ostringstream logss;
+  stream_logger lgr(logss); // TODO: mock
+  lgr.set_policy<prod_logger_policy>();
+
+  auto input = test::os_access_mock::create_test_instance();
+  auto fsimage = build_dwarfs(lgr, input, "null");
+  auto mm = std::make_shared<test::mmap_mock>(std::move(fsimage));
+
+  filesystem_v2 fs(lgr, mm);
+
+  std::vector<std::string> paths;
+  fs.walk([&](auto e) { paths.emplace_back(e.unix_path()); });
+
+  EXPECT_GT(paths.size(), 10);
+
+  for (auto const& p : paths) {
+    auto iv = fs.find(p.c_str());
+    ASSERT_TRUE(iv) << p;
+    EXPECT_FALSE(fs.find(iv->inode_num(), "desktop.ini")) << p;
+    EXPECT_FALSE(fs.find((p + "/desktop.ini").c_str())) << p;
+  }
+}