vfs: validate ZipProvider parent directories

lib/internal/vfs/providers/ziparchive.js

@@ -329,6 +329,24 @@ class ZipProvider extends VirtualProvider {
     return false;
   }
 
+  /**
+   * Throws when an ancestor of `name` is a file. Missing ancestors are valid:
+   * ZIP archives represent directories implicitly when they contain entries
+   * beneath them.
+   * @param {string} name
+   * @param {string} syscall
+   * @param {string} path
+   */
+  #validateParentDirectories(name, syscall, path) {
+    let slash = StringPrototypeIndexOf(name, '/');
+    while (slash !== -1) {
+      if (this.#source.has(StringPrototypeSlice(name, 0, slash))) {
+        throw createENOTDIR(syscall, path);
+      }
+      slash = StringPrototypeIndexOf(name, '/', slash + 1);
+    }
+  }
+
   async open(path, flags, mode) {
     flags = normalizeFlags(flags);
     const name = normalize(path);
@@ -346,6 +364,7 @@ class ZipProvider extends VirtualProvider {
     if (!exists && (flags === 'r' || flags === 'r+')) {
       throw createENOENT('open', path);
     }
+    if (!exists) this.#validateParentDirectories(name, 'open', path);
     let initial = EMPTY_BUFFER;
     if (exists && !isWriteTruncate(flags)) {
       initial = await fileEntry.content();
@@ -369,6 +388,7 @@ class ZipProvider extends VirtualProvider {
     if (!exists && (flags === 'r' || flags === 'r+')) {
       throw createENOENT('open', path);
     }
+    if (!exists) this.#validateParentDirectories(name, 'open', path);
     let initial = EMPTY_BUFFER;
     if (exists && !isWriteTruncate(flags)) {
       initial = fileEntry.contentSync();
@@ -450,6 +470,7 @@ class ZipProvider extends VirtualProvider {
   async mkdir(path, options) {
     if (this.readonly) throw createEROFS('mkdir', path);
     const name = normalize(path);
+    this.#validateParentDirectories(name, 'mkdir', path);
     if (await this.exists(path)) {
       // `{ recursive: true }` only tolerates an existing *directory*; an
       // existing file (or any non-directory) still collides with EEXIST.
@@ -462,6 +483,7 @@ class ZipProvider extends VirtualProvider {
   mkdirSync(path, options) {
     if (this.readonly) throw createEROFS('mkdir', path);
     const name = normalize(path);
+    this.#validateParentDirectories(name, 'mkdir', path);
     if (this.existsSync(path)) {
       // `{ recursive: true }` only tolerates an existing *directory*; an
       // existing file (or any non-directory) still collides with EEXIST.
@@ -531,6 +553,7 @@ class ZipProvider extends VirtualProvider {
     const newName = normalize(newPath);
     const entry = await this.#getEntry(oldName);
     if (entry === null) throw createENOENT('rename', oldPath);
+    this.#validateParentDirectories(newName, 'rename', newPath);
     const content = await entry.content();
     await this.#source.add(newName, content, {
       mode: entry.mode || undefined,
@@ -545,6 +568,7 @@ class ZipProvider extends VirtualProvider {
     const newName = normalize(newPath);
     const entry = this.#getEntrySync(oldName);
     if (entry === null) throw createENOENT('rename', oldPath);
+    this.#validateParentDirectories(newName, 'rename', newPath);
     const content = entry.contentSync();
     this.#source.addSync(newName, content, {
       mode: entry.mode || undefined,

test/parallel/test-vfs-zip-provider.js

@@ -83,6 +83,24 @@ async function buildArchive(entries, comment) {
     assert.strictEqual(await archiveVfs.promises.readFile('/new.txt', 'utf8'), 'brand new');
     assert.strictEqual(zip.has('new.txt'), true);
 
+    // Entries cannot be created beneath a file.
+    await assert.rejects(
+      archiveVfs.promises.writeFile('/a.txt/child.txt', 'child'),
+      { code: 'ENOTDIR' },
+    );
+    await assert.rejects(
+      archiveVfs.promises.mkdir('/a.txt/child'),
+      { code: 'ENOTDIR' },
+    );
+    await assert.rejects(
+      archiveVfs.promises.rename('/new.txt', '/a.txt/renamed.txt'),
+      { code: 'ENOTDIR' },
+    );
+    assert.strictEqual(zip.has('a.txt/child.txt'), false);
+    assert.strictEqual(zip.has('a.txt/child/'), false);
+    assert.strictEqual(zip.has('a.txt/renamed.txt'), false);
+    assert.strictEqual(zip.has('new.txt'), true);
+
     // Overwriting an existing file.
     await archiveVfs.promises.writeFile('/a.txt', 'overwritten');
     assert.strictEqual(await archiveVfs.promises.readFile('/a.txt', 'utf8'), 'overwritten');
@@ -195,6 +213,24 @@ async function buildArchive(entries, comment) {
     archiveVfs.appendFileSync('/new.txt', '!');
     assert.strictEqual(archiveVfs.readFileSync('/new.txt', 'utf8'), 'brand new!');
 
+    // Entries cannot be created beneath a file.
+    assert.throws(
+      () => archiveVfs.writeFileSync('/a.txt/child.txt', 'child'),
+      { code: 'ENOTDIR' },
+    );
+    assert.throws(
+      () => archiveVfs.mkdirSync('/a.txt/child'),
+      { code: 'ENOTDIR' },
+    );
+    assert.throws(
+      () => archiveVfs.renameSync('/new.txt', '/a.txt/renamed.txt'),
+      { code: 'ENOTDIR' },
+    );
+    assert.strictEqual(zip.has('a.txt/child.txt'), false);
+    assert.strictEqual(zip.has('a.txt/child/'), false);
+    assert.strictEqual(zip.has('a.txt/renamed.txt'), false);
+    assert.strictEqual(zip.has('new.txt'), true);
+
     // mkdir/rmdir.
     archiveVfs.mkdirSync('/newdir');
     assert.strictEqual(archiveVfs.statSync('/newdir').isDirectory(), true);