fs: fix promises reads with pos > 4GB

PR-URL: https://github.com/nodejs/node/pull/21148
Fixes: https://github.com/nodejs/node/issues/21121
Refs: https://github.com/nodejs/node/pull/21003
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Ujjwal Sharma <usharma1998@gmail.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/test/parallel/test-fs-promises-file-handle-read.js b/test/parallel/test-fs-promises-file-handle-read.js
index a397b0e260..621e63c075 100644
--- a/test/parallel/test-fs-promises-file-handle-read.js
+++ b/test/parallel/test-fs-promises-file-handle-read.js
@@ -8,6 +8,7 @@ const common = require('../common');
 const fs = require('fs');
 const { open } = fs.promises;
 const path = require('path');
+const fixtures = require('../common/fixtures');
 const tmpdir = require('../common/tmpdir');
 const assert = require('assert');
 const tmpDir = tmpdir.path;
@@ -40,6 +41,19 @@ async function validateEmptyRead() {
   assert.deepStrictEqual(buffer.length, readAsyncHandle.bytesRead);
 }
 
+async function validateLargeRead() {
+  // Reading beyond file length (3 in this case) should return no data.
+  // This is a test for a bug where reads > uint32 would return data
+  // from the current position in the file.
+  const filePath = fixtures.path('x.txt');
+  const fileHandle = await open(filePath, 'r');
+  const pos = 0xffffffff + 1; // max-uint32 + 1
+  const readHandle = await fileHandle.read(Buffer.alloc(1), 0, 1, pos);
+
+  assert.strictEqual(readHandle.bytesRead, 0);
+}
+
 validateRead()
   .then(validateEmptyRead)
+  .then(validateLargeRead)
   .then(common.mustCall());