process: add code validation in process.exit()

This commit validates the `code` in `process.exit([code])`.

According to the API doc, the `code` argument must be an integer value.
However, the current implementation accepts various types of values and
internally converts them into integer values. Also, the actual
meaningful code range is 0 - 255, but it doesn't validate the range.

Signed-off-by: Daeyeon Jeong [email protected]

doc/api/process.md

@@ -1716,7 +1716,7 @@ that started the Node.js process. Symbolic links, if any, are resolved.
 added: v0.1.13
 -->
 
-* `code` {integer} The exit code. **Default:** `0`.
+* `code` {integer} The exit code in the range `0` – `255`. **Default:** `0`.
 
 The `process.exit()` method instructs Node.js to terminate the process
 synchronously with an exit status of `code`. If `code` is omitted, exit uses

lib/internal/process/per_thread.js

@@ -43,6 +43,7 @@ const {
 const format = require('internal/util/inspect').format;
 const {
   validateArray,
+  validateInteger,
   validateNumber,
   validateObject,
 } = require('internal/validators');
@@ -181,8 +182,10 @@ function wrapProcessMethods(binding) {
   function exit(code) {
     process.off('exit', handleProcessExit);
 
-    if (code || code === 0)
+    if (code !== null && code !== undefined) {
+      validateInteger(code, 'code', 0, 255);
       process.exitCode = code;
+    }
 
     if (!process._exiting) {
       process._exiting = true;

test/fixtures/exit.js

@@ -19,4 +19,9 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-process.exit(process.argv[2] || 1);
+let code;
+if (process.argv[2] !== undefined) {
+  code = parseInt(process.argv[2]);
+}
+
+process.exit(code ?? 1);

test/parallel/test-process-exit-code-validation.js

@@ -0,0 +1,50 @@
+'use strict';
+
+require('../common');
+const { strictEqual } = require('node:assert');
+
+const isParent = () => process.argv[2] === undefined;
+const invalid_type_samples = ['', '0', {}, [], true, false];
+const out_of_range_samples = [-1, 256];
+const args = [...invalid_type_samples, ...out_of_range_samples];
+
+if (isParent()) {
+  const { spawn } = require('node:child_process');
+
+  // Test the samples.
+  strictEqual(
+    invalid_type_samples.every(
+      (v) => typeof v !== 'number' && v !== null && v !== undefined,
+    ),
+    true,
+  );
+
+  strictEqual(
+    out_of_range_samples.every(
+      (v) => typeof v == 'number' && (v < 0 || v > 255),
+    ),
+    true,
+  );
+
+  // Test process.exit() with the samepls.
+  const node = process.execPath;
+  const test = (arg, expectedCode) => {
+    spawn(node, [__filename, arg]).on('exit', (code) => {
+      strictEqual(
+        code,
+        expectedCode,
+        `args[${arg}] - actual: ${code}, expected: ${expectedCode}`,
+      );
+    });
+  };
+
+  for (const index of args.keys()) {
+    test(index, 1);
+  }
+} else {
+  const i = parseInt(process.argv[2]);
+  if (Number.isNaN(i)) {
+    return process.exit(100);
+  }
+  process.exit(args[i]);
+}

test/parallel/test-worker-terminate-http2-respond-with-file.js

@@ -33,7 +33,7 @@ if (isMainThread) {
     assert.strictEqual(headers[':status'], 200);
   }));
 
-  req.on('data', common.mustCall(process.exit));
+  req.on('data', common.mustCall(() => process.exit()));
   req.on('end', common.mustNotCall());
   req.end();
 }