From fc8c1b1ded9f21fb7e4f97cbcc4bc4d419c23b52 Mon Sep 17 00:00:00 2001
From: Jon Moss <me@jonathanmoss.me>
Date: Wed, 13 Dec 2017 17:29:03 -0500
Subject: [PATCH] fs: extract out validateOffsetLengthRead function
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PR-URL: https://github.com/nodejs/node/pull/17682
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
---
 lib/fs.js | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/lib/fs.js b/lib/fs.js
index 2a1fa8c5a3f..c1f24608de2 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -165,6 +165,21 @@ function validateFd(fd) {
   }
 }
 
+function validateOffsetLengthRead(offset, length, bufferLength) {
+  let err;
+
+  if (offset < 0 || offset >= bufferLength) {
+    err = new errors.RangeError('ERR_OUT_OF_RANGE', 'offset');
+  } else if (length < 0 || offset + length > bufferLength) {
+    err = new errors.RangeError('ERR_OUT_OF_RANGE', 'length');
+  }
+
+  if (err !== undefined) {
+    Error.captureStackTrace(err, validateOffsetLengthRead);
+    throw err;
+  }
+}
+
 // Special case of `makeCallback()` that is specific to async `*stat()` calls as
 // an optimization, since the data passed back to the callback needs to be
 // transformed anyway.
@@ -743,11 +758,7 @@ fs.read = function(fd, buffer, offset, length, position, callback) {
     });
   }
 
-  if (offset < 0 || offset >= buffer.length)
-    throw new errors.RangeError('ERR_OUT_OF_RANGE', 'offset');
-
-  if (length < 0 || offset + length > buffer.length)
-    throw new errors.RangeError('ERR_OUT_OF_RANGE', 'length');
+  validateOffsetLengthRead(offset, length, buffer.length);
 
   if (!isUint32(position))
     position = -1;
@@ -779,11 +790,7 @@ fs.readSync = function(fd, buffer, offset, length, position) {
     return 0;
   }
 
-  if (offset < 0 || offset >= buffer.length)
-    throw new errors.RangeError('ERR_OUT_OF_RANGE', 'offset');
-
-  if (length < 0 || offset + length > buffer.length)
-    throw new errors.RangeError('ERR_OUT_OF_RANGE', 'length');
+  validateOffsetLengthRead(offset, length, buffer.length);
 
   if (!isUint32(position))
     position = -1;