errors: provide defaults for unmapped uv errors

libuv does not map 100% of errors. When an unmapped error is
encountered, the Map returns undefined, which is then
unsuccessfully destructured, causing an exception. This commit
adds a default value in the event of an unmapped error.

PR-URL: https://github.com/nodejs/node/pull/29288
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index cf97a76b36..56c7a3bdbe 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -327,6 +327,8 @@ function lazyUv() {
   return uvBinding;
 }
 
+const uvUnmappedError = ['UNKNOWN', 'unknown error'];
+
 function uvErrmapGet(name) {
   uvBinding = lazyUv();
   if (!uvBinding.errmap) {
@@ -346,7 +348,7 @@ function uvErrmapGet(name) {
  * @returns {Error}
  */
 function uvException(ctx) {
-  const [ code, uvmsg ] = uvErrmapGet(ctx.errno);
+  const [ code, uvmsg ] = uvErrmapGet(ctx.errno) || uvUnmappedError;
   let message = `${code}: ${ctx.message || uvmsg}, ${ctx.syscall}`;
 
   let path;
@@ -404,7 +406,7 @@ function uvException(ctx) {
  * @returns {Error}
  */
 function uvExceptionWithHostPort(err, syscall, address, port) {
-  const [ code, uvmsg ] = uvErrmapGet(err);
+  const [ code, uvmsg ] = uvErrmapGet(err) || uvUnmappedError;
   const message = `${syscall} ${code}: ${uvmsg}`;
   let details = '';