rollup merge of #22186: GuillaumeGomez/fix-fs

Fixes issue #22174.

Author: alexcrichton

src/libstd/sys/unix/fs2.rs

@@ -159,7 +159,9 @@ impl OpenOptions {
             flags: 0,
             read: false,
             write: false,
-            mode: libc::S_IRUSR | libc::S_IWUSR,
+            mode: libc::S_IRUSR | libc::S_IWUSR
+                | libc::S_IRGRP | libc::S_IWGRP
+                | libc::S_IROTH | libc::S_IWOTH,
         }
     }