diff --git a/lib/config/core.js b/lib/config/core.js
index 18658842175f0..36420b3450163 100644
--- a/lib/config/core.js
+++ b/lib/config/core.js
@@ -31,10 +31,8 @@ enumerable: true })
 
 exports.validate = validate
 
-var myUid = process.env.SUDO_UID !== undefined
-  ? process.env.SUDO_UID : (process.getuid && process.getuid())
-var myGid = process.env.SUDO_GID !== undefined
-  ? process.env.SUDO_GID : (process.getgid && process.getgid())
+var myUid = process.getuid && process.getuid()
+var myGid = process.getgid && process.getgid()
 
 var loading = false
 var loadCbs = []
@@ -283,15 +281,21 @@ Conf.prototype.save = function (where, cb) {
       done(null)
     })
   } else {
-    mkdirp(path.dirname(target.path), function (er) {
+    // we don't have to use inferOwner here, because gentle-fs will
+    // mkdir with the correctly inferred ownership.  Just preserve it.
+    const dir = path.dirname(target.path)
+    mkdirp(dir, function (er) {
       if (er) return then(er)
-      fs.writeFile(target.path, data, 'utf8', function (er) {
+      fs.stat(dir, (er, st) => {
         if (er) return then(er)
-        if (where === 'user' && myUid && myGid) {
-          fs.chown(target.path, +myUid, +myGid, then)
-        } else {
-          then()
-        }
+        fs.writeFile(target.path, data, 'utf8', function (er) {
+          if (er) return then(er)
+          if (myUid === 0 && (myUid !== st.uid || myGid !== st.gid)) {
+            fs.chown(target.path, st.uid, st.gid, then)
+          } else {
+            then()
+          }
+        })
       })
     })
   }