Re: User with BYPASSRLS privilege can't change password

I wrote:
> Wolfgang Walther <walther@technowledgy.de> writes:
>> CREATE USER bob BYPASSRLS;
>> SET ROLE bob;
>> ALTER USER bob PASSWORD 'x';
>> -- ERROR: must be superuser to change bypassrls attribute

> Yeah, duplicated here on HEAD.  The error message seems to think
> the command is trying to remove the BYPASSRLS privilege, which
> suggests somebody forgot to copy that flag somewhere where it needs
> to be copied.  Haven't dug further than that.

It's a little more subtle than that, but not much.  Commit 491c029db
copied-and-pasted the logic used to deny non-superusers the privilege
to change anything about a superuser role.  That was certainly not the
intention, because the error message was phrased differently from the
superuser case, but that was the effect.  I propose the attached.

(Hm, looks like this behavior is undocumented, too.)

            regards, tom lane

diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 9ce9a66921..5cd479a649 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -709,8 +709,10 @@ AlterRole(AlterRoleStmt *stmt)
     roleid = authform->oid;
 
     /*
-     * To mess with a superuser you gotta be superuser; else you need
-     * createrole, or just want to change your own password
+     * To mess with a superuser or replication role in any way you gotta be
+     * superuser.  We also insist on superuser to change the BYPASSRLS
+     * property.  Otherwise, if you don't have createrole, you're only allowed
+     * to change your own password.
      */
     if (authform->rolsuper || issuper >= 0)
     {
@@ -726,7 +728,7 @@ AlterRole(AlterRoleStmt *stmt)
                     (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
                      errmsg("must be superuser to alter replication users")));
     }
-    else if (authform->rolbypassrls || bypassrls >= 0)
+    else if (bypassrls >= 0)
     {
         if (!superuser())
             ereport(ERROR,
@@ -739,7 +741,6 @@ AlterRole(AlterRoleStmt *stmt)
               createrole < 0 &&
               createdb < 0 &&
               canlogin < 0 &&
-              isreplication < 0 &&
               !dconnlimit &&
               !rolemembers &&
               !validUntil &&