Set GUC "is_superuser" in all processes that set AuthenticatedUserId.

It was always false in single-user mode, in autovacuum workers, and in
background workers.  This had no specifically-identified security
consequences, but non-core code or future work might make it
security-relevant.  Back-patch to v11 (all supported versions).

Jelte Fennema-Nio.  Reported by Jelte Fennema-Nio.

diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index 922f553512e697bd74d0448dc54533e61294cc6d..1f0b3175aedf2cadf6e13e6ee2fdd2fbd41c5936 100644 (file)
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -797,6 +797,14 @@ InitializeSessionUserIdStandalone(void)
    AuthenticatedUserIsSuperuser = true;
 
    SetSessionUserId(BOOTSTRAP_SUPERUSERID, true);
+
+   /*
+    * XXX This should set SetConfigOption("session_authorization"), too.
+    * Since we don't, C code will get NULL, and current_setting() will get an
+    * empty string.
+    */
+   SetConfigOption("is_superuser", "on",
+                   PGC_INTERNAL, PGC_S_DYNAMIC_DEFAULT);
 }