From b35617de37870756bdb0e00ffc0a42441e56eefa Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 25 Jul 2022 10:27:43 -0400 Subject: Process session_preload_libraries within InitPostgres's transaction. Previously we did this after InitPostgres, at a somewhat randomly chosen place within PostgresMain. However, since commit a0ffa885e doing this outside a transaction can cause a crash, if we need to check permissions while replacing a placeholder GUC. (Besides which, a preloaded library could itself want to do database access within _PG_init.) To avoid needing an additional transaction start/end in every session, move the process_session_preload_libraries call to within InitPostgres's transaction. That requires teaching the code not to call it when InitPostgres is called from somewhere other than PostgresMain, since we don't want session_preload_libraries to affect background workers. The most future-proof solution here seems to be to add an additional flag parameter to InitPostgres; fortunately, we're not yet very worried about API stability for v15. Doing this also exposed the fact that we're currently honoring session_preload_libraries in walsenders, even those not connected to any database. This seems, at minimum, a POLA violation: walsenders are not interactive sessions. Let's stop doing that. (All these comments also apply to local_preload_libraries, of course.) Per report from Gurjeet Singh (thanks also to Nathan Bossart and Kyotaro Horiguchi for review). Backpatch to v15 where a0ffa885e came in. Discussion: https://postgr.es/m/CABwTF4VEpwTHhRQ+q5MiC5ucngN-whN-PdcKeufX7eLSoAfbZA@mail.gmail.com --- src/backend/bootstrap/bootstrap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'src/backend/bootstrap') diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c index 088556ab54c..58752368e7e 100644 --- a/src/backend/bootstrap/bootstrap.c +++ b/src/backend/bootstrap/bootstrap.c @@ -354,7 +354,7 @@ BootstrapModeMain(int argc, char *argv[], bool check_only) if (pg_link_canary_is_frontend()) elog(ERROR, "backend is incorrectly linked to frontend functions"); - InitPostgres(NULL, InvalidOid, NULL, InvalidOid, NULL, false); + InitPostgres(NULL, InvalidOid, NULL, InvalidOid, false, false, NULL); /* Initialize stuff for bootstrap-file processing */ for (i = 0; i < MAXATTR; i++) -- cgit v1.2.3