From c2760bf3db292fb55b6448f22eaeee38656083b5 Mon Sep 17 00:00:00 2001 From: Nathan Bossart Date: Fri, 27 May 2022 09:48:51 -0700 Subject: [PATCH v4 1/2] Properly handle NULL short descriptions for custom variables. If a NULL short description is specified in one of the DefineCustomXXXVariable functions, SHOW ALL will segfault. This change teaches SHOW ALL to properly handle NULL short descriptions. Back-patch to all supported versions. Reported by: Steve Chavez Author: Steve Chavez Reviewed by: Nathan Bossart, Michael Paquier, Andred Freund, Tom Lane Discussion: https://postgr.es/m/CAGRrpzY6hO-Kmykna_XvsTv8P2DshGiU6G3j8yGao4mk0CqjHA%40mail.gmail.com --- src/backend/utils/misc/guc.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index 8e9b71375c..55d41ae7d6 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -9780,7 +9780,16 @@ ShowAllGUCConfig(DestReceiver *dest) isnull[1] = true; } - values[2] = PointerGetDatum(cstring_to_text(conf->short_desc)); + if (conf->short_desc) + { + values[2] = PointerGetDatum(cstring_to_text(conf->short_desc)); + isnull[2] = false; + } + else + { + values[2] = PointerGetDatum(NULL); + isnull[2] = true; + } /* send it to dest */ do_tup_output(tstate, values, isnull); @@ -9792,7 +9801,8 @@ ShowAllGUCConfig(DestReceiver *dest) pfree(setting); pfree(DatumGetPointer(values[1])); } - pfree(DatumGetPointer(values[2])); + if (conf->short_desc) + pfree(DatumGetPointer(values[2])); } end_tup_output(tstate); @@ -10002,7 +10012,7 @@ GetConfigOptionByNum(int varnum, const char **values, bool *noshow) values[3] = _(config_group_names[conf->group]); /* short_desc */ - values[4] = _(conf->short_desc); + values[4] = conf->short_desc != NULL ? _(conf->short_desc) : NULL; /* extra_desc */ values[5] = conf->long_desc != NULL ? _(conf->long_desc) : NULL; -- 2.25.1