From: David Rowley Date: Tue, 13 Jul 2021 01:32:10 +0000 (+1200) Subject: Robustify tuplesort's free_sort_tuple function X-Git-Tag: REL9_6_23~27 X-Git-Url: http://git.postgresql.org/gitweb/?a=commitdiff_plain;h=d0e44bae4923cebe08fd03f8ac6cb42757eec480;p=postgresql.git Robustify tuplesort's free_sort_tuple function 41469253e went to the trouble of removing a theoretical bug from free_sort_tuple by checking if the tuple was NULL before freeing it. Let's make this a little more robust by also setting the tuple to NULL so that should we be called again we won't end up doing a pfree on the already pfree'd tuple. Per advice from Tom Lane. Discussion: https://postgr.es/m/3188192.1626136953@sss.pgh.pa.us Backpatch-through: 9.6, same as 41469253e --- diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c index 015c197a77f..d1c29b2f043 100644 --- a/src/backend/utils/sort/tuplesort.c +++ b/src/backend/utils/sort/tuplesort.c @@ -4775,6 +4775,7 @@ writetup_datum(Tuplesortstate *state, int tapenum, SortTuple *stup) { FREEMEM(state, GetMemoryChunkSpace(stup->tuple)); pfree(stup->tuple); + stup->tuple = NULL; } }