From: David Rowley Date: Tue, 13 Jul 2021 01:27:05 +0000 (+1200) Subject: Robustify tuplesort's free_sort_tuple function X-Git-Url: http://git.postgresql.org/gitweb/-?a=commitdiff_plain;h=5bd38d2f2846c7e387d04a16c4372da0de7b1221;p=users%2Frhaas%2Fpostgres.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 27069814de..b17347b214 100644 --- a/src/backend/utils/sort/tuplesort.c +++ b/src/backend/utils/sort/tuplesort.c @@ -4777,5 +4777,6 @@ free_sort_tuple(Tuplesortstate *state, SortTuple *stup) { FREEMEM(state, GetMemoryChunkSpace(stup->tuple)); pfree(stup->tuple); + stup->tuple = NULL; } }