From dbf23d519d6a11d3ecc1220eb38d67ece5ae52d8 Mon Sep 17 00:00:00 2001 From: John Naylor Date: Wed, 21 Jan 2026 16:44:46 +0700 Subject: [PATCH v1 2/2] Fix various cases of undefined behavior Reported-by: Alexander Lakhin Tested-by: Discussion: https://postgr.es/m/777bd201-6e3a-4da0-a922-4ea9de46a3ee@gmail.com --- contrib/pg_trgm/trgm_gist.c | 5 ++++- src/backend/access/heap/heaptoast.c | 2 +- src/backend/utils/sort/sharedtuplestore.c | 3 ++- 3 files changed, 7 insertions(+), 3 deletions(-) diff --git a/contrib/pg_trgm/trgm_gist.c b/contrib/pg_trgm/trgm_gist.c index 5c7deb103a6..b6ad13cc0a4 100644 --- a/contrib/pg_trgm/trgm_gist.c +++ b/contrib/pg_trgm/trgm_gist.c @@ -699,10 +699,13 @@ gtrgm_penalty(PG_FUNCTION_ARGS) if (ISARRKEY(newval)) { char *cache = (char *) fcinfo->flinfo->fn_extra; - TRGM *cachedVal = (TRGM *) (cache + MAXALIGN(siglen)); + TRGM *cachedVal = NULL; Size newvalsize = VARSIZE(newval); BITVECP sign; + if (cache != NULL) + cachedVal = (TRGM *) (cache + MAXALIGN(siglen)); + /* * Cache the sign data across multiple calls with the same newval. */ diff --git a/src/backend/access/heap/heaptoast.c b/src/backend/access/heap/heaptoast.c index e28fe47a449..3fb4a8d2a49 100644 --- a/src/backend/access/heap/heaptoast.c +++ b/src/backend/access/heap/heaptoast.c @@ -768,7 +768,7 @@ heap_fetch_toast_slice(Relation toastrel, Oid valueid, int32 attrsize, chcpyend = (sliceoffset + slicelength - 1) % TOAST_MAX_CHUNK_SIZE; memcpy(VARDATA(result) + - (curchunk * TOAST_MAX_CHUNK_SIZE - sliceoffset) + chcpystrt, + chcpystrt + (curchunk * TOAST_MAX_CHUNK_SIZE - sliceoffset), chunkdata + chcpystrt, (chcpyend - chcpystrt) + 1); diff --git a/src/backend/utils/sort/sharedtuplestore.c b/src/backend/utils/sort/sharedtuplestore.c index 8f35a255263..04189f708fa 100644 --- a/src/backend/utils/sort/sharedtuplestore.c +++ b/src/backend/utils/sort/sharedtuplestore.c @@ -323,7 +323,8 @@ sts_puttuple(SharedTuplestoreAccessor *accessor, void *meta_data, /* Do we have space? */ size = accessor->sts->meta_data_size + tuple->t_len; - if (accessor->write_pointer + size > accessor->write_end) + if (accessor->write_pointer == NULL || + accessor->write_pointer + size > accessor->write_end) { if (accessor->write_chunk == NULL) { -- 2.52.0