From 8e81995de30c5a1834d7dae56a6396067d491975 Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Mon, 11 May 2026 05:13:51 -0700 Subject: [PATCH] Fix integer overflow in array_agg(), when the array grows too large If you accumulate many arrays full of NULLs, you could overflow 'nitems', before reaching the MaxAllocSize limit on the allocations. Add an explicit check that the number of items doesn't grow too large. With more than MaxArraySize items, getting the final result with makeArrayResultArr() would fail anyway, so better to error out early. Reported-by: Xint Code Author: Heikki Linnakangas Reviewed-by: Tom Lane Backpatch-through: 14 Security: CVE-2026-6473 --- src/backend/utils/adt/arrayfuncs.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c index 6eb9f293318..fee1ebd160a 100644 --- a/src/backend/utils/adt/arrayfuncs.c +++ b/src/backend/utils/adt/arrayfuncs.c @@ -5542,6 +5542,7 @@ accumArrayResultArr(ArrayBuildStateArr *astate, ndatabytes; char *data; int i; + int newnitems; /* * We disallow accumulating null subarrays. Another plausible definition @@ -5571,6 +5572,14 @@ accumArrayResultArr(ArrayBuildStateArr *astate, nitems = ArrayGetNItems(ndims, dims); ndatabytes = ARR_SIZE(arg) - ARR_DATA_OFFSET(arg); + /* Check that the array doesn't grow too large */ + newnitems = astate->nitems + nitems; + if (newnitems > MaxArraySize) + ereport(ERROR, + (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), + errmsg("array size exceeds the maximum allowed (%zu)", + MaxArraySize))); + if (astate->ndims == 0) { /* First input; check/save the dimensionality info */ @@ -5636,8 +5645,6 @@ accumArrayResultArr(ArrayBuildStateArr *astate, /* Deal with null bitmap if needed */ if (astate->nullbitmap || ARR_HASNULL(arg)) { - int newnitems = astate->nitems + nitems; - if (astate->nullbitmap == NULL) { /* @@ -5661,7 +5668,7 @@ accumArrayResultArr(ArrayBuildStateArr *astate, nitems); } - astate->nitems += nitems; + astate->nitems = newnitems; astate->dims[0] += 1; MemoryContextSwitchTo(oldcontext);