diff options
| author | Tom Lane | 2026-08-10 13:38:18 +0000 |
|---|---|---|
| committer | Noah Misch | 2026-08-10 13:38:18 +0000 |
| commit | 83d0a083f178f22c60814b93d17ecacdcce76eac (patch) | |
| tree | 3546d35c6da57e67ecd608bac02e16639f84b74a | |
| parent | eb9e5529745c129c25deb04098612898998fb123 (diff) | |
Return nulls honestly in aggregate "combine" functions.
numeric_combine() and several other state-combining functions for
aggregates cheated for the case of both inputs being NULL: they
returned a null pointer without bothering to mark it as a SQL NULL.
This was harmless in the expected usage where the result would be
passed to the same combine function or a related aggregate final
function. But it's bad news from a security standpoint, because
now that value can be passed to an internal-accepting function
even if said function is strict. While a previous patch prevented
such queries from being issued, it seems like good defense-in-depth
to expend the few additional lines of code needed to do this properly.
Comparable functions such as array_agg_combine() already do so.
Reported-by: Amy Burnett (OpenAI Codex Security)
Author: Tom Lane <tgl@sss.pgh.pa.us>
Backpatch-through: 14
Security: CVE-2026-14680
| -rw-r--r-- | src/backend/utils/adt/numeric.c | 32 | ||||
| -rw-r--r-- | src/backend/utils/adt/timestamp.c | 8 |
2 files changed, 40 insertions, 0 deletions
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c index d3d33aae935..14e8895ec70 100644 --- a/src/backend/utils/adt/numeric.c +++ b/src/backend/utils/adt/numeric.c @@ -5073,7 +5073,15 @@ numeric_combine(PG_FUNCTION_ARGS) state2 = PG_ARGISNULL(1) ? NULL : (NumericAggState *) PG_GETARG_POINTER(1); if (state2 == NULL) + { + /* + * NULL state2 is easy, just return state1, which we know is already + * in the agg_context + */ + if (state1 == NULL) + PG_RETURN_NULL(); PG_RETURN_POINTER(state1); + } /* manually copy all fields from state2 to state1 */ if (state1 == NULL) @@ -5165,7 +5173,15 @@ numeric_avg_combine(PG_FUNCTION_ARGS) state2 = PG_ARGISNULL(1) ? NULL : (NumericAggState *) PG_GETARG_POINTER(1); if (state2 == NULL) + { + /* + * NULL state2 is easy, just return state1, which we know is already + * in the agg_context + */ + if (state1 == NULL) + PG_RETURN_NULL(); PG_RETURN_POINTER(state1); + } /* manually copy all fields from state2 to state1 */ if (state1 == NULL) @@ -5649,7 +5665,15 @@ numeric_poly_combine(PG_FUNCTION_ARGS) state2 = PG_ARGISNULL(1) ? NULL : (PolyNumAggState *) PG_GETARG_POINTER(1); if (state2 == NULL) + { + /* + * NULL state2 is easy, just return state1, which we know is already + * in the agg_context + */ + if (state1 == NULL) + PG_RETURN_NULL(); PG_RETURN_POINTER(state1); + } /* manually copy all fields from state2 to state1 */ if (state1 == NULL) @@ -5852,7 +5876,15 @@ int8_avg_combine(PG_FUNCTION_ARGS) state2 = PG_ARGISNULL(1) ? NULL : (PolyNumAggState *) PG_GETARG_POINTER(1); if (state2 == NULL) + { + /* + * NULL state2 is easy, just return state1, which we know is already + * in the agg_context + */ + if (state1 == NULL) + PG_RETURN_NULL(); PG_RETURN_POINTER(state1); + } /* manually copy all fields from state2 to state1 */ if (state1 == NULL) diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c index afd5d7f7502..b57739b7e83 100644 --- a/src/backend/utils/adt/timestamp.c +++ b/src/backend/utils/adt/timestamp.c @@ -4035,7 +4035,15 @@ interval_avg_combine(PG_FUNCTION_ARGS) state2 = PG_ARGISNULL(1) ? NULL : (IntervalAggState *) PG_GETARG_POINTER(1); if (state2 == NULL) + { + /* + * NULL state2 is easy, just return state1, which we know is already + * in the agg_context + */ + if (state1 == NULL) + PG_RETURN_NULL(); PG_RETURN_POINTER(state1); + } if (state1 == NULL) { |