onnxruntime

a6e96aa7 - Validate 'num_scan_inputs' attribute in Scan kernel construction (#31668)

Validate 'num_scan_inputs' attribute in Scan kernel construction (#31668) ### Description The `Scan` operator's `num_scan_inputs` attribute determines how many of the node's variadic inputs are scan inputs (the remainder are loop state variables). In `scan::detail::Info::Info` (shared by the CPU `Scan-8`/`Scan-9` kernels, and reused as-is by the CUDA `Scan` kernel), this attribute was used in two unguarded subtractions: ```cpp num_loop_state_variables = num_variadic_inputs - num_scan_inputs; ... num_scan_outputs = num_outputs - num_loop_state_variables; ``` If `num_scan_inputs` is outside `[0, num_variadic_inputs]`, `num_loop_state_variables` becomes negative. That value is later used, unguarded, as a loop-start index into the node's inputs during `Compute()`, resulting in out-of-range indexing. This PR adds validation of `num_scan_inputs` (and the derived `num_loop_state_variables`) in the constructor, rejecting invalid values up front with a clear error message before any arithmetic derived from them is used for indexing. ### Testing Added regression tests for both opset 8 and opset 9+ with an out-of-range `num_scan_inputs` value: - Opset 8 hits the new kernel-construction-time check directly. - Opset 9+ is caught earlier during graph resolution's standard ONNX-level shape inference (before the kernel is even constructed), so its test asserts on the shape-inference error message instead. Both tests are guarded by `#if !defined(ORT_NO_EXCEPTIONS)` since they rely on exception-based failure reporting. Ran locally (CPU-only Debug build): - `onnxruntime_provider_test --gtest_filter='Scan*'` — all 34 tests pass, including the 2 new ones. --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 77dcaf1b-748a-4379-94a7-478f7a924d73