onnxruntime

bbf20701 - Validate input rank/size for BifurcationDetector before indexing (#31701)

Validate input rank/size for BifurcationDetector before indexing (#31701) ## Description `BifurcationDetector` unconditionally reads and/or writes element `[0]` of several tensors without first checking that they contain enough elements to do so safely: - `src_tokens`, `cur_tokens`, and `pred_tokens` are treated as flat 1-D sequences, both via `Shape().GetDims()[0]` (their reported "length") and via linear `DataRaw()` indexing. A 0-D (scalar) input has no dimensions, so `GetDims()[0]` is an out-of-range access on an empty span. - `prev_suffix_match_idx` is read at index `[0]`, and the output tensor that mirrors its shape is written at index `[0]`, regardless of how many elements it actually has. A 0-element input backs both of those accesses with an empty/null buffer. This adds explicit validation for these inputs before they are used, returning a failure `Status` (via `ORT_RETURN_IF_NOT`) rather than proceeding to index into a buffer that may not have enough elements: - `src_tokens`, `cur_tokens`, and `pred_tokens` (when present) must be 1-D tensors. - `prev_suffix_match_idx` must contain exactly one element (consistent with how it, and the output that mirrors its shape, are used elsewhere in the kernel). ## Testing Added regression tests to `onnxruntime/test/contrib_ops/bifurcation_detector_op_test.cc` covering: - A 0-element `prev_suffix_match_idx`, both with and without `pred_tokens` present. - A scalar (0-D) `src_tokens`, `cur_tokens`, and `pred_tokens`, each rejected individually. All existing tests continue to pass unchanged. `BifurcationDetector` is CPU-only; no other execution provider implements this operator. 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