From c283e542a3f422420cfdb332414543b62fc4e4a5 Mon Sep 17 00:00:00 2001
From: Laura Pak <lpak@google.com>
Date: Tue, 27 Jul 2021 10:55:35 -0700
Subject: [PATCH] Disallow negative ngram_widths values in
 tf.raw_ops.StringNGrams

PiperOrigin-RevId: 387148179
Change-Id: I641395a09a208be72ef9b3ceb128cf8a83a0775b
---
 tensorflow/core/kernels/string_ngrams_op.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tensorflow/core/kernels/string_ngrams_op.cc b/tensorflow/core/kernels/string_ngrams_op.cc
index 7008a1d766af2..97af9abc4454a 100644
--- a/tensorflow/core/kernels/string_ngrams_op.cc
+++ b/tensorflow/core/kernels/string_ngrams_op.cc
@@ -53,6 +53,12 @@ class StringNGramsOp : public tensorflow::OpKernel {
   }
 
   void Compute(tensorflow::OpKernelContext* context) override {
+    for (int ngram_width : ngram_widths_) {
+      OP_REQUIRES(
+          context, ngram_width > 0,
+          errors::InvalidArgument("ngram_widths must contain positive values"));
+    }
+
     const tensorflow::Tensor* data;
     OP_REQUIRES_OK(context, context->input("data", &data));
     const auto& input_data = data->flat<tstring>().data();