[CI] Reject out-of-vocabulary before they reach the GPU logprob path

tests/v1/sample/test_logprobs.py

@@ -4,6 +4,7 @@
 import itertools
 import math
 from collections.abc import Generator
+from types import SimpleNamespace
 from typing import get_args
 
 import pytest
@@ -20,6 +21,7 @@
 from vllm import SamplingParams
 from vllm.config.model import LogprobsMode
 from vllm.distributed import cleanup_dist_env_and_memory
+from vllm.exceptions import VLLMValidationError
 from vllm.platforms import current_platform
 
 from ...conftest import HfRunner, VllmRunner
@@ -78,6 +80,14 @@ def hf_model(hf_runner) -> Generator[HfRunner, None, None]:
         yield hf_model
 
 
+def _model_config(vocab_size: int = 10):
+    return SimpleNamespace(
+        max_logprobs=20,
+        logits_processors=None,
+        get_vocab_size=lambda: vocab_size,
+    )
+
+
 def _repeat_logprob_config(
     test_prompts,
     logprob_prompt_logprob_list: BatchLogprobsSpecType,
@@ -397,6 +407,27 @@ def test_max_logprobs():
             runner.generate(["Hello world"], sampling_params=bad_sampling_params)
 
 
+@pytest.mark.parametrize("token_ids", [[0], [0, 9]])
+def test_logprob_token_ids_validate_vocab_bounds_valid(token_ids: list[int]):
+    SamplingParams(logprob_token_ids=token_ids).verify(
+        _model_config(),
+        speculative_config=None,
+        structured_outputs_config=None,
+        tokenizer=None,
+    )
+
+
+@pytest.mark.parametrize("token_ids", [[-1], [10], [-35, 1873042417]])
+def test_logprob_token_ids_validate_vocab_bounds_invalid(token_ids: list[int]):
+    with pytest.raises(VLLMValidationError, match="logprob_token_ids"):
+        SamplingParams(logprob_token_ids=token_ids).verify(
+            _model_config(),
+            speculative_config=None,
+            structured_outputs_config=None,
+            tokenizer=None,
+        )
+
+
 def test_none_logprobs(vllm_model, example_prompts):
     """Engine should return `logprobs` and `prompt_logprobs` as `None`
 

vllm/sampling_params.py

@@ -737,6 +737,20 @@ def _validate_logprobs(self, model_config: ModelConfig) -> None:
                     parameter="logprob_token_ids",
                     value=n,
                 )
+            vocab_size = model_config.get_vocab_size()
+            invalid_token_ids = [
+                token_id
+                for token_id in self.logprob_token_ids
+                if token_id < 0 or token_id >= vocab_size
+            ]
+            if invalid_token_ids:
+                raise VLLMValidationError(
+                    f"token_id(s) {invalid_token_ids} in logprob_token_ids "
+                    f"contain out-of-vocab token ids. Vocabulary size: "
+                    f"{vocab_size}",
+                    parameter="logprob_token_ids",
+                    value=invalid_token_ids,
+                )
             if self.logprobs is not None and self.logprobs != n:
                 raise VLLMValidationError(
                     f"When both logprobs and logprob_token_ids are set, "