RFR: 8353468: [ubsan] arguments.cpp:2422:23: runtime error: 2.14748e+11 is outside the range of representable values of type 'int'

[Stefan Karlsson]

On Wed, 20 Aug 2025 12:12:01 GMT, Afshin Zafari <azafari at openjdk.org> wrote:

> In converting values of `-XMinf` and `-XMaxf` options to `int`, overflow was not checked. 
> The values are checked against INT_MAX and clamped.
> 
> Tests: tiers 1-5.

The failing TestHeapFreeRatio.java test tests with an extreme positive value (2147483647), but it doesn't test with an extreme negative value:


  public static void main(String args[]) throws Exception {
    testMinMaxFreeRatio( "0.1", "0.5", Validation.VALID);
    testMinMaxFreeRatio(  ".1",  ".5", Validation.VALID);
    testMinMaxFreeRatio( "0.5", "0.5", Validation.VALID);

    testMinMaxFreeRatio("=0.1", "0.5", Validation.MIN_INVALID);
    testMinMaxFreeRatio("0.1f", "0.5", Validation.MIN_INVALID);
    testMinMaxFreeRatio(
                     "INVALID", "0.5", Validation.MIN_INVALID);

    testMinMaxFreeRatio( "0.1", "0.5f", Validation.MAX_INVALID);
    testMinMaxFreeRatio( "0.1", "=0.5", Validation.MAX_INVALID);
    testMinMaxFreeRatio(
                     "0.1",  "INVALID", Validation.MAX_INVALID);

    testMinMaxFreeRatio("-0.1", "0.5", Validation.OUT_OF_RANGE);
    testMinMaxFreeRatio( "1.1", "0.5", Validation.OUT_OF_RANGE);
    testMinMaxFreeRatio(
                  "2147483647", "0.5", Validation.OUT_OF_RANGE);
    testMinMaxFreeRatio( "0.1", "-0.5", Validation.OUT_OF_RANGE);
    testMinMaxFreeRatio( "0.1",  "1.5", Validation.OUT_OF_RANGE);
    testMinMaxFreeRatio(
                   "0.1", "2147483647", Validation.OUT_OF_RANGE);

    testMinMaxFreeRatio( "0.5",  "0.1", Validation.COMBINATION_INVALID);
    testMinMaxFreeRatio(  ".5",  ".10", Validation.COMBINATION_INVALID);
    testMinMaxFreeRatio("0.12","0.100", Validation.COMBINATION_INVALID);
  }


Would ubsan hit a similar value if it did and would you have to guard against INT_MIN as well?

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PR Comment: https://git.openjdk.org/jdk/pull/26859#issuecomment-3209395616