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  1. JDK
  2. JDK-8272541

Incorrect overflow test in Toom-Cook branch of BigInteger multiplication

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    • Subcomponent:
    • Resolved In Build:
      b13
    • CPU:
      generic
    • OS:
      generic
    • Verification:
      Verified

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        In this code

        if (bitLength(mag, mag.length) +
           bitLength(val.mag, val.mag.length) >
           32L*MAX_MAG_LENGTH) {
           reportOverflow();
        }

        In the above, bitLength() returns 'int', hence the left operand of the '>' comparison is 'int' too, but the right operand of the '>' comparison is 'long' with value == Integer.MAX_VALUE + 1 hence this condition is always false.

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                Assignee:
                bpb Brian Burkhalter
                Reporter:
                bpb Brian Burkhalter
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                  Updated:
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