Use unsigned long for maxiterations, fixing undefined behavior in scan with extremely large count
#2414
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Signed-off-by: Fusl <[email protected]>
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…can with extremely large count (valkey-io#2414) This one was found by [afl++](https://github.com/AFLplusplus/AFLplusplus). Executing `scan 0 count n` with a count that is within 10% of `LONG_MAX`, `count * 10` would cause `maxiterations` to overflow. This is technically not a real problem since the way `maxiterations` is used would eventually cause it to underflow back to `LONG_MAX` again and continue counting down from there but I figured we may want to fix this regardless for expected behavior correctness? Signed-off-by: Fusl <[email protected]>
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This one was found by afl++. Executing
scan 0 count nwith a count that is within 10% ofLONG_MAX,count * 10would causemaxiterationsto overflow. This is technically not a real problem since the waymaxiterationsis used would eventually cause it to underflow back toLONG_MAXagain and continue counting down from there but I figured we may want to fix this regardless for expected behavior correctness?