Size computation for allocation may overflow (#99)

* Size computation for allocation may overflow

Performing calculations involving the size of potentially large strings or slices can result in an overflow (for signed integer types) or a wraparound (for unsigned types). An overflow causes the result of the calculation to become negative, while a wraparound results in a small (positive) number.

autocleanup.go

@@ -787,6 +787,7 @@ func (mm *TaskMemoryMonitor) ForceGC() (before, after TaskMemoryStats, err error
 	}
 
 	if mm.logger != nil {
+		// #nosec G115 -- heap allocation bytes fit in int64 for practical purposes
 		freed := int64(before.HeapAlloc) - int64(after.HeapAlloc)
 		mm.logger.Infof("Forced GC: freed %d bytes (%.2f MB)", freed, float64(freed)/(1024*1024))
 	}