Widen int multiplications to long before overflow (CodeQL java/integer-multiplication-cast-to-long)#227
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…ger-multiplication-cast-to-long) In each case the product was computed in int arithmetic and only then widened to long, so a large enough operand overflows before the conversion. Add an L suffix to the first factor so the multiplication is performed in long. - JournalManagerBench.runTest: prealloc*1024*1024 (passed to preallocateFile(long)) and extension*1024*1024 (assigned to a long) convert an MByte argument to a byte count; use 1024L so the byte count is exact for any int MByte value. - SimpleTransaction: _committedTransactionCount * 1000 is evaluated as int before the division by the long "time"; the committed count can exceed ~2.1M in a long-running run, overflowing the rate calculation. Use 1000L. - AdminUI.resetRefreshTimer: _refreshInterval (int seconds) * 1000 is passed as the long period of Timer.schedule; use 1000L. Behaviour is unchanged for in-range inputs; only the silent int overflow at large inputs is removed. These are benchmark/example/admin-UI classes, not core data paths.
maximthomas
approved these changes
Jul 8, 2026
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Summary
Resolves 4
java/integer-multiplication-cast-to-longCodeQL alerts. In each spot anint * intproduct is computed in 32-bit arithmetic and only afterwards widened tolong(by assignment, alongparameter, or along-context division), so a largeoperand overflows before the widening. Forcing the multiplication into
longwithan
Lsuffix fixes it.Fixes
persistit/coreJournalManagerBenchprealloc * 1024 * 1024→1024L(product passed topreallocateFile(long)) andextension * 1024 * 1024→1024L(assigned to along) — MByte → byte-count conversions.persistit/examplesSimpleTransaction_committedTransactionCount * 1000→1000Lbefore the divide by thelongelapsed time; the committed count can exceed ~2.1M in a long run.persistit/uiAdminUI_refreshInterval * 1000→1000L, passed as thelongperiod ofTimer.schedule.Behaviour
Unchanged for in-range inputs — the products are identical; only the silent 32-bit
overflow at large inputs is removed. All three are benchmark / example / admin-UI
classes, not core data paths.
Testing
mvn -o -pl persistit/core,persistit/ui -am compile— BUILD SUCCESS.SimpleTransactionis an Ant example (no Maven module); the one-character change iscompile-trivial.