> When working on startup improvements, I noticed that the method handle > returned by `MemoryLayout::offsetHandle` can overflow if the client calls the > handle with a base offset that is too big. > > In other similar situations, the layout API always fails with > `ArithmeticException` (see `MemoryLayout::scale`), so we should do the same > here. > > The fix is to use a `Math::addExact(long, long)` for the outermost add > operation in the computation of the offset method handle. That outermost > computation in fact is the only one that can overflow: it is an addition > between a user-provided base offset `B` and a layout offset `L`. `L` is > guaranteed not to overflow, by construction (as `L` is derived from a layout > path). But `B` + `L` might overflow, so the new logic checks for that.
Maurizio Cimadamore has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains three commits: - Merge branch 'master' into offset_overflow - Merge branch 'master' into offset_overflow - Initial push ------------- Changes: https://git.openjdk.org/jdk/pull/20662/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20662&range=01 Stats: 23 lines in 3 files changed: 14 ins; 1 del; 8 mod Patch: https://git.openjdk.org/jdk/pull/20662.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/20662/head:pull/20662 PR: https://git.openjdk.org/jdk/pull/20662
