Set protections on MAP_ALIGNED platforms too for WTF::OSAllocator::tryReserveUncommittedAligned

• Component: Web Template Framework
• Status: RESOLVED FIXED

[Leonardo Taccari]

Since 247105@main when tryReserveUncommittedAligned() on Unix-like platforms that supports MAP_ALIGNED (except macOS and Linux) pages are initially mmap-ed via PROT_NONE but then the protections are never readjusted.

At least in NetBSD running jsc, e.g. via `jsc -e 0', it ends up in a SIGSEGV.

[Leonardo Taccari]

Created attachment 460075 [details]
REGRESSION(247105@main): Set protections on MAP_ALIGNED platforms too

Since the introduction of tryReserveUncommittedAligned() on platforms
that have MAP_ALIGNED via 247105@main, reserved pages via that
function never had the protections adjusted and will likely ends
up in SIGSEGV.

[Leonardo Taccari]

After this patch and https://bugs.webkit.org/show_bug.cgi?id=241386 is applied jsc should build and runs on NetBSD too without any further patches.

[Leonardo Taccari]

Comment on attachment 460075 [details]
REGRESSION(247105@main): Set protections on MAP_ALIGNED platforms too

Mark it as ready for review.

[Yusuke Suzuki]

@Leonardo Also I recommend joining WebKit slack from https://webkit.org/getting-started/
And joining #jsc / #reviews channel. There are JSC reviewers you can ask for reviews :)

[Leonardo Taccari]

Great suggestion! I'm there too now! :)

Thank you very much Yusuke!

[Yusuke Suzuki]

Comment on attachment 460075 [details]
REGRESSION(247105@main): Set protections on MAP_ALIGNED platforms too

r=me

[EWS]

Committed r295382 (251390@main): <https://commits.webkit.org/251390@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 460075 [details].

[Radar WebKit Bug Importer]

<rdar://problem/94641219>