commit ac9099a96e1d0830cf9df36721deef5f8ee2561a
author Christos Froussios <cfroussios@chromium.org> Tue Apr 26 10:15:13 2022
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Apr 26 10:15:13 2022
tree 77dd3d2e9d7e8563cdba9872fb72ee7e33be4261
parent 9e57d06f51291b3938f1985a73456880e8660d72

Revert "Map shared memory mappings backing ArrayBuffers into the V8 Sandbox"

This reverts commit e6b8260468792092e1914363c6e0556e616d76c9.

Reason for revert: broke compilation on Win x64 Builder (dbg)
https://ci.chromium.org/ui/p/chromium/builders/ci/Win%20x64%20Builder%20(dbg)/136614/overview

Original change's description:
> Map shared memory mappings backing ArrayBuffers into the V8 Sandbox
>
> When the V8 sandbox is enabled, ArrayBuffers are referenced through
> offsets rather than raw pointers to prevent their abuse by an exploit.
> This requires that all ArrayBuffer backing stores be mapped into the
> sandbox address space. As some ArrayBuffers, for example those created by
> MojoJS, are backed by shared memory, additional logic is required to map
> shared memory into the V8 sandbox. This CL achieves this as follows:
>
> 1. A new SharedMemoryMapper interface is introduced which is responsible
>    for mapping and unmapping shared memory regions. With that, it is
>    then possible to customize the mapping/unmapping logic by passing a
>    custom SharedMemoryMapper to *SharedMemoryRegion::Map.
> 2. A subclass, ArrayBufferSharedMemoryMapper is provided which maps the
>    shared memory regions into the V8 sandbox when that is enabled.
> 3. A new ArrayBufferContents constructor is created which accepts a
>    shared memory region as arguments and takes care of mapping it using
>    the appropriate SharedMemoryMapper. This constructor is now used when
>    mapping shared memory for MojoJS.
>
> Bug: 1218005
> Change-Id: Ifce853f85397f8395746904e6a4d3fe30ffd318f
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3596033
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Reviewed-by: Daniel Cheng <dcheng@chromium.org>
> Owners-Override: Daniel Cheng <dcheng@chromium.org>
> Commit-Queue: Samuel Groß <saelo@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#996070}

Bug: 1218005
Change-Id: I634baf628db2f6c462e6d62d3c29d634cd300c44
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3607950
Auto-Submit: Christos Froussios <cfroussios@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: Christos Froussios <cfroussios@chromium.org>
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Owners-Override: Christos Froussios <cfroussios@chromium.org>
Cr-Commit-Position: refs/heads/main@{#996082}