tree a3d813d83e9d0a92f3bd0581eb08abe709b21922
parent ae91f88371030bcf3e8a1759e3e5af93fd839eaa
author Mitch Phillips <31459023+hctim@users.noreply.github.com> 1620674359 -0700
committer Copybara-Service <copybara-worker@google.com> 1621995145 -0700

[Scudo] Use GWP-ASan's aligned allocations and fixup postalloc hooks.

This patch does a few cleanup things:
 1. The non-standalone scudo has a problem where GWP-ASan allocations
 may not meet alignment requirements where Scudo was requested to have
 alignment >= 16. Use the new GWP-ASan API to fix this.
 2. The standalone variant loses some debugging information inside of
 GWP-ASan because we ask GWP-ASan to allocate an aligned size in the
 frontend. This means reports end up with 'UaF on a 16-byte allocation'
 for a 1-byte allocation with 16-byte alignment. Also use the new API to
 fix this.
 3. Add post-alloc hooks for GWP-ASan intercepted allocations, and add
 stats tracking for GWP-ASan allocations.
 4. Add a small test that checks the alignment of the frontend
 allocator, so that it can be used under GWP-ASan torture mode.
 5. Add GWP-ASan torture mode as a testing configuration to catch these
 regressions.

Depends on D94830, D95889.

Reviewed By: cryptoad

Differential Revision: https://reviews.llvm.org/D95884

GitOrigin-RevId: e78b64df98878d1da56275e0c272ed58364da3ad