GitLab

When rbp was less than the offset, the check was underflowing and
incorrectly passing. Add a check for rbp < offset to detect this
situation.

Bug: 831448
Change-Id: I4f780c1573782af3ca29b0f814e93ff2dca839f2
Reviewed-on: https://chromium-review.googlesource.com/1013213Reviewed-by: Leonard Grey <lgrey@chromium.org>
Commit-Queue: Mike Wittman <wittman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#551113}