tree 4cd879277e1080938d7dfcfa9e31dd027aa6c481
parent 14d68da02a2966f57b46c9da8b4ec8c1a3a57fc0
author Zentaro Kavanagh <zentaro@chromium.org> 1524751975 -0700
committer chrome-bot <chrome-bot@chromium.org> 1525418031 -0700

installer: Prevent kernel key rollforward during recovery.

- Sets the kernel_max_rollforward value to 0 to prevent the kernel
  key versions from rolling forward before the device has a chance
  to see policy.
- The update_engine will set the value based on rollback policy
  and the key version numbers of the earliest image we allow
  rollback to. By default 4 in the past.
- Consumer devices and devices with rollback disabled will have this
  value set to logical infinity, which always rolls forward the min
  versions. This was the existing behavior.

BUG=chromium:814090
TEST=none

Change-Id: I74319eb5b6a4fb74fcfa3006b0a36b36959d4d73
Reviewed-on: https://chromium-review.googlesource.com/1030260
Commit-Ready: Marton Hunyady <hunyadym@chromium.org>
Tested-by: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Marton Hunyady <hunyadym@chromium.org>