tree 0248fe8eeb3810c803df7c6f06d1154b33eecc5d
parent 37896101eae3d88a142e7d659140ff20dc45a807
author Janis Danisevskis <jdanis@google.com> 1556664239 -0700
committer Janis Danisevskis <jdanis@google.com> 1556925546 -0700

Fix grants get lost on key upgrade

The upgrade routine used to call KeyStore->del which purges the given
key blob from the keystore including all existing grants.
With this patch, upgrade only calls Keymaster::delete on the keyblobs
without purging it from the keystore. Also it only calls
Keymaster::delete once the upgrade key was successfully written to disk.

This patch also calls fsync on the directory containing keyblobs to
narrow the window in which keyblob may be lost due to power loss.

Bug: 110450771
Test: Upgrade path tested by manually creating a key, bumping the
      patchlevel, using the key subsequently and inspecting the logs.
Change-Id: I89241b5d4033b270733ff61838ab9244fce28c60