Fix potential decrypt src pointer overflow. am: c9b5693c7f am: 425466627b am: e0db28bc6c am: 68e65826c0 am: c84661b1db

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/interfaces/+/13412307

Change-Id: I44da20854d1f6d1f19384502cbb0de3d037056e2