Fix potential decrypt src pointer overflow. am: c9b5693c7f am: 425466627b am: e0db28bc6c am: 68e65826c0 am: 227bdb51d0 am: 2473318b10

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

Change-Id: I6f41371c8ece37b4691a8ee2db85af053273d474