init can call setns
init now creates two mount namespaces one for pre-apexd processes and
the other for post-apexd processes. This is to mount different files to
the same mount point at /bionic. For pre-apexd processes, the bootstrap
Bionic is mounted. For post-apexd processes, the default Bionic (from
the runtime APEX) is mounted.
Using unshare and setns, init first starts with the mount namespace for
the pre-apexd and then switches to the other mount namespace when APEXes
are ready. It then occasionally switches to pre-apexd mount namespace
when it has to re-launch a pre-apexd process (e.g. the process has
crashed, etc.)
In doing so, read access to /proc/self/ns/mnt is granted to init as
well.
Bug: 120266448
Bug: 122717176
Test: m device boots
Change-Id: Idbf15cbf5cc36b9993d718d4d887cd8f23a94666
2 files changed