To determine if it is safe to run fsck on a filesystem, e2fsck
must first determine if the filesystem is mounted. To do that,
e2fsck scans through /proc/mounts and collects all the mounted
block devices. With that information, it runs stat() on each block
device, comparing the major and minor numbers to the filesystem
passed in on the command line. If there is a match, then the filesystem
is currently mounted and running fsck is dangerous.
Allow stat access to all block devices so that fsck can compare
major/minor values.
Addresses the following denials:
avc: denied { getattr } for comm="e2fsck" path="/dev/block/sde5"
dev="tmpfs" ino=15649 scontext=u:r:fsck:s0
tcontext=u:object_r:metadata_block_device:s0 tclass=blk_file
permissive=0
avc: denied { getattr } for comm="e2fsck" path="/dev/block/sda25"
dev="tmpfs" ino=15528 scontext=u:r:fsck:s0
tcontext=u:object_r:modem_block_device:s0 tclass=blk_file permissive=0
avc: denied { getattr } for comm="e2fsck" path="/dev/block/sda31"
dev="tmpfs" ino=15552 scontext=u:r:fsck:s0
tcontext=u:object_r:system_block_device:s0 tclass=blk_file permissive=0
avc: denied { getattr } for comm="e2fsck" path="/dev/block/sdd3"
dev="tmpfs" ino=15600 scontext=u:r:fsck:s0
tcontext=u:object_r:block_device:s0 tclass=blk_file permissive=0
Bug: 35324014
Bug: 33781554
Test: device boots and no SELinux denials.
Change-Id: I5af4a334ec41952887914eec4eee5c60cc441a66
Divide policy into public and private components. This is the first
step in splitting the policy creation for platform and non-platform
policies. The policy in the public directory will be exported for use
in non-platform policy creation. Backwards compatibility with it will
be achieved by converting the exported policy into attribute-based
policy when included as part of the non-platform policy and a mapping
file will be maintained to be included with the platform policy that
maps exported attributes of previous versions to the current platform
version.
Eventually we would like to create a clear interface between the
platform and non-platform device components so that the exported policy,
and the need for attributes is minimal. For now, almost all types and
avrules are left in public.
Test: Tested by building policy and running on device.
Change-Id: Idef796c9ec169259787c3f9d8f423edf4ce27f8c
