platform_system_sepolicy/public/fsck.te
Tri Vo 62f2842c80 Explicitly label filesystem files in /proc
proc files needed by fwk that were labeled:
/proc/filesystems -> proc_filesystems
/proc/mounts -> proc_mounts
/proc/swaps -> proc_mounts

Removed access to proc label from these domains:
e2fs, fsck, fsck_untrusted, sdcardd

e2fs: added access to proc_filesystems, proc_mounts, proc_swaps
fsck: added access to proc_mounts, proc_swaps
fsck_untrusted: added access to proc_mounts
sdcardd: added access to proc_filesystems
vold: added access to proc_filesystems, proc_mounts

Bug: 66199084
Test: device boots without selinux denials to new labels or proc label.
Change-Id: If0f19e22074419dab0b3a0c6f3a300ea8cb94523
2017-09-20 15:13:08 -07:00

58 lines
1.8 KiB
Text

# Any fsck program run by init
type fsck, domain;
type fsck_exec, exec_type, file_type;
# /dev/__null__ created by init prior to policy load,
# open fd inherited by fsck.
allow fsck tmpfs:chr_file { read write ioctl };
# Inherit and use pty created by android_fork_execvp_ext().
allow fsck devpts:chr_file { read write ioctl getattr };
# Allow stdin/out back to vold
allow fsck vold:fd use;
allow fsck vold:fifo_file { read write getattr };
# Run fsck on certain block devices
allow fsck block_device:dir search;
allow fsck userdata_block_device:blk_file rw_file_perms;
allow fsck cache_block_device:blk_file rw_file_perms;
allow fsck dm_device:blk_file rw_file_perms;
# 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.
allow fsck dev_type:blk_file getattr;
allow fsck {
proc_mounts
proc_swaps
}:file r_file_perms;
allow fsck rootfs:dir r_dir_perms;
###
### neverallow rules
###
# fsck should never be run on these block devices
neverallow fsck {
boot_block_device
frp_block_device
metadata_block_device
recovery_block_device
root_block_device
swap_block_device
system_block_device
vold_device
}:blk_file no_rw_file_perms;
# Only allow entry from init or vold via fsck binaries
neverallow { domain -init -vold } fsck:process transition;
neverallow * fsck:process dyntransition;
neverallow fsck { file_type fs_type -fsck_exec }:file entrypoint;