Updated policy for external storage.
An upcoming platform release is redesigning how external storage
works. At a high level, vold is taking on a more active role in
managing devices that dynamically appear.
This change also creates further restricted domains for tools doing
low-level access of external storage devices, including sgdisk
and blkid. It also extends sdcardd to be launchable by vold, since
launching by init will eventually go away.
For compatibility, rules required to keep AOSP builds working are
marked with "TODO" to eventually remove.
Slightly relax system_server external storage rules to allow calls
like statfs(). Still neverallow open file descriptors, since they
can cause kernel to kill us.
Here are the relevant violations that this CL is designed to allow:
avc: denied { search } for name="user" dev="tmpfs" ino=7441 scontext=u:r:zygote:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { getattr } for path="/mnt/user/0" dev="tmpfs" ino=6659 scontext=u:r:zygote:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { write } for name="user" dev="tmpfs" ino=6658 scontext=u:r:zygote:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { add_name } for name="10" scontext=u:r:zygote:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { create } for name="10" scontext=u:r:zygote:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { setattr } for name="10" dev="tmpfs" ino=11348 scontext=u:r:zygote:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { search } for name="/" dev="tmpfs" ino=3131 scontext=u:r:zygote:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { getattr } for path="/storage" dev="tmpfs" ino=6661 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { getattr } for path="/storage/self" dev="tmpfs" ino=6659 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { getattr } for path="/storage" dev="tmpfs" ino=6661 scontext=u:r:untrusted_app:s0:c522,c768 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { getattr } for path="/storage/self" dev="tmpfs" ino=11348 scontext=u:r:untrusted_app:s0:c522,c768 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { getattr } for path="/storage" dev="tmpfs" ino=6661 scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { read } for name="/" dev="tmpfs" ino=6661 scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { open } for name="/" dev="tmpfs" ino=6661 scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { search } for name="/" dev="tmpfs" ino=6661 scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { write } for name="data" dev="tmpfs" ino=11979 scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { add_name } for name="com.google.android.music" scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { create } for name="com.google.android.music" scontext=u:r:vold:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { use } for path="socket:[8297]" dev="sockfs" ino=8297 scontext=u:r:sdcardd:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { read write } for path="socket:[8297]" dev="sockfs" ino=8297 scontext=u:r:sdcardd:s0 tcontext=u:r:vold:s0 tclass=netlink_kobject_uevent_socket
avc: denied { read } for path="pipe:[8298]" dev="pipefs" ino=8298 scontext=u:r:sdcardd:s0 tcontext=u:r:vold:s0 tclass=fifo_file
avc: denied { write } for path="pipe:[8298]" dev="pipefs" ino=8298 scontext=u:r:sdcardd:s0 tcontext=u:r:vold:s0 tclass=fifo_file
avc: denied { mounton } for path="/storage/emulated" dev="tmpfs" ino=8913 scontext=u:r:sdcardd:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { getattr } for path="/storage" dev="tmpfs" ino=7444 scontext=u:r:system_server:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { getattr } for path="/storage/self/primary" dev="tmpfs" ino=7447 scontext=u:r:system_server:s0 tcontext=u:object_r:storage_file:s0 tclass=lnk_file
avc: denied { read } for name="primary" dev="tmpfs" ino=7447 scontext=u:r:system_server:s0 tcontext=u:object_r:storage_file:s0 tclass=lnk_file
avc: denied { getattr } for path="/mnt/user" dev="tmpfs" ino=7441 scontext=u:r:system_server:s0 tcontext=u:object_r:mnt_user_file:s0 tclass=dir
avc: denied { read } for name="disk:179,128" dev="tmpfs" ino=3224 scontext=u:r:sgdisk:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { open } for path="/dev/block/vold/disk:179,128" dev="tmpfs" ino=3224 scontext=u:r:sgdisk:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { getattr } for path="/dev/block/vold/disk:179,128" dev="tmpfs" ino=3224 scontext=u:r:sgdisk:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { read } for name="/" dev="fuse" ino=0 scontext=u:r:vold:s0 tcontext=u:object_r:fuse:s0 tclass=dir
avc: denied { open } for path="/storage/public:81F3-13EC" dev="fuse" ino=0 scontext=u:r:vold:s0 tcontext=u:object_r:fuse:s0 tclass=dir
avc: denied { write } for name="data" dev="fuse" ino=2 scontext=u:r:vold:s0 tcontext=u:object_r:fuse:s0 tclass=dir
avc: denied { add_name } for name="com.google.android.googlequicksearchbox" scontext=u:r:vold:s0 tcontext=u:object_r:fuse:s0 tclass=dir
avc: denied { create } for name="com.google.android.googlequicksearchbox" scontext=u:r:vold:s0 tcontext=u:object_r:fuse:s0 tclass=dir
avc: denied { getattr } for path="/dev/block/vold/public:179,129" dev="tmpfs" ino=16953 scontext=u:r:blkid:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { read } for name="public:179,129" dev="tmpfs" ino=16953 scontext=u:r:blkid:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { open } for path="/dev/block/vold/public:179,129" dev="tmpfs" ino=16953 scontext=u:r:blkid:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { ioctl } for path="/dev/block/vold/public:179,129" dev="tmpfs" ino=16953 scontext=u:r:blkid:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file
avc: denied { use } for path="pipe:[3264]" dev="pipefs" ino=3264 scontext=u:r:sgdisk:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { use } for path="pipe:[3264]" dev="pipefs" ino=3264 scontext=u:r:sgdisk:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { search } for name="block" dev="tmpfs" ino=2494 scontext=u:r:sgdisk:s0 tcontext=u:object_r:block_device:s0 tclass=dir
avc: denied { use } for path="pipe:[4200]" dev="pipefs" ino=4200 scontext=u:r:sdcardd:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { use } for path="pipe:[4200]" dev="pipefs" ino=4200 scontext=u:r:sdcardd:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { search } for name="/" dev="tmpfs" ino=3131 scontext=u:r:sdcardd:s0 tcontext=u:object_r:storage_file:s0 tclass=dir
avc: denied { search } for name="media_rw" dev="tmpfs" ino=3127 scontext=u:r:sdcardd:s0 tcontext=u:object_r:mnt_media_rw_file:s0 tclass=dir
avc: denied { getattr } for path="pipe:[3648]" dev="pipefs" ino=3648 scontext=u:r:blkid:s0 tcontext=u:r:vold:s0 tclass=fifo_file
avc: denied { use } for path="/dev/pts/12" dev="devpts" ino=15 scontext=u:r:fsck:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { use } for path="/dev/pts/12" dev="devpts" ino=15 scontext=u:r:fsck:s0 tcontext=u:r:vold:s0 tclass=fd
avc: denied { use } for path="pipe:[4182]" dev="pipefs" ino=4182 scontext=u:r:fsck:s0 tcontext=u:r:vold:s0 tclass=fd
Change-Id: Idf3b8561baecf7faa603fac5ababdcc5708288e1
diff --git a/sgdisk.te b/sgdisk.te
new file mode 100644
index 0000000..66656b6
--- /dev/null
+++ b/sgdisk.te
@@ -0,0 +1,16 @@
+# sgdisk called from vold
+type sgdisk, domain;
+type sgdisk_exec, exec_type, file_type;
+
+# Allowed to read/write low-level partition tables
+allow sgdisk block_device:dir search;
+allow sgdisk vold_device:blk_file rw_file_perms;
+
+# Allow stdin/out back to vold
+allow sgdisk vold:fd use;
+allow sgdisk vold:fifo_file { read write getattr };
+
+# Only allow entry from vold
+neverallow { domain -vold } sgdisk:process transition;
+neverallow domain sgdisk:process dyntransition;
+neverallow sgdisk { file_type fs_type -sgdisk_exec }:file entrypoint;