platform_system_sepolicy/public/global_macros
Nick Kralevich c4ab8edf74 global_macros: trim back various watch* permissions
Commit dddbaaf1e8 ("update sepolicy
for fs notification hooks") updated global macros, and added
watch, watch_mount, watch_sb, watch_with_perm, and watch_reads
to r_file_perms and r_dir_perms.

In retrospect, the commit was overly permissive and some of the
permissions shouldn't be granted by default. In particular:

1) watch_with_perm: This is only used with fanotify and requires
CAP_SYS_ADMIN. fanotify has limited use cases, including virus scanning
and hierarchical storage management. Granting this by default makes it
harder to audit and understand this powerful capability. In particular,
anti-virus file like monitoring is something which inherently conflicts
with Android app privacy guarantees and would need to be carefully
reviewed.

2) watch_mount & watch_sb: Setting a watch on a mount (FAN_MARK_MOUNT)
or superblock (FAN_MARK_FILESYSTEM) should be extremely unusual.
Granting this by default makes it harder to audit and understand.

Both "watch" and "watch_reads" are retained for now.

References:
* https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=ac5656d8a4cdd93cd2c74355ed12e5617817e0e7
* dddbaaf1e8

Test: compiles
Change-Id: Ib74e7119853eb991e0e9828645c7f9e076b919c4
2019-08-28 12:36:58 -07:00

51 lines
3.6 KiB
Text

#####################################
# Common groupings of object classes.
#
define(`capability_class_set', `{ capability capability2 cap_userns cap2_userns }')
define(`global_capability_class_set', `{ capability cap_userns }')
define(`global_capability2_class_set', `{ capability2 cap2_userns }')
define(`devfile_class_set', `{ chr_file blk_file }')
define(`notdevfile_class_set', `{ file lnk_file sock_file fifo_file }')
define(`file_class_set', `{ devfile_class_set notdevfile_class_set }')
define(`dir_file_class_set', `{ dir file_class_set }')
define(`socket_class_set', `{ socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket appletalk_socket netlink_route_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_dnrt_socket netlink_kobject_uevent_socket tun_socket netlink_iscsi_socket netlink_fib_lookup_socket netlink_connector_socket netlink_netfilter_socket netlink_generic_socket netlink_scsitransport_socket netlink_rdma_socket netlink_crypto_socket sctp_socket icmp_socket ax25_socket ipx_socket netrom_socket atmpvc_socket x25_socket rose_socket decnet_socket atmsvc_socket rds_socket irda_socket pppox_socket llc_socket can_socket tipc_socket bluetooth_socket iucv_socket rxrpc_socket isdn_socket phonet_socket ieee802154_socket caif_socket alg_socket nfc_socket vsock_socket kcm_socket qipcrtr_socket smc_socket xdp_socket }')
define(`dgram_socket_class_set', `{ udp_socket unix_dgram_socket }')
define(`stream_socket_class_set', `{ tcp_socket unix_stream_socket sctp_socket }')
define(`unpriv_socket_class_set', `{ tcp_socket udp_socket unix_stream_socket unix_dgram_socket sctp_socket }')
define(`network_socket_class_set', `{ icmp_socket rawip_socket tcp_socket udp_socket }')
define(`ipc_class_set', `{ sem msgq shm ipc }')
#####################################
# Common groupings of permissions.
#
define(`x_file_perms', `{ getattr execute execute_no_trans map }')
define(`r_file_perms', `{ getattr open read ioctl lock map watch watch_reads }')
define(`w_file_perms', `{ open append write lock map }')
define(`rx_file_perms', `{ r_file_perms x_file_perms }')
define(`ra_file_perms', `{ r_file_perms append }')
define(`rw_file_perms', `{ r_file_perms w_file_perms }')
define(`rwx_file_perms', `{ rw_file_perms x_file_perms }')
define(`create_file_perms', `{ create rename setattr unlink rw_file_perms }')
define(`r_dir_perms', `{ open getattr read search ioctl lock watch watch_reads }')
define(`w_dir_perms', `{ open search write add_name remove_name lock }')
define(`ra_dir_perms', `{ r_dir_perms add_name write }')
define(`rw_dir_perms', `{ r_dir_perms w_dir_perms }')
define(`create_dir_perms', `{ create reparent rename rmdir setattr rw_dir_perms }')
define(`r_ipc_perms', `{ getattr read associate unix_read }')
define(`w_ipc_perms', `{ write unix_write }')
define(`rw_ipc_perms', `{ r_ipc_perms w_ipc_perms }')
define(`create_ipc_perms', `{ create setattr destroy rw_ipc_perms }')
#####################################
# Common socket permission sets.
define(`rw_socket_perms', `{ ioctl read getattr write setattr lock append bind connect getopt setopt shutdown map }')
define(`rw_socket_perms_no_ioctl', `{ read getattr write setattr lock append bind connect getopt setopt shutdown map }')
define(`create_socket_perms', `{ create rw_socket_perms }')
define(`create_socket_perms_no_ioctl', `{ create rw_socket_perms_no_ioctl }')
define(`rw_stream_socket_perms', `{ rw_socket_perms listen accept }')
define(`create_stream_socket_perms', `{ create rw_stream_socket_perms }')