diff --git a/Android.mk b/Android.mk index 351e81a194b660472bcf5a63a8fd2c9e19ef3756..eae860b223020a29f92fd39776bc14fd5436611f 100644 --- a/Android.mk +++ b/Android.mk @@ -83,6 +83,7 @@ sepolicy_build_files := security_classes \ initial_sids \ access_vectors \ global_macros \ + neverallow_macros \ mls_macros \ mls \ policy_capabilities \ diff --git a/domain.te b/domain.te index 5ed79c1ea8530c532cd1ae294441e36a03548141..48e2d1ac3657a1d0f581ddbacb46212251c85493 100644 --- a/domain.te +++ b/domain.te @@ -291,8 +291,8 @@ neverallow { } { fs_type -rootfs }:file execute; # Only the init property service should write to /data/property. -neverallow { domain -init } property_data_file:dir { create setattr relabelfrom rename write add_name remove_name rmdir }; -neverallow { domain -init } property_data_file:file { create setattr relabelfrom write append unlink link rename }; +neverallow { domain -init } property_data_file:dir no_w_dir_perms; +neverallow { domain -init } property_data_file:file no_w_file_perms; # Only recovery should be doing writes to /system neverallow { domain -recovery } { system_file exec_type }:dir_file_class_set diff --git a/neverallow_macros b/neverallow_macros new file mode 100644 index 0000000000000000000000000000000000000000..3593dd1bbce687e4d3039fb2d14cb887e4b3273d --- /dev/null +++ b/neverallow_macros @@ -0,0 +1,5 @@ +# +# Common neverallow permissions +define(`no_w_file_perms', `{ append create link unlink relabelfrom rename setattr write }') +define(`no_x_file_perms', `{ execute execute_no_trans }') +define(`no_w_dir_perms', `{ add_name create link relabelfrom remove_name rename reparent rmdir setattr write }') diff --git a/recovery.te b/recovery.te index 204c096a372d5ed71ba09634c4caf6c506388ab4..61c42b1380c118097562388eac9fca84539e786e 100644 --- a/recovery.te +++ b/recovery.te @@ -98,3 +98,20 @@ recovery_only(` # set scheduling parameters for a kernel domain task. allow recovery kernel:process setsched; ') + +### +### neverallow rules +### + +# Recovery should never touch /data. +# +# In particular, if /data is encrypted, it is not accessible +# to recovery anyway. +# +# For now, we only enforce write/execute restrictions, as domain.te +# contains a number of read-only rules that apply to all +# domains, including recovery. +# +# TODO: tighten this up further. +neverallow recovery data_file_type:file { no_w_file_perms no_x_file_perms }; +neverallow recovery data_file_type:dir no_w_dir_perms;