| # lmkd low memory killer daemon |
| type lmkd, domain, mlstrustedsubject; |
| type lmkd_exec, system_file_type, exec_type, file_type; |
| |
| allow lmkd self:global_capability_class_set { dac_override dac_read_search sys_resource kill }; |
| |
| # lmkd locks itself in memory, to prevent it from being |
| # swapped out and unable to kill other memory hogs. |
| # system/core commit b28ff9131363f7b4a698990da5748b2a88c3ed35 |
| # b/16236289 |
| allow lmkd self:global_capability_class_set ipc_lock; |
| |
| ## Open and write to /proc/PID/oom_score_adj and /proc/PID/timerslack_ns |
| ## TODO: maybe scope this down? |
| r_dir_file(lmkd, domain) |
| allow lmkd domain:file write; |
| |
| ## Writes to /sys/module/lowmemorykiller/parameters/minfree |
| r_dir_file(lmkd, sysfs_lowmemorykiller) |
| allow lmkd sysfs_lowmemorykiller:file w_file_perms; |
| |
| # setsched and send kill signals to any registered process |
| allow lmkd domain:process { setsched sigkill }; |
| # TODO: delete this line b/131761776 |
| allow lmkd kernel:process { setsched }; |
| |
| # Clean up old cgroups |
| allow lmkd cgroup:dir { remove_name rmdir }; |
| |
| # Allow to read memcg stats |
| allow lmkd cgroup:file r_file_perms; |
| |
| # Set self to SCHED_FIFO |
| allow lmkd self:global_capability_class_set sys_nice; |
| |
| allow lmkd proc_zoneinfo:file r_file_perms; |
| allow lmkd proc_vmstat:file r_file_perms; |
| |
| # Set sys.lmk.* properties. |
| set_prop(lmkd, system_lmk_prop) |
| |
| # live lock watchdog process allowed to look through /proc/ |
| allow lmkd domain:dir { search open read }; |
| allow lmkd domain:file { open read }; |
| |
| # live lock watchdog process allowed to dump process trace and |
| # reboot because orderly shutdown may not be possible. |
| allow lmkd proc_sysrq:file rw_file_perms; |
| |
| # Read /proc/lowmemorykiller |
| allow lmkd proc_lowmemorykiller:file r_file_perms; |
| |
| # Read /proc/meminfo |
| allow lmkd proc_meminfo:file r_file_perms; |
| |
| # Read /proc/pressure/cpu and /proc/pressure/io |
| allow lmkd proc_pressure_cpu:file r_file_perms; |
| allow lmkd proc_pressure_io:file r_file_perms; |
| |
| # Read/Write /proc/pressure/memory |
| allow lmkd proc_pressure_mem:file rw_file_perms; |
| |
| # Allow lmkd to connect during reinit. |
| allow lmkd lmkd_socket:sock_file write; |
| |
| # Allow lmkd to write to statsd. |
| unix_socket_send(lmkd, statsdw, statsd) |
| |
| ### neverallow rules |
| |
| # never honor LD_PRELOAD |
| neverallow * lmkd:process noatsecure; |
| neverallow lmkd self:global_capability_class_set sys_ptrace; |