policy_module(kernel, 1.17.1) ######################################## # # Declarations # ## ##

## Disable kernel module loading. ##

## gen_bool(secure_mode_insmod, false) # assertion related attributes attribute can_load_kernmodule; attribute can_receive_kernel_messages; attribute can_dump_kernel; neverallow ~can_load_kernmodule self:capability sys_module; # domains with unconfined access to kernel resources attribute kern_unconfined; # regular entries in proc attribute proc_type; # attribute for domains which read proc_t attribute kernel_system_state_reader; # sysctls attribute sysctl_type; role system_r; role sysadm_r; role staff_r; role user_r; # here until order dependence is fixed: role unconfined_r; role guest_r; role xguest_r; ifdef(`enable_mls',` role secadm_r; role auditadm_r; ') # # kernel_t is the domain of kernel threads. # It is also the target type when checking permissions in the system class. # type kernel_t, can_load_kernmodule; domain_base_type(kernel_t) mls_rangetrans_source(kernel_t) mls_trusted_object(kernel_t) role system_r types kernel_t; sid kernel gen_context(system_u:system_r:kernel_t,mls_systemhigh) # # BinderFS # type binderfs_t; fs_type(binderfs_t) genfscon binder / gen_context(system_u:object_r:binderfs_t,s0) # # DebugFS # type debugfs_t; files_mountpoint(debugfs_t) fs_type(debugfs_t) dev_associate_sysfs(debugfs_t) allow debugfs_t self:filesystem associate; genfscon debugfs / gen_context(system_u:object_r:debugfs_t,s0) # # kvmFS # type kvmfs_t; fs_type(kvmfs_t) genfscon kvmfs / gen_context(system_u:object_r:kvmfs_t,s0) # # Procfs types # type proc_t, proc_type; files_mountpoint(proc_t) fs_type(proc_t) genfscon proc / gen_context(system_u:object_r:proc_t,s0) genfscon proc /sysvipc gen_context(system_u:object_r:proc_t,s0) type proc_afs_t, proc_type; fs_associate(proc_afs_t) genfscon proc /fs/openafs gen_context(system_u:object_r:proc_afs_t,s0) # kernel message interface type proc_kmsg_t, proc_type; fs_associate(proc_kmsg_t) genfscon proc /kmsg gen_context(system_u:object_r:proc_kmsg_t,mls_systemhigh) neverallow ~{ can_receive_kernel_messages kern_unconfined } proc_kmsg_t:file ~getattr; # /proc kcore: inaccessible type proc_kcore_t, proc_type; fs_associate(proc_kcore_t) neverallow ~{ can_dump_kernel kern_unconfined } proc_kcore_t:file ~getattr; genfscon proc /kcore gen_context(system_u:object_r:proc_kcore_t,mls_systemhigh) type proc_mdstat_t, proc_type; fs_associate(proc_mdstat_t) genfscon proc /mdstat gen_context(system_u:object_r:proc_mdstat_t,s0) type proc_numa_t, proc_type; fs_associate(proc_numa_t) genfscon proc /numatools gen_context(system_u:object_r:proc_numa_t,s0) mls_trusted_object(proc_numa_t) type proc_net_t, proc_type; fs_associate(proc_net_t) genfscon proc /net gen_context(system_u:object_r:proc_net_t,s0) type proc_security_t, proc_type; fs_associate(proc_security_t) genfscon proc /sys/fs/protected_hardlinks gen_context(system_u:object_r:proc_security_t,s0) genfscon proc /sys/fs/protected_symlinks gen_context(system_u:object_r:proc_security_t,s0) genfscon proc /sys/fs/suid_dumpable gen_context(system_u:object_r:proc_security_t,s0) genfscon proc /sys/kernel/dmesg_restrict gen_context(system_u:object_r:proc_security_t,s0) genfscon proc /sys/kernel/kptr_restrict gen_context(system_u:object_r:proc_security_t,s0) genfscon proc /sys/kernel/modules_disabled gen_context(system_u:object_r:proc_security_t,s0) genfscon proc /sys/kernel/randomize_va_space gen_context(system_u:object_r:proc_security_t,s0) type usermodehelper_t, proc_type, sysctl_type; typealias usermodehelper_t alias sysctl_hotplug_t; typealias usermodehelper_t alias sysctl_modprobe_t; dev_associate_sysfs(usermodehelper_t) fs_associate(usermodehelper_t) genfscon proc /sys/kernel/core_pattern gen_context(system_u:object_r:usermodehelper_t,s0) genfscon proc /sys/kernel/hotplug gen_context(system_u:object_r:usermodehelper_t,s0) genfscon proc /sys/kernel/modprobe gen_context(system_u:object_r:usermodehelper_t,s0) genfscon proc /sys/kernel/poweroff_cmd gen_context(system_u:object_r:usermodehelper_t,s0) genfscon proc /sys/kernel/usermodehelper gen_context(system_u:object_r:usermodehelper_t,s0) type proc_xen_t, proc_type; files_mountpoint(proc_xen_t) genfscon proc /xen gen_context(system_u:object_r:proc_xen_t,s0) # # Sysctl types # # /proc/sys directory, base directory of sysctls type sysctl_t, sysctl_type; files_mountpoint(sysctl_t) sid sysctl gen_context(system_u:object_r:sysctl_t,s0) genfscon proc /sys gen_context(system_u:object_r:sysctl_t,s0) # /proc/irq directory and files type sysctl_irq_t, sysctl_type; fs_associate(sysctl_irq_t) fs_associate_proc(sysctl_irq_t) genfscon proc /irq gen_context(system_u:object_r:sysctl_irq_t,s0) # /proc/net/rpc directory and files type sysctl_rpc_t, sysctl_type; fs_associate(sysctl_rpc_t) fs_associate_proc(sysctl_rpc_t) genfscon proc /net/rpc gen_context(system_u:object_r:sysctl_rpc_t,s0) # /proc/sys/crypto directory and files type sysctl_crypto_t, sysctl_type; fs_associate_proc(sysctl_crypto_t) fs_associate(sysctl_crypto_t) genfscon proc /sys/crypto gen_context(system_u:object_r:sysctl_crypto_t,s0) # /proc/sys/fs directory and files type sysctl_fs_t, sysctl_type; files_mountpoint(sysctl_fs_t) genfscon proc /sys/fs gen_context(system_u:object_r:sysctl_fs_t,s0) # /proc/sys/kernel directory and files type sysctl_kernel_t, sysctl_type; fs_associate(sysctl_kernel_t) genfscon proc /sys/kernel gen_context(system_u:object_r:sysctl_kernel_t,s0) # /sys/kernel/ns_last_pid file type sysctl_kernel_ns_last_pid_t, sysctl_type; fs_associate(sysctl_kernel_ns_last_pid_t) genfscon proc /sys/kernel/ns_last_pid gen_context(system_u:object_r:sysctl_kernel_ns_last_pid_t,s0) # /proc/sys/net directory and files type sysctl_net_t, sysctl_type; fs_associate(sysctl_net_t) genfscon proc /sys/net gen_context(system_u:object_r:sysctl_net_t,s0) # /proc/sys/net/unix directory and files type sysctl_net_unix_t, sysctl_type; fs_associate(sysctl_net_unix_t) genfscon proc /sys/net/unix gen_context(system_u:object_r:sysctl_net_unix_t,s0) # /proc/sys/vm directory and files type sysctl_vm_t, sysctl_type; fs_associate(sysctl_vm_t) genfscon proc /sys/vm gen_context(system_u:object_r:sysctl_vm_t,s0) # /proc/sys/vm/overcommit_memory type sysctl_vm_overcommit_t, sysctl_type; fs_associate(sysctl_vm_overcommit_t) genfscon proc /sys/vm/overcommit_memory gen_context(system_u:object_r:sysctl_vm_overcommit_t,s0) # /proc/sys/dev directory and files type sysctl_dev_t, sysctl_type; fs_associate(sysctl_dev_t) genfscon proc /sys/dev gen_context(system_u:object_r:sysctl_dev_t,s0) # # unlabeled_t is the type of unlabeled objects. # Objects that have no known labeling information or that # have labels that are no longer valid are treated as having this type. # type unlabeled_t; fs_associate(unlabeled_t) sid unlabeled gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) allow unlabeled_t self:filesystem associate; # Need the following because we are type alias of file_t. files_type(unlabeled_t) kernel_rootfs_mountpoint(unlabeled_t) sid file gen_context(system_u:object_r:unlabeled_t,s0) typealias unlabeled_t alias file_t; neverallow * unlabeled_t:file entrypoint; # anon_inode types type userfaultfd_t; type io_uring_t; # These initial sids are no longer used, and can be removed: sid any_socket gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) sid file_labels gen_context(system_u:object_r:unlabeled_t,s0) sid icmp_socket gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) sid igmp_packet gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) sid init gen_context(system_u:object_r:unlabeled_t,s0) sid kmod gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) sid policy gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) sid scmp_packet gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) sid sysctl_modprobe gen_context(system_u:object_r:unlabeled_t,s0) sid sysctl_fs gen_context(system_u:object_r:unlabeled_t,s0) sid sysctl_kernel gen_context(system_u:object_r:unlabeled_t,s0) sid sysctl_net gen_context(system_u:object_r:unlabeled_t,s0) sid sysctl_net_unix gen_context(system_u:object_r:unlabeled_t,s0) sid sysctl_vm gen_context(system_u:object_r:unlabeled_t,s0) sid sysctl_dev gen_context(system_u:object_r:unlabeled_t,s0) sid tcp_socket gen_context(system_u:object_r:unlabeled_t,mls_systemhigh) ######################################## # # kernel local policy # allow kernel_t self:capability2 ~mac_override; allow kernel_t self:capability ~sys_module; allow kernel_t self:key manage_key_perms; allow kernel_t self:system { ipc_info module_request syslog_console syslog_mod syslog_read }; allow kernel_t self:process ~{ ptrace setcurrent setexec setfscreate setrlimit execmem execstack execheap }; allow kernel_t self:shm create_shm_perms; allow kernel_t self:sem create_sem_perms; allow kernel_t self:msg { send receive }; allow kernel_t self:msgq create_msgq_perms; allow kernel_t self:perf_event manage_perf_event_perms; allow kernel_t self:unix_dgram_socket create_socket_perms; allow kernel_t self:unix_stream_socket create_stream_socket_perms; allow kernel_t self:unix_dgram_socket sendto; allow kernel_t self:unix_stream_socket connectto; allow kernel_t self:fifo_file rw_fifo_file_perms; allow kernel_t self:sock_file read_sock_file_perms; allow kernel_t self:fd use; allow kernel_t self:bpf { map_create map_read map_write prog_load prog_run }; allow kernel_t debugfs_t:dir search_dir_perms; allow kernel_t proc_t:dir list_dir_perms; allow kernel_t proc_t:file read_file_perms; allow kernel_t proc_t:lnk_file read_lnk_file_perms; allow kernel_t proc_net_t:dir list_dir_perms; allow kernel_t proc_net_t:file read_file_perms; allow kernel_t proc_mdstat_t:file read_file_perms; allow kernel_t proc_kcore_t:file getattr; allow kernel_t proc_kmsg_t:file getattr; allow kernel_t sysctl_kernel_t:dir list_dir_perms; allow kernel_t sysctl_kernel_t:file read_file_perms; allow kernel_t sysctl_kernel_ns_last_pid_t:file read_file_perms; allow kernel_t sysctl_t:dir list_dir_perms; # Other possible mount points for the root fs are in files allow kernel_t unlabeled_t:dir mounton; # Kernel-generated traffic e.g., TCP resets on # connections with invalidated labels: allow kernel_t unlabeled_t:packet send; # Allow unlabeled network traffic allow unlabeled_t unlabeled_t:packet { forward_in forward_out }; corenet_in_generic_if(unlabeled_t) corenet_in_generic_node(unlabeled_t) corenet_all_recvfrom_netlabel(kernel_t) # Kernel-generated traffic e.g., ICMP replies: corenet_raw_sendrecv_all_if(kernel_t) corenet_raw_sendrecv_all_nodes(kernel_t) corenet_raw_send_generic_if(kernel_t) # Kernel-generated traffic e.g., TCP resets: corenet_tcp_sendrecv_all_if(kernel_t) corenet_tcp_sendrecv_all_nodes(kernel_t) corenet_raw_send_generic_node(kernel_t) corenet_send_all_packets(kernel_t) corenet_filetrans_all_named_dev(kernel_t) corenet_ib_access_all_pkeys(kernel_t) corenet_ib_access_unlabeled_pkeys(kernel_t) corenet_ib_manage_subnet_all_endports(kernel_t) corenet_ib_manage_subnet_unlabeled_endports(kernel_t) dev_read_sysfs(kernel_t) dev_search_usbfs(kernel_t) # devtmpfs handling: dev_create_generic_dirs(kernel_t) dev_delete_generic_dirs(kernel_t) dev_manage_all_blk_files(kernel_t) dev_manage_all_chr_files(kernel_t) dev_mounton(kernel_t) dev_filetrans_all_named_dev(kernel_t) term_filetrans_all_named_dev(kernel_t) # mapping video devices is needed for plymouthd dev_map_dri(kernel_t) dev_map_framebuffer(kernel_t) fs_getattr_all_fs(kernel_t) # Mount root file system. Used when loading a policy # from initrd, then mounting the root filesystem fs_mount_all_fs(kernel_t) fs_unmount_all_fs(kernel_t) selinux_load_policy(kernel_t) selinux_compute_create_context(kernel_t) term_use_all_terms(kernel_t) term_use_ptmx(kernel_t) corecmd_list_bin(kernel_t) # /proc/sys/kernel/modprobe is set to /bin/true if not using modules, # thus allow a transition into a minimal helper domain through generic bin # types. type kernel_generic_helper_t; domain_type(kernel_generic_helper_t) role system_r types kernel_generic_helper_t; corecmd_bin_entry_type(kernel_generic_helper_t) corecmd_bin_domtrans(kernel_t, kernel_generic_helper_t) allow kernel_generic_helper_t kernel_t:fifo_file read_inherited_fifo_file_perms; # Enable running `/usr/bin/env [u]mount ...` to support ZFS automounting. # See the module/os/linux/zfs/zfs_ctldir.c file in # https://github.com/openzfs/zfs/ for the usermode helper calls. optional_policy(` mount_domtrans(kernel_generic_helper_t) ') domain_use_all_fds(kernel_t) domain_signal_all_domains(kernel_t) domain_search_all_domains_state(kernel_t) domain_connect_all_stream_sockets(kernel_t) domain_rw_all_sockets(kernel_t) # Needed for overlayfs mounter checks # (see: https://bugzilla.redhat.com/show_bug.cgi?id=2215454) domain_obj_id_change_exemption(kernel_t) files_manage_all_files(kernel_t) files_manage_all_blk_files(kernel_t) files_manage_all_chr_files(kernel_t) files_relabel_all_files(kernel_t) # The 'execute' permission on lower inodes is checked against the mounter # cred by overlayfs, so we need to grant it to allow overlay mounts created # during early boot to work. # In itself, this doesn't allow the kernel to execute all files - an # execute_no_trans permission or a type transition is also needed to grant # that ability (and we are much more strict about those). files_mmap_exec_all_files(kernel_t) mcs_process_set_categories(kernel_t) mcs_file_read_all(kernel_t) mcs_file_write_all(kernel_t) mcs_socket_write_all_levels(kernel_t) mls_process_read_up(kernel_t) mls_process_write_down(kernel_t) mls_file_downgrade(kernel_t) mls_file_write_all_levels(kernel_t) mls_file_read_all_levels(kernel_t) mls_socket_write_all_levels(kernel_t) mls_fd_share_all_levels(kernel_t) mls_fd_use_all_levels(kernel_t) mls_process_set_level(kernel_t) ifdef(`distro_redhat',` # Bugzilla 222337 fs_rw_tmpfs_chr_files(kernel_t) ') optional_policy(` abrt_filetrans_named_content(kernel_t) abrt_dump_oops_domtrans(kernel_t) ') optional_policy(` apache_filetrans_home_content(kernel_t) ') optional_policy(` gnome_filetrans_home_content(kernel_t) ') optional_policy(` kerberos_filetrans_home_content(kernel_t) ') optional_policy(` keyutils_request_domtrans(kernel_t) ') optional_policy(` init_dbus_chat(kernel_t) init_sigchld(kernel_t) init_dyntrans(kernel_t) # required actually for plymouthd init_read_state(kernel_t) ') optional_policy(` libs_use_ld_so(kernel_t) libs_use_shared_libs(kernel_t) ') optional_policy(` logging_send_syslog_msg(kernel_t) logging_manage_generic_logs(kernel_t) ') optional_policy(` mta_filetrans_home_content(kernel_t) ') optional_policy(` ssh_filetrans_home_content(kernel_t) ') optional_policy(` storage_filetrans_all_named_dev(kernel_t) ') optional_policy(` userdom_user_home_dir_filetrans_user_home_content(kernel_t, { file dir }) ') optional_policy(` nis_use_ypbind(kernel_t) ') optional_policy(` plymouthd_create_log(kernel_t) plymouthd_filetrans_named_content(kernel_t) ') optional_policy(` # nfs kernel server needs kernel UDP access. It is less risky and painful # to just give it everything. allow kernel_t self:tcp_socket create_stream_socket_perms; allow kernel_t self:udp_socket create_socket_perms; # nfs kernel server needs kernel UDP access. It is less risky and painful # to just give it everything. corenet_udp_sendrecv_generic_if(kernel_t) corenet_udp_sendrecv_generic_node(kernel_t) corenet_udp_sendrecv_all_ports(kernel_t) corenet_udp_bind_generic_node(kernel_t) corenet_sendrecv_portmap_client_packets(kernel_t) corenet_sendrecv_generic_server_packets(kernel_t) auth_dontaudit_getattr_shadow(kernel_t) sysnet_read_config(kernel_t) rpc_udp_rw_nfs_sockets(kernel_t) tunable_policy(`nfs_export_all_ro',` fs_getattr_noxattr_fs(kernel_t) fs_list_noxattr_fs(kernel_t) fs_read_noxattr_fs_files(kernel_t) fs_read_noxattr_fs_symlinks(kernel_t) files_read_non_security_files(kernel_t) ') tunable_policy(`nfs_export_all_rw',` fs_getattr_noxattr_fs(kernel_t) fs_list_noxattr_fs(kernel_t) fs_read_noxattr_fs_files(kernel_t) fs_read_noxattr_fs_symlinks(kernel_t) files_manage_non_security_files(kernel_t) ') ') optional_policy(` seutil_read_config(kernel_t) seutil_read_bin_policy(kernel_t) ') optional_policy(` systemd_coredump_domtrans(kernel_t) # Systemd symlinks /usr/sbin/{poweroff,reboot} (which are invoked by # the kernel to perform an orderly poweroff/reboot) to # /usr/bin/systemctl, so we need to allow the kernel to execute it # and trigger the respective service unit. systemd_systemctl_domain(kernel) systemd_config_power_services(kernel_systemctl_t) systemd_dbus_chat_logind(kernel_systemctl_t) dbus_system_bus_client(kernel_systemctl_t) init_read_utmp(kernel_systemctl_t) ') optional_policy(` virt_filetrans_home_content(kernel_t) ') optional_policy(` xserver_xdm_manage_spool(kernel_t) xserver_filetrans_home_content(kernel_t) ') ######################################## # # Unlabeled process local policy # optional_policy(` # If you load a new policy that removes active domains, processes can # get stuck if you do not allow unlabeled processes to signal init. # If you load an incompatible policy, you should probably reboot, # since you may have compromised system security. init_sigchld(unlabeled_t) ') ######################################## # # Kernel module loading policy # if( ! secure_mode_insmod ) { allow can_load_kernmodule self:capability sys_module; files_load_kernel_modules(can_load_kernmodule) # load_module() calls stop_machine() which # calls sched_setscheduler() allow can_load_kernmodule self:capability sys_nice; kernel_setsched(can_load_kernmodule) } ######################################## # # Rules for unconfined acccess to this module # allow kern_unconfined proc_type:{ file } ~entrypoint; allow kern_unconfined proc_type:dir ~map; allow kern_unconfined proc_type:lnk_file *; allow kern_unconfined sysctl_type:{ file } ~entrypoint; allow kern_unconfined sysctl_type:dir ~map; allow kern_unconfined sysctl_type:lnk_file *; allow kern_unconfined kernel_t:system *; allow kern_unconfined unlabeled_t:dir ~map; allow kern_unconfined unlabeled_t:{ lnk_file sock_file fifo_file chr_file blk_file } *; allow kern_unconfined unlabeled_t:file ~entrypoint; allow kern_unconfined unlabeled_t:filesystem *; allow kern_unconfined unlabeled_t:association *; allow kern_unconfined unlabeled_t:packet *; allow kern_unconfined unlabeled_t:process ~{ ptrace transition dyntransition execmem execstack execheap }; ####################################### # # Kernel system state reader policy # read_files_pattern(kernel_system_state_reader, proc_t, proc_t) read_lnk_files_pattern(kernel_system_state_reader, proc_t, proc_t) list_dirs_pattern(kernel_system_state_reader, proc_t, proc_t)