Revert "Revert "Add neverallows for debugfs access""

This reverts commit e95e0ec0a5.

Now that b/186727553 is fixed, it should be safe to revert this revert.

Test: build
Bug: 184381659
Change-Id: Ibea3882296db880f5cafe4f9efa36d79a183c8a1

private/coredomain.te

@@ -153,9 +153,11 @@ full_treble_only(`
   # debugfs
   neverallow {
     coredomain
-    -dumpstate
-    -init
-    -system_server
+    no_debugfs_restriction(`
+      -dumpstate
+      -init
+      -system_server
+    ')
   } debugfs:file no_rw_file_perms;
 
   # tracefs

private/domain.te

@@ -521,3 +521,18 @@ neverallow {
   -traced_probes
   -traced_perf
 } proc_kallsyms:file { open read };
+
+# debugfs_kcov type is not included in this neverallow statement since the KCOV
+# tool uses it for kernel fuzzing.
+enforce_debugfs_restriction(`
+  neverallow {
+    domain
+    userdebug_or_eng(`
+      -init
+      -hal_dumpstate
+    ')
+  } { debugfs_type
+      userdebug_or_eng(`-debugfs_kcov')
+      -tracefs_type
+  }:file no_rw_file_perms;
+')

private/dumpstate.te

@@ -54,7 +54,10 @@ allow dumpstate {
 }:process signal;
 
 # For collecting bugreports.
-allow dumpstate debugfs_wakeup_sources:file r_file_perms;
+no_debugfs_restriction(`
+  allow dumpstate debugfs_wakeup_sources:file r_file_perms;
+')
+
 allow dumpstate dev_type:blk_file getattr;
 allow dumpstate webview_zygote:process signal;
 allow dumpstate sysfs_dmabuf_stats:file r_file_perms;

private/incidentd.te

@@ -29,7 +29,9 @@ unix_socket_send(incidentd, statsdw, statsd)
 allow incidentd proc_pagetypeinfo:file r_file_perms;
 
 # section id 2002, allow reading /d/wakeup_sources
-allow incidentd debugfs_wakeup_sources:file r_file_perms;
+no_debugfs_restriction(`
+  allow incidentd debugfs_wakeup_sources:file r_file_perms;
+')
 
 # section id 2003, allow executing top
 allow incidentd proc_meminfo:file { open read };

private/storaged.te

@@ -18,10 +18,12 @@ allow storaged packages_list_file:file r_file_perms;
 allow storaged storaged_data_file:dir rw_dir_perms;
 allow storaged storaged_data_file:file create_file_perms;
 
-userdebug_or_eng(`
-  # Read access to debugfs
-  allow storaged debugfs_mmc:dir search;
-  allow storaged debugfs_mmc:file r_file_perms;
+no_debugfs_restriction(`
+  userdebug_or_eng(`
+    # Read access to debugfs
+    allow storaged debugfs_mmc:dir search;
+    allow storaged debugfs_mmc:file r_file_perms;
+  ')
 ')
 
 # Needed to provide debug dump output via dumpsys pipes.

private/system_server.te

@@ -184,7 +184,9 @@ allow system_server stats_data_file:dir { open read remove_name search write };
 allow system_server stats_data_file:file unlink;
 
 # Read /sys/kernel/debug/wakeup_sources.
-allow system_server debugfs_wakeup_sources:file r_file_perms;
+no_debugfs_restriction(`
+  allow system_server debugfs_wakeup_sources:file r_file_perms;
+')
 
 # Read /sys/kernel/ion/*.
 allow system_server sysfs_ion:file r_file_perms;

public/attributes

@@ -62,6 +62,9 @@ attribute sysfs_type;
 # All types use for debugfs files.
 attribute debugfs_type;
 
+# All types used for tracefs files.
+attribute tracefs_type;
+
 # Attribute used for all sdcards
 attribute sdcard_type;
 

public/dumpstate.te

@@ -113,10 +113,12 @@ allow dumpstate {
 }:file r_file_perms;
 
 # Other random bits of data we want to collect
-allow dumpstate debugfs:file r_file_perms;
-auditallow dumpstate debugfs:file r_file_perms;
+no_debugfs_restriction(`
+  allow dumpstate debugfs:file r_file_perms;
+  auditallow dumpstate debugfs:file r_file_perms;
 
-allow dumpstate debugfs_mmc:file r_file_perms;
+  allow dumpstate debugfs_mmc:file r_file_perms;
+')
 
 # df for
 allow dumpstate {

public/file.te

@@ -144,14 +144,14 @@ type exfat, sdcard_type, fs_type, mlstrustedobject;
 type debugfs, fs_type, debugfs_type;
 type debugfs_kprobes, fs_type, debugfs_type;
 type debugfs_mmc, fs_type, debugfs_type;
-type debugfs_mm_events_tracing, fs_type, debugfs_type;
-type debugfs_trace_marker, fs_type, debugfs_type, mlstrustedobject;
-type debugfs_tracing, fs_type, debugfs_type, mlstrustedobject;
-type debugfs_tracing_debug, fs_type, debugfs_type, mlstrustedobject;
-type debugfs_tracing_instances, fs_type, debugfs_type;
-type debugfs_tracing_printk_formats, fs_type, debugfs_type;
+type debugfs_mm_events_tracing, fs_type, debugfs_type, tracefs_type;
+type debugfs_trace_marker, fs_type, debugfs_type, mlstrustedobject, tracefs_type;
+type debugfs_tracing, fs_type, debugfs_type, mlstrustedobject, tracefs_type;
+type debugfs_tracing_debug, fs_type, debugfs_type, mlstrustedobject, tracefs_type;
+type debugfs_tracing_instances, fs_type, debugfs_type, tracefs_type;
+type debugfs_tracing_printk_formats, fs_type, debugfs_type, tracefs_type;
 type debugfs_wakeup_sources, fs_type, debugfs_type;
-type debugfs_wifi_tracing, fs_type, debugfs_type;
+type debugfs_wifi_tracing, fs_type, debugfs_type, tracefs_type;
 type securityfs, fs_type;
 
 type pstorefs, fs_type;
@@ -562,7 +562,7 @@ type hwservice_contexts_file, system_file_type, file_type;
 type vndservice_contexts_file, file_type;
 
 # /sys/kernel/tracing/instances/bootreceiver for monitoring kernel memory corruptions.
-type debugfs_bootreceiver_tracing, fs_type, debugfs_type;
+type debugfs_bootreceiver_tracing, fs_type, debugfs_type, tracefs_type;
 
 # kernel modules
 type vendor_kernel_modules, vendor_file_type, file_type;

public/init.te

@@ -240,8 +240,11 @@ allow init {
   -system_file_type
   -vendor_file_type
   -vold_data_file
+  enforce_debugfs_restriction(`-debugfs_type')
 }:file { create getattr open read write setattr relabelfrom unlink map };
 
+allow init tracefs_type:file { create_file_perms relabelfrom };
+
 allow init {
   file_type
   -app_data_file
@@ -290,8 +293,8 @@ allow init {
   -privapp_data_file
 }:dir_file_class_set relabelto;
 
-allow init { sysfs debugfs debugfs_tracing debugfs_tracing_debug }:{ dir file lnk_file } { getattr relabelfrom };
-allow init { sysfs_type debugfs_type }:{ dir file lnk_file } { relabelto getattr };
+allow init { sysfs no_debugfs_restriction(`debugfs') debugfs_tracing debugfs_tracing_debug }:{ dir file lnk_file } { getattr relabelfrom };
+allow init { sysfs_type no_debugfs_restriction(`debugfs_type') tracefs_type }:{ dir file lnk_file } { relabelto getattr };
 allow init dev_type:dir create_dir_perms;
 allow init dev_type:lnk_file create;
 
@@ -312,6 +315,7 @@ allow init {
   -sdcard_type
   -sysfs_type
   -rootfs
+  enforce_debugfs_restriction(`-debugfs_type')
 }:file { open read setattr };
 allow init { fs_type -contextmount_type -sdcard_type -rootfs }:dir  { open read setattr search };
 

public/vendor_init.te

@@ -79,6 +79,7 @@ allow vendor_init {
   -apex_metadata_file
   -apex_info_file
   -userspace_reboot_metadata_file
+  enforce_debugfs_restriction(`-debugfs_type')
 }:file { create getattr open read write setattr relabelfrom unlink map };
 
 allow vendor_init {
@@ -143,8 +144,11 @@ allow vendor_init {
   -proc_uid_time_in_state
   -proc_uid_concurrent_active_time
   -proc_uid_concurrent_policy_time
+  enforce_debugfs_restriction(`-debugfs_type')
 }:file { open read setattr map };
 
+allow vendor_init tracefs_type:file { open read setattr map };
+
 allow vendor_init {
   fs_type
   -contextmount_type