selinux: distinguish non-init user namespace capability checks

Distinguish capability checks against a target associated
with the init user namespace versus capability checks against
a target associated with a non-init user namespace by defining
and using separate security classes for the latter.

This is needed to support e.g. Chrome usage of user namespaces
for the Chrome sandbox without needing to allow Chrome to also
exercise capabilities on targets in the init user namespace.

Suggested-by: Dan Walsh <[email protected]>
Signed-off-by: Stephen Smalley <[email protected]>
Signed-off-by: Paul Moore <[email protected]>
diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
index 8fbd138..1f1f4b2 100644
--- a/security/selinux/include/classmap.h
+++ b/security/selinux/include/classmap.h
@@ -12,6 +12,18 @@
 #define COMMON_IPC_PERMS "create", "destroy", "getattr", "setattr", "read", \
 	    "write", "associate", "unix_read", "unix_write"
 
+#define COMMON_CAP_PERMS  "chown", "dac_override", "dac_read_search", \
+	    "fowner", "fsetid", "kill", "setgid", "setuid", "setpcap", \
+	    "linux_immutable", "net_bind_service", "net_broadcast", \
+	    "net_admin", "net_raw", "ipc_lock", "ipc_owner", "sys_module", \
+	    "sys_rawio", "sys_chroot", "sys_ptrace", "sys_pacct", "sys_admin", \
+	    "sys_boot", "sys_nice", "sys_resource", "sys_time", \
+	    "sys_tty_config", "mknod", "lease", "audit_write", \
+	    "audit_control", "setfcap"
+
+#define COMMON_CAP2_PERMS  "mac_override", "mac_admin", "syslog", \
+		"wake_alarm", "block_suspend", "audit_read"
+
 /*
  * Note: The name for any socket class should be suffixed by "socket",
  *	 and doesn't contain more than one substr of "socket".
@@ -34,14 +46,7 @@
 	  { "ipc_info", "syslog_read", "syslog_mod",
 	    "syslog_console", "module_request", "module_load", NULL } },
 	{ "capability",
-	  { "chown", "dac_override", "dac_read_search",
-	    "fowner", "fsetid", "kill", "setgid", "setuid", "setpcap",
-	    "linux_immutable", "net_bind_service", "net_broadcast",
-	    "net_admin", "net_raw", "ipc_lock", "ipc_owner", "sys_module",
-	    "sys_rawio", "sys_chroot", "sys_ptrace", "sys_pacct", "sys_admin",
-	    "sys_boot", "sys_nice", "sys_resource", "sys_time",
-	    "sys_tty_config", "mknod", "lease", "audit_write",
-	    "audit_control", "setfcap", NULL } },
+	  { COMMON_CAP_PERMS, NULL } },
 	{ "filesystem",
 	  { "mount", "remount", "unmount", "getattr",
 	    "relabelfrom", "relabelto", "associate", "quotamod",
@@ -150,12 +155,15 @@
 	{ "memprotect", { "mmap_zero", NULL } },
 	{ "peer", { "recv", NULL } },
 	{ "capability2",
-	  { "mac_override", "mac_admin", "syslog", "wake_alarm", "block_suspend",
-	    "audit_read", NULL } },
+	  { COMMON_CAP2_PERMS, NULL } },
 	{ "kernel_service", { "use_as_override", "create_files_as", NULL } },
 	{ "tun_socket",
 	  { COMMON_SOCK_PERMS, "attach_queue", NULL } },
 	{ "binder", { "impersonate", "call", "set_context_mgr", "transfer",
 		      NULL } },
+	{ "cap_userns",
+	  { COMMON_CAP_PERMS, NULL } },
+	{ "cap2_userns",
+	  { COMMON_CAP2_PERMS, NULL } },
 	{ NULL }
   };