modules: fix compile error if don't have strict module rwx

commit 93651f80 upstream.

If CONFIG_ARCH_HAS_STRICT_MODULE_RWX is not defined,
we need stub for module_enable_nx() and module_enable_x().

If CONFIG_ARCH_HAS_STRICT_MODULE_RWX is defined, but
CONFIG_STRICT_MODULE_RWX is disabled, we need stub for
module_enable_nx.

Move frob_text() outside of the CONFIG_STRICT_MODULE_RWX,
because it is needed anyway.

Fixes: 2eef1399 ("modules: fix BUG when load module with rodata=n")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel/module.c

@@ -1884,7 +1884,7 @@ static void mod_sysfs_teardown(struct module *mod)
 	mod_sysfs_fini(mod);
 }
 
-#ifdef CONFIG_STRICT_MODULE_RWX
+#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
 /*
  * LKM RO/NX protection: protect module's text/ro-data
  * from modification and any data from execution.
@@ -1907,6 +1907,7 @@ static void frob_text(const struct module_layout *layout,
 		   layout->text_size >> PAGE_SHIFT);
 }
 
+#ifdef CONFIG_STRICT_MODULE_RWX
 static void frob_rodata(const struct module_layout *layout,
 			int (*set_memory)(unsigned long start, int num_pages))
 {
@@ -2039,17 +2040,23 @@ static void disable_ro_nx(const struct module_layout *layout)
 	frob_writable_data(layout, set_memory_x);
 }
 
-#else
+#else /* !CONFIG_STRICT_MODULE_RWX */
 static void disable_ro_nx(const struct module_layout *layout) { }
 static void module_enable_nx(const struct module *mod) { }
 static void module_disable_nx(const struct module *mod) { }
-#endif
+#endif /*  CONFIG_STRICT_MODULE_RWX */
 
 static void module_enable_x(const struct module *mod)
 {
 	frob_text(&mod->core_layout, set_memory_x);
 	frob_text(&mod->init_layout, set_memory_x);
 }
+#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
+static void disable_ro_nx(const struct module_layout *layout) { }
+static void module_enable_nx(const struct module *mod) { }
+static void module_disable_nx(const struct module *mod) { }
+static void module_enable_x(const struct module *mod) { }
+#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
 
 #ifdef CONFIG_LIVEPATCH
 /*