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

From: Yang Yingliang
Date: Tue Jun 25 2019 - 05:21:15 EST


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.

Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
kernel/module.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/kernel/module.c b/kernel/module.c
index c3ae34c..cfff441 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1875,7 +1875,7 @@ 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.
@@ -1898,6 +1898,7 @@ 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))
{
@@ -2010,15 +2011,19 @@ void set_all_modules_text_ro(void)
}
mutex_unlock(&module_mutex);
}
-#else
+#else /* !CONFIG_STRICT_MODULE_RWX */
static void module_enable_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 module_enable_nx(const struct module *mod) { }
+static void module_enable_x(const struct module *mod) { }
+#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
+

#ifdef CONFIG_LIVEPATCH
/*
--
1.8.3