From 968ccfb32df5d5c9673c57641ebf90b25c0df880 Mon Sep 17 00:00:00 2001
From: Matthew Garrett <matthew.garrett(a)nebula.com>
Date: Mon, 19 Aug 2013 13:26:06 -0400
Subject: [PATCH 05/13] asus-wmi: Restrict debugfs interface when module
loading is restricted
We have no way of validating what all of the Asus WMI methods do on a
given machine, and there's a risk that some will allow hardware state to
be manipulated in such a way that arbitrary code can be executed in the
kernel, circumventing module loading restrictions. Prevent that if any of
these features are enabled.
Signed-off-by: Matthew Garrett <matthew.garrett(a)nebula.com>
---
drivers/platform/x86/asus-wmi.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 19c313b..db18ef66 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -1618,6 +1618,9 @@ static int show_dsts(struct seq_file *m, void *data)
int err;
u32 retval = -1;
+ if (secure_modules())
+ return -EPERM;
+
err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval);
if (err < 0)
@@ -1634,6 +1637,9 @@ static int show_devs(struct seq_file *m, void *data)
int err;
u32 retval = -1;
+ if (secure_modules())
+ return -EPERM;
+
err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param,
&retval);
@@ -1658,6 +1664,9 @@ static int show_call(struct seq_file *m, void *data)
union acpi_object *obj;
acpi_status status;
+ if (secure_modules())
+ return -EPERM;
+
status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID,
1, asus->debug.method_id,
&input, &output);
--
1.8.3.1