From: Matthew Garrett <matthew.garr...@nebula.com>

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 the
kernel is locked down.

Signed-off-by: Matthew Garrett <matthew.garr...@nebula.com>
Signed-off-by: David Howells <dhowe...@redhat.com>
Reviewed-by: "Lee, Chun-Yi" <j...@suse.com>
cc: acpi4asus-u...@lists.sourceforge.net
cc: platform-driver-...@vger.kernel.org
---

 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 48e1541dc8d4..ef5587469337 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -1905,6 +1905,9 @@ static int show_dsts(struct seq_file *m, void *data)
        int err;
        u32 retval = -1;
 
+       if (kernel_is_locked_down("Asus WMI"))
+               return -EPERM;
+
        err = asus_wmi_get_devstate(asus, asus->debug.dev_id, &retval);
 
        if (err < 0)
@@ -1921,6 +1924,9 @@ static int show_devs(struct seq_file *m, void *data)
        int err;
        u32 retval = -1;
 
+       if (kernel_is_locked_down("Asus WMI"))
+               return -EPERM;
+
        err = asus_wmi_set_devstate(asus->debug.dev_id, asus->debug.ctrl_param,
                                    &retval);
 
@@ -1945,6 +1951,9 @@ static int show_call(struct seq_file *m, void *data)
        union acpi_object *obj;
        acpi_status status;
 
+       if (kernel_is_locked_down("Asus WMI"))
+               return -EPERM;
+
        status = wmi_evaluate_method(ASUS_WMI_MGMT_GUID,
                                     0, asus->debug.method_id,
                                     &input, &output);

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