[PATCH 13/27] asus-wmi: Restrict debugfs interface when the kernel is locked down
From: dhowells@redhat.com (David Howells)
Date: 2017-10-19 14:52:17
Also in:
linux-efi, lkml
Subsystem:
asus notebooks and eeepc acpi/wmi extras drivers, the rest, x86 platform drivers · Maintainers:
Corentin Chary, Luke D. Jones, Denis Benato, Linus Torvalds, Hans de Goede, Ilpo Järvinen
From: Matthew Garrett <redacted> 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 <redacted> Signed-off-by: David Howells <dhowells@redhat.com> cc: acpi4asus-user at lists.sourceforge.net cc: platform-driver-x86 at 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); --
To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html