HID: logitech-hidpp: Guard FF init code against non-USB devices

commit 0e13e7b448005612972eae36c0f698c21d1e2f8a upstream.

The Force Feedback code assumes that all the devices passed to it will
be USB devices, but that might not be the case for emulated devices.
Guard against a crash by checking the device type before poking at USB
properties.

Cc: stable@vger.kernel.org # v5.16+
Reported-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20221215154416.111704-1-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index 68f9e9d207f42ba21a3607c56eb2a4fc365ed0e7..ba14b6f69ff7a55b49cdf76936ede032db1696bf 100644 (file)
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -2545,12 +2545,17 @@ static int hidpp_ff_init(struct hidpp_device *hidpp,
        struct hid_device *hid = hidpp->hid_dev;
        struct hid_input *hidinput;
        struct input_dev *dev;
-       const struct usb_device_descriptor *udesc = &(hid_to_usb_dev(hid)->descriptor);
-       const u16 bcdDevice = le16_to_cpu(udesc->bcdDevice);
+       struct usb_device_descriptor *udesc;
+       u16 bcdDevice;
        struct ff_device *ff;
        int error, j, num_slots = data->num_effects;
        u8 version;
 
+       if (!hid_is_usb(hid)) {
+               hid_err(hid, "device is not USB\n");
+               return -ENODEV;
+       }
+
        if (list_empty(&hid->inputs)) {
                hid_err(hid, "no inputs found\n");
                return -ENODEV;
@@ -2564,6 +2569,8 @@ static int hidpp_ff_init(struct hidpp_device *hidpp,
        }
 
        /* Get firmware release */
+       udesc = &(hid_to_usb_dev(hid)->descriptor);
+       bcdDevice = le16_to_cpu(udesc->bcdDevice);
        version = bcdDevice & 255;
 
        /* Set supported force feedback capabilities */