usb: gadget: f_hid: fix report descriptor allocation

The commit 89ff3df ("usb: gadget: f_hid: fix f_hidg lifetime vs
cdev") has introduced a bug that leads to hid device corruption after
the replug operation.
Reverse device managed memory allocation for the report descriptor
to fix the issue.

Tested:
This change was tested on the AMD EthanolX CRB server with the BMC
based on the OpenBMC distribution. The BMC provides KVM functionality
via the USB gadget device:
- before: KVM page refresh results in a broken USB device,
- after: KVM page refresh works without any issues.

Fixes: 89ff3df ("usb: gadget: f_hid: fix f_hidg lifetime vs cdev")
Cc: [email protected]
Signed-off-by: Konstantin Aladyshev <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Kostr

drivers/usb/gadget/function/f_hid.c

@@ -92,6 +92,7 @@ static void hidg_release(struct device *dev)
 {
 	struct f_hidg *hidg = container_of(dev, struct f_hidg, dev);
 
+	kfree(hidg->report_desc);
 	kfree(hidg->set_report_buf);
 	kfree(hidg);
 }
@@ -1287,9 +1288,9 @@ static struct usb_function *hidg_alloc(struct usb_function_instance *fi)
 	hidg->report_length = opts->report_length;
 	hidg->report_desc_length = opts->report_desc_length;
 	if (opts->report_desc) {
-		hidg->report_desc = devm_kmemdup(&hidg->dev, opts->report_desc,
-						 opts->report_desc_length,
-						 GFP_KERNEL);
+		hidg->report_desc = kmemdup(opts->report_desc,
+					    opts->report_desc_length,
+					    GFP_KERNEL);
 		if (!hidg->report_desc) {
 			ret = -ENOMEM;
 			goto err_put_device;