usb: gadget: f_hid: fix report descriptor allocation

commit 61890dc28f7d9e9aac8a9471302613824c22fae4 upstream.

The commit 89ff3dfac604 ("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: 89ff3dfac604 ("usb: gadget: f_hid: fix f_hidg lifetime vs cdev")
Cc: stable@vger.kernel.org
Signed-off-by: Konstantin Aladyshev <aladyshev22@gmail.com>
Link: https://lore.kernel.org/r/20231206080744.253-2-aladyshev22@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_hid.c b/drivers/usb/gadget/function/f_hid.c
index ea85e2c..3c8a9dd 100644 (file)
--- a/drivers/usb/gadget/function/f_hid.c
+++ b/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;