usbserial -d may be called more than once, which now results in removal
of a driver that may already be removed leading to double frees.
usbgadget -d doesn't suffer from this as both usb_multi_register and
usb_multi_unregister keep around a global variable to check if the
gadget is currently registered. Let's do likewise for usb_serial_unregister.
Fixes: 14211ab8b0e1 ("usb: gadget: Update core to Linux-6.3-rc2")
Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
---
drivers/usb/gadget/legacy/serial.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/gadget/legacy/serial.c b/drivers/usb/gadget/legacy/serial.c
index 46c41f6dea30..913d174a9177 100644
--- a/drivers/usb/gadget/legacy/serial.c
+++ b/drivers/usb/gadget/legacy/serial.c
@@ -247,8 +247,17 @@ static struct usb_composite_driver gserial_driver = {
.unbind = gs_unbind,
};
+static bool usb_serial_registered;
+
int usb_serial_register(struct usb_serial_pdata *pdata)
{
+ int ret;
+
+ if (usb_serial_registered) {
+ pr_err("USB serial gadget already registered\n");
+ return -EBUSY;
+ }
+
/* We *could* export two configs; that'd be much cleaner...
* but neither of these product IDs was defined that way.
*/
@@ -273,10 +282,18 @@ int usb_serial_register(struct usb_serial_pdata *pdata)
device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC;
}
- return usb_composite_probe(&gserial_driver);
+ ret = usb_composite_probe(&gserial_driver);
+ if (!ret)
+ usb_serial_registered = true;
+
+ return ret;
}
void usb_serial_unregister(void)
{
+ if (!usb_serial_registered)
+ return;
+
usb_composite_unregister(&gserial_driver);
+ usb_serial_registered = false;
}
--
2.39.2
