| Message ID | 20220412165055.257113-1-dossche.niels@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | usb: usbip: add missing device lock on tweak configuration cmd | expand |
diff --git a/drivers/usb/usbip/stub_rx.c b/drivers/usb/usbip/stub_rx.c index 325c22008e53..5dd41e8215e0 100644 --- a/drivers/usb/usbip/stub_rx.c +++ b/drivers/usb/usbip/stub_rx.c @@ -138,7 +138,9 @@ static int tweak_set_configuration_cmd(struct urb *urb) req = (struct usb_ctrlrequest *) urb->setup_packet; config = le16_to_cpu(req->wValue); + usb_lock_device(sdev->udev); err = usb_set_configuration(sdev->udev, config); + usb_unlock_device(sdev->udev); if (err && err != -ENODEV) dev_err(&sdev->udev->dev, "can't set config #%d, error %d\n", config, err);
The function documentation of usb_set_configuration says that its callers should hold the device lock. This lock is held for all callsites except tweak_set_configuration_cmd. The code path can be executed for example when attaching a remote USB device. The solution is to surround the call by the device lock. This bug was found using my experimental own-developed static analysis tool, which reported the missing lock on v5.17.2. I manually verified this bug report by doing code review as well. I runtime checked that the required lock is not held. I compiled and runtime tested this on x86_64 with a USB mouse. After applying this patch, my analyser no longer reports this potential bug. Fixes: 2c8c98158946 ("staging: usbip: let client choose device configuration") Signed-off-by: Niels Dossche <dossche.niels@gmail.com> --- I'm developing this tool as part of my master's dissertation in order to obtain my master's degree. If you'd like more information about the details of the tool, please let me know. drivers/usb/usbip/stub_rx.c | 2 ++ 1 file changed, 2 insertions(+)