The driver was doing a synchronous uninterruptible bulk-transfer without using a timeout. This could lead to the driver hanging on probe due to a malfunctioning (or malicious) device until the device is physically disconnected. While sleeping in probe the driver prevents other devices connected to the same hub from being added to (or removed from) the bus.
An arbitrary limit of five seconds should be more than enough.
Fixes: dbafc28955fa ("NFC: pn533: don't send USB data off of the stack") Cc: stable stable@vger.kernel.org # 4.18 Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Johan Hovold johan@kernel.org --- drivers/nfc/pn533/usb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/nfc/pn533/usb.c b/drivers/nfc/pn533/usb.c index 4590fbf82dc2..f5bb7ace2ff5 100644 --- a/drivers/nfc/pn533/usb.c +++ b/drivers/nfc/pn533/usb.c @@ -391,7 +391,7 @@ static int pn533_acr122_poweron_rdr(struct pn533_usb_phy *phy) cmd, sizeof(cmd), false);
rc = usb_bulk_msg(phy->udev, phy->out_urb->pipe, buffer, sizeof(cmd), - &transferred, 0); + &transferred, 5000); kfree(buffer); if (rc || (transferred != sizeof(cmd))) { nfc_err(&phy->udev->dev,