In the Linux kernel, the following vulnerability has been resolved: usb: gadget: userial: Add null pointer check in gserialsuspend Consider a case where gserialdisconnect has already cleared gser->ioport. And if gserialsuspend gets called afterwards, it will lead to accessing of gser->ioport and thus causing null pointer dereference. Avoid this by adding a null pointer check. Added a static spinlock to prevent gser->ioport from becoming null after the newly added null pointer check.