CVE-2023-53356

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