CVE-2023-53809

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> l2tp: Avoid possible recursive deadlock in l2tp_tunnel_register()<br /> <br /> When a file descriptor of pppol2tp socket is passed as file descriptor<br /> of UDP socket, a recursive deadlock occurs in l2tp_tunnel_register().<br /> This situation is reproduced by the following program:<br /> <br /> int main(void)<br /> {<br /> int sock;<br /> struct sockaddr_pppol2tp addr;<br /> <br /> sock = socket(AF_PPPOX, SOCK_DGRAM, PX_PROTO_OL2TP);<br /> if (sock