calipso: Don't call calipso functions for AF_INET sk.
In the Linux kernel, the following vulnerability has been resolved: calipso: Don't call calipso functions for AF_INET sk. syzkaller reported a null-ptr-deref in txopt_get(). [0] The offset 0x70 was of struct ipv6_txoptions in struct ipv6_pinfo, so struct ipv6_pinfo was NULL there. However, this never happens for IPv6 sockets as inet_sk(sk)->pinet6 is always set in inet6_create(), meaning the socket was not IPv6 one. The root cause is missing validation in netlbl_conn_setattr(). netlbl_conn_setattr() switches branches based on struct sockaddr.sa_family, which is passed from userspace. However, netlbl_conn_setattr() does not check if the