In the Linux kernel, the following vulnerability has been resolved:
netlabel: Fix NULL pointer exception caused by CALIPSO on IPv4 sockets
When calling netlblconnsetattr(), addr->safamily is used to determine the function behavior. If sk is an IPv4 socket, but the connect function is called with an IPv6 address, the function calipsosock_setattr() is triggered. Inside this function, the following code is executed:
skfullsock(sk) ? inetsk(sk)->pinet6 : NULL;
Since sk is an IPv4 socket, pinet6 is NULL, leading to a null pointer dereference.
This patch fixes the issue by checking if inet6_sk(sk) returns a NULL pointer before accessing pinet6.