tomoyo: Check address length before reading address family

KMSAN will complain if valid address length passed to bind()/connect()/
sendmsg() is shorter than sizeof("struct sockaddr"->sa_family) bytes.

Signed-off-by: Tetsuo Handa <[e-mail]>
Signed-off-by: James Morris <[e-mail]>

security/tomoyo/network.c

···
 {
 	struct tomoyo_inet_addr_info *i = &address->inet;
 
+	if (addr_len < offsetofend(struct sockaddr, sa_family))
+		return 0;
 	switch (addr->sa_family) {
 	case AF_INET6:
 		if (addr_len < SIN6_LEN_RFC2133)
···
 {
 	struct tomoyo_unix_addr_info *u = &address->unix0;
 
+	if (addr_len < offsetofend(struct sockaddr, sa_family))
+		return 0;
 	if (addr->sa_family != AF_UNIX)
 		return 0;
 	u->addr = ((struct sockaddr_un *) addr)->sun_path;