smack: 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.

Also, since smk_ipv6_port_label()/smack_netlabel_send()/
smack_ipv6host_label()/smk_ipv6_check()/smk_ipv6_port_check() are not
checking valid address length and/or address family, make sure we check
both. The minimal valid length in smack_socket_connect() is changed from
sizeof(struct sockaddr_in6) bytes to SIN6_LEN_RFC2133 bytes, for it seems
that Smack is not using "struct sockaddr_in6"->sin6_scope_id field.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
This commit is contained in:
Tetsuo Handa 2019-04-12 19:59:35 +09:00 committed by Casey Schaufler
parent f7450bc6e7
commit b9ef5513c9

View File

@ -2806,13 +2806,17 @@ static int smack_socket_socketpair(struct socket *socka,
*
* Records the label bound to a port.
*
* Returns 0
* Returns 0 on success, and error code otherwise
*/
static int smack_socket_bind(struct socket *sock, struct sockaddr *address,
int addrlen)
{
if (sock->sk != NULL && sock->sk->sk_family == PF_INET6)
if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) {
if (addrlen < SIN6_LEN_RFC2133 ||
address->sa_family != AF_INET6)
return -EINVAL;
smk_ipv6_port_label(sock, address);
}
return 0;
}
#endif /* SMACK_IPV6_PORT_LABELING */
@ -2848,12 +2852,13 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
switch (sock->sk->sk_family) {
case PF_INET:
if (addrlen < sizeof(struct sockaddr_in))
if (addrlen < sizeof(struct sockaddr_in) ||
sap->sa_family != AF_INET)
return -EINVAL;
rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap);
break;
case PF_INET6:
if (addrlen < sizeof(struct sockaddr_in6))
if (addrlen < SIN6_LEN_RFC2133 || sap->sa_family != AF_INET6)
return -EINVAL;
#ifdef SMACK_IPV6_SECMARK_LABELING
rsp = smack_ipv6host_label(sip);
@ -3683,9 +3688,15 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
switch (sock->sk->sk_family) {
case AF_INET:
if (msg->msg_namelen < sizeof(struct sockaddr_in) ||
sip->sin_family != AF_INET)
return -EINVAL;
rc = smack_netlabel_send(sock->sk, sip);
break;
case AF_INET6:
if (msg->msg_namelen < SIN6_LEN_RFC2133 ||
sap->sin6_family != AF_INET6)
return -EINVAL;
#ifdef SMACK_IPV6_SECMARK_LABELING
rsp = smack_ipv6host_label(sap);
if (rsp != NULL)