int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
{
int rc = NET_RX_SUCCESS;
if (sk_filter(sk, skb))
goto discard_and_relse;
skb->dev = NULL;
if (nested)
bh_lock_sock_nested(sk);
else
bh_lock_sock(sk);
if (!sock_owned_by_user(sk)) {
/*
* trylock + unlock semantics:
*/
mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
rc = sk->sk_backlog_rcv(sk, skb);
mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
} else
sk_add_backlog(sk, skb);
bh_unlock_sock(sk);
out:
sock_put(sk);
return rc;
discard_and_relse:
kfree_skb(skb);
goto out;
}
/**
* selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled
* @inode: the file descriptor's inode
* @mask: the permission mask
*
* Description:
* Looks at a file's inode and if it is marked as a socket protected by
* NetLabel then verify that the socket has been labeled, if not try to label
* the socket now with the inode's SID. Returns zero on success, negative
* values on failure.
*
*/
int selinux_netlbl_inode_permission(struct inode *inode, int mask)
{
int rc;
struct sock *sk;
struct socket *sock;
struct sk_security_struct *sksec;
if (!S_ISSOCK(inode->i_mode) ||
((mask & (MAY_WRITE | MAY_APPEND)) == 0))
return 0;
sock = SOCKET_I(inode);
sk = sock->sk;
sksec = sk->sk_security;
if (sksec->nlbl_state != NLBL_REQUIRE)
return 0;
local_bh_disable();
bh_lock_sock_nested(sk);
if (likely(sksec->nlbl_state == NLBL_REQUIRE))
rc = selinux_netlbl_sock_setsid(sk);
else
rc = 0;
bh_unlock_sock(sk);
local_bh_enable();
return rc;
}
/**
* selinux_netlbl_socket_connect - Label a client-side socket on connect
* @sk: the socket to label
* @addr: the destination address
*
* Description:
* Attempt to label a connected socket with NetLabel using the given address.
* Returns zero values on success, negative values on failure.
*
*/
int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr)
{
int rc;
struct sk_security_struct *sksec = sk->sk_security;
struct netlbl_lsm_secattr *secattr;
if (sksec->nlbl_state != NLBL_REQSKB &&
sksec->nlbl_state != NLBL_CONNLABELED)
return 0;
local_bh_disable();
bh_lock_sock_nested(sk);
/* connected sockets are allowed to disconnect when the address family
* is set to AF_UNSPEC, if that is what is happening we want to reset
* the socket */
if (addr->sa_family == AF_UNSPEC) {
netlbl_sock_delattr(sk);
sksec->nlbl_state = NLBL_REQSKB;
rc = 0;
goto socket_connect_return;
}
secattr = selinux_netlbl_sock_genattr(sk);
if (secattr == NULL) {
rc = -ENOMEM;
goto socket_connect_return;
}
rc = netlbl_conn_setattr(sk, addr, secattr);
if (rc == 0)
sksec->nlbl_state = NLBL_CONNLABELED;
socket_connect_return:
bh_unlock_sock(sk);
local_bh_enable();
return rc;
}