linux/net/nfc/llcp_sock.c
Or Cohen c61760e694 net/nfc: fix use-after-free llcp_sock_bind/connect
Commits 8a4cd82d ("nfc: fix refcount leak in llcp_sock_connect()")
and c33b1cc62 ("nfc: fix refcount leak in llcp_sock_bind()")
fixed a refcount leak bug in bind/connect but introduced a
use-after-free if the same local is assigned to 2 different sockets.

This can be triggered by the following simple program:
    int sock1 = socket( AF_NFC, SOCK_STREAM, NFC_SOCKPROTO_LLCP );
    int sock2 = socket( AF_NFC, SOCK_STREAM, NFC_SOCKPROTO_LLCP );
    memset( &addr, 0, sizeof(struct sockaddr_nfc_llcp) );
    addr.sa_family = AF_NFC;
    addr.nfc_protocol = NFC_PROTO_NFC_DEP;
    bind( sock1, (struct sockaddr*) &addr, sizeof(struct sockaddr_nfc_llcp) )
    bind( sock2, (struct sockaddr*) &addr, sizeof(struct sockaddr_nfc_llcp) )
    close(sock1);
    close(sock2);

Fix this by assigning NULL to llcp_sock->local after calling
nfc_llcp_local_put.

This addresses CVE-2021-23134.

Reported-by: Or Cohen <orcohen@paloaltonetworks.com>
Reported-by: Nadav Markus <nmarkus@paloaltonetworks.com>
Fixes: c33b1cc62 ("nfc: fix refcount leak in llcp_sock_bind()")
Signed-off-by: Or Cohen <orcohen@paloaltonetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-04 11:59:48 -07:00

1055 lines
22 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2011 Intel Corporation. All rights reserved.
*/
#define pr_fmt(fmt) "llcp: %s: " fmt, __func__
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/nfc.h>
#include <linux/sched/signal.h>
#include "nfc.h"
#include "llcp.h"
static int sock_wait_state(struct sock *sk, int state, unsigned long timeo)
{
DECLARE_WAITQUEUE(wait, current);
int err = 0;
pr_debug("sk %p", sk);
add_wait_queue(sk_sleep(sk), &wait);
set_current_state(TASK_INTERRUPTIBLE);
while (sk->sk_state != state) {
if (!timeo) {
err = -EINPROGRESS;
break;
}
if (signal_pending(current)) {
err = sock_intr_errno(timeo);
break;
}
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock(sk);
set_current_state(TASK_INTERRUPTIBLE);
err = sock_error(sk);
if (err)
break;
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
return err;
}
static struct proto llcp_sock_proto = {
.name = "NFC_LLCP",
.owner = THIS_MODULE,
.obj_size = sizeof(struct nfc_llcp_sock),
};
static int llcp_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
{
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
struct nfc_llcp_local *local;
struct nfc_dev *dev;
struct sockaddr_nfc_llcp llcp_addr;
int len, ret = 0;
if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
addr->sa_family != AF_NFC)
return -EINVAL;
pr_debug("sk %p addr %p family %d\n", sk, addr, addr->sa_family);
memset(&llcp_addr, 0, sizeof(llcp_addr));
len = min_t(unsigned int, sizeof(llcp_addr), alen);
memcpy(&llcp_addr, addr, len);
/* This is going to be a listening socket, dsap must be 0 */
if (llcp_addr.dsap != 0)
return -EINVAL;
lock_sock(sk);
if (sk->sk_state != LLCP_CLOSED) {
ret = -EBADFD;
goto error;
}
dev = nfc_get_device(llcp_addr.dev_idx);
if (dev == NULL) {
ret = -ENODEV;
goto error;
}
local = nfc_llcp_find_local(dev);
if (local == NULL) {
ret = -ENODEV;
goto put_dev;
}
llcp_sock->dev = dev;
llcp_sock->local = nfc_llcp_local_get(local);
llcp_sock->nfc_protocol = llcp_addr.nfc_protocol;
llcp_sock->service_name_len = min_t(unsigned int,
llcp_addr.service_name_len,
NFC_LLCP_MAX_SERVICE_NAME);
llcp_sock->service_name = kmemdup(llcp_addr.service_name,
llcp_sock->service_name_len,
GFP_KERNEL);
if (!llcp_sock->service_name) {
nfc_llcp_local_put(llcp_sock->local);
llcp_sock->local = NULL;
ret = -ENOMEM;
goto put_dev;
}
llcp_sock->ssap = nfc_llcp_get_sdp_ssap(local, llcp_sock);
if (llcp_sock->ssap == LLCP_SAP_MAX) {
nfc_llcp_local_put(llcp_sock->local);
llcp_sock->local = NULL;
kfree(llcp_sock->service_name);
llcp_sock->service_name = NULL;
ret = -EADDRINUSE;
goto put_dev;
}
llcp_sock->reserved_ssap = llcp_sock->ssap;
nfc_llcp_sock_link(&local->sockets, sk);
pr_debug("Socket bound to SAP %d\n", llcp_sock->ssap);
sk->sk_state = LLCP_BOUND;
put_dev:
nfc_put_device(dev);
error:
release_sock(sk);
return ret;
}
static int llcp_raw_sock_bind(struct socket *sock, struct sockaddr *addr,
int alen)
{
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
struct nfc_llcp_local *local;
struct nfc_dev *dev;
struct sockaddr_nfc_llcp llcp_addr;
int len, ret = 0;
if (!addr || alen < offsetofend(struct sockaddr, sa_family) ||
addr->sa_family != AF_NFC)
return -EINVAL;
pr_debug("sk %p addr %p family %d\n", sk, addr, addr->sa_family);
memset(&llcp_addr, 0, sizeof(llcp_addr));
len = min_t(unsigned int, sizeof(llcp_addr), alen);
memcpy(&llcp_addr, addr, len);
lock_sock(sk);
if (sk->sk_state != LLCP_CLOSED) {
ret = -EBADFD;
goto error;
}
dev = nfc_get_device(llcp_addr.dev_idx);
if (dev == NULL) {
ret = -ENODEV;
goto error;
}
local = nfc_llcp_find_local(dev);
if (local == NULL) {
ret = -ENODEV;
goto put_dev;
}
llcp_sock->dev = dev;
llcp_sock->local = nfc_llcp_local_get(local);
llcp_sock->nfc_protocol = llcp_addr.nfc_protocol;
nfc_llcp_sock_link(&local->raw_sockets, sk);
sk->sk_state = LLCP_BOUND;
put_dev:
nfc_put_device(dev);
error:
release_sock(sk);
return ret;
}
static int llcp_sock_listen(struct socket *sock, int backlog)
{
struct sock *sk = sock->sk;
int ret = 0;
pr_debug("sk %p backlog %d\n", sk, backlog);
lock_sock(sk);
if ((sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM) ||
sk->sk_state != LLCP_BOUND) {
ret = -EBADFD;
goto error;
}
sk->sk_max_ack_backlog = backlog;
sk->sk_ack_backlog = 0;
pr_debug("Socket listening\n");
sk->sk_state = LLCP_LISTEN;
error:
release_sock(sk);
return ret;
}
static int nfc_llcp_setsockopt(struct socket *sock, int level, int optname,
sockptr_t optval, unsigned int optlen)
{
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
u32 opt;
int err = 0;
pr_debug("%p optname %d\n", sk, optname);
if (level != SOL_NFC)
return -ENOPROTOOPT;
lock_sock(sk);
switch (optname) {
case NFC_LLCP_RW:
if (sk->sk_state == LLCP_CONNECTED ||
sk->sk_state == LLCP_BOUND ||
sk->sk_state == LLCP_LISTEN) {
err = -EINVAL;
break;
}
if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
err = -EFAULT;
break;
}
if (opt > LLCP_MAX_RW) {
err = -EINVAL;
break;
}
llcp_sock->rw = (u8) opt;
break;
case NFC_LLCP_MIUX:
if (sk->sk_state == LLCP_CONNECTED ||
sk->sk_state == LLCP_BOUND ||
sk->sk_state == LLCP_LISTEN) {
err = -EINVAL;
break;
}
if (copy_from_sockptr(&opt, optval, sizeof(u32))) {
err = -EFAULT;
break;
}
if (opt > LLCP_MAX_MIUX) {
err = -EINVAL;
break;
}
llcp_sock->miux = cpu_to_be16((u16) opt);
break;
default:
err = -ENOPROTOOPT;
break;
}
release_sock(sk);
pr_debug("%p rw %d miux %d\n", llcp_sock,
llcp_sock->rw, llcp_sock->miux);
return err;
}
static int nfc_llcp_getsockopt(struct socket *sock, int level, int optname,
char __user *optval, int __user *optlen)
{
struct nfc_llcp_local *local;
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
int len, err = 0;
u16 miux, remote_miu;
u8 rw;
pr_debug("%p optname %d\n", sk, optname);
if (level != SOL_NFC)
return -ENOPROTOOPT;
if (get_user(len, optlen))
return -EFAULT;
local = llcp_sock->local;
if (!local)
return -ENODEV;
len = min_t(u32, len, sizeof(u32));
lock_sock(sk);
switch (optname) {
case NFC_LLCP_RW:
rw = llcp_sock->rw > LLCP_MAX_RW ? local->rw : llcp_sock->rw;
if (put_user(rw, (u32 __user *) optval))
err = -EFAULT;
break;
case NFC_LLCP_MIUX:
miux = be16_to_cpu(llcp_sock->miux) > LLCP_MAX_MIUX ?
be16_to_cpu(local->miux) : be16_to_cpu(llcp_sock->miux);
if (put_user(miux, (u32 __user *) optval))
err = -EFAULT;
break;
case NFC_LLCP_REMOTE_MIU:
remote_miu = llcp_sock->remote_miu > LLCP_MAX_MIU ?
local->remote_miu : llcp_sock->remote_miu;
if (put_user(remote_miu, (u32 __user *) optval))
err = -EFAULT;
break;
case NFC_LLCP_REMOTE_LTO:
if (put_user(local->remote_lto / 10, (u32 __user *) optval))
err = -EFAULT;
break;
case NFC_LLCP_REMOTE_RW:
if (put_user(llcp_sock->remote_rw, (u32 __user *) optval))
err = -EFAULT;
break;
default:
err = -ENOPROTOOPT;
break;
}
release_sock(sk);
if (put_user(len, optlen))
return -EFAULT;
return err;
}
void nfc_llcp_accept_unlink(struct sock *sk)
{
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
pr_debug("state %d\n", sk->sk_state);
list_del_init(&llcp_sock->accept_queue);
sk_acceptq_removed(llcp_sock->parent);
llcp_sock->parent = NULL;
sock_put(sk);
}
void nfc_llcp_accept_enqueue(struct sock *parent, struct sock *sk)
{
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
struct nfc_llcp_sock *llcp_sock_parent = nfc_llcp_sock(parent);
/* Lock will be free from unlink */
sock_hold(sk);
list_add_tail(&llcp_sock->accept_queue,
&llcp_sock_parent->accept_queue);
llcp_sock->parent = parent;
sk_acceptq_added(parent);
}
struct sock *nfc_llcp_accept_dequeue(struct sock *parent,
struct socket *newsock)
{
struct nfc_llcp_sock *lsk, *n, *llcp_parent;
struct sock *sk;
llcp_parent = nfc_llcp_sock(parent);
list_for_each_entry_safe(lsk, n, &llcp_parent->accept_queue,
accept_queue) {
sk = &lsk->sk;
lock_sock(sk);
if (sk->sk_state == LLCP_CLOSED) {
release_sock(sk);
nfc_llcp_accept_unlink(sk);
continue;
}
if (sk->sk_state == LLCP_CONNECTED || !newsock) {
list_del_init(&lsk->accept_queue);
sock_put(sk);
if (newsock)
sock_graft(sk, newsock);
release_sock(sk);
pr_debug("Returning sk state %d\n", sk->sk_state);
sk_acceptq_removed(parent);
return sk;
}
release_sock(sk);
}
return NULL;
}
static int llcp_sock_accept(struct socket *sock, struct socket *newsock,
int flags, bool kern)
{
DECLARE_WAITQUEUE(wait, current);
struct sock *sk = sock->sk, *new_sk;
long timeo;
int ret = 0;
pr_debug("parent %p\n", sk);
lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
if (sk->sk_state != LLCP_LISTEN) {
ret = -EBADFD;
goto error;
}
timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
/* Wait for an incoming connection. */
add_wait_queue_exclusive(sk_sleep(sk), &wait);
while (!(new_sk = nfc_llcp_accept_dequeue(sk, newsock))) {
set_current_state(TASK_INTERRUPTIBLE);
if (!timeo) {
ret = -EAGAIN;
break;
}
if (signal_pending(current)) {
ret = sock_intr_errno(timeo);
break;
}
release_sock(sk);
timeo = schedule_timeout(timeo);
lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
if (ret)
goto error;
newsock->state = SS_CONNECTED;
pr_debug("new socket %p\n", new_sk);
error:
release_sock(sk);
return ret;
}
static int llcp_sock_getname(struct socket *sock, struct sockaddr *uaddr,
int peer)
{
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, llcp_addr, uaddr);
if (llcp_sock == NULL || llcp_sock->dev == NULL)
return -EBADFD;
pr_debug("%p %d %d %d\n", sk, llcp_sock->target_idx,
llcp_sock->dsap, llcp_sock->ssap);
memset(llcp_addr, 0, sizeof(*llcp_addr));
lock_sock(sk);
if (!llcp_sock->dev) {
release_sock(sk);
return -EBADFD;
}
llcp_addr->sa_family = AF_NFC;
llcp_addr->dev_idx = llcp_sock->dev->idx;
llcp_addr->target_idx = llcp_sock->target_idx;
llcp_addr->nfc_protocol = llcp_sock->nfc_protocol;
llcp_addr->dsap = llcp_sock->dsap;
llcp_addr->ssap = llcp_sock->ssap;
llcp_addr->service_name_len = llcp_sock->service_name_len;
memcpy(llcp_addr->service_name, llcp_sock->service_name,
llcp_addr->service_name_len);
release_sock(sk);
return sizeof(struct sockaddr_nfc_llcp);
}
static inline __poll_t llcp_accept_poll(struct sock *parent)
{
struct nfc_llcp_sock *llcp_sock, *parent_sock;
struct sock *sk;
parent_sock = nfc_llcp_sock(parent);
list_for_each_entry(llcp_sock, &parent_sock->accept_queue,
accept_queue) {
sk = &llcp_sock->sk;
if (sk->sk_state == LLCP_CONNECTED)
return EPOLLIN | EPOLLRDNORM;
}
return 0;
}
static __poll_t llcp_sock_poll(struct file *file, struct socket *sock,
poll_table *wait)
{
struct sock *sk = sock->sk;
__poll_t mask = 0;
pr_debug("%p\n", sk);
sock_poll_wait(file, sock, wait);
if (sk->sk_state == LLCP_LISTEN)
return llcp_accept_poll(sk);
if (sk->sk_err || !skb_queue_empty_lockless(&sk->sk_error_queue))
mask |= EPOLLERR |
(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
mask |= EPOLLIN | EPOLLRDNORM;
if (sk->sk_state == LLCP_CLOSED)
mask |= EPOLLHUP;
if (sk->sk_shutdown & RCV_SHUTDOWN)
mask |= EPOLLRDHUP | EPOLLIN | EPOLLRDNORM;
if (sk->sk_shutdown == SHUTDOWN_MASK)
mask |= EPOLLHUP;
if (sock_writeable(sk) && sk->sk_state == LLCP_CONNECTED)
mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
else
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
pr_debug("mask 0x%x\n", mask);
return mask;
}
static int llcp_sock_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct nfc_llcp_local *local;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
int err = 0;
if (!sk)
return 0;
pr_debug("%p\n", sk);
local = llcp_sock->local;
if (local == NULL) {
err = -ENODEV;
goto out;
}
lock_sock(sk);
/* Send a DISC */
if (sk->sk_state == LLCP_CONNECTED)
nfc_llcp_send_disconnect(llcp_sock);
if (sk->sk_state == LLCP_LISTEN) {
struct nfc_llcp_sock *lsk, *n;
struct sock *accept_sk;
list_for_each_entry_safe(lsk, n, &llcp_sock->accept_queue,
accept_queue) {
accept_sk = &lsk->sk;
lock_sock(accept_sk);
nfc_llcp_send_disconnect(lsk);
nfc_llcp_accept_unlink(accept_sk);
release_sock(accept_sk);
}
}
if (llcp_sock->reserved_ssap < LLCP_SAP_MAX)
nfc_llcp_put_ssap(llcp_sock->local, llcp_sock->ssap);
release_sock(sk);
/* Keep this sock alive and therefore do not remove it from the sockets
* list until the DISC PDU has been actually sent. Otherwise we would
* reply with DM PDUs before sending the DISC one.
*/
if (sk->sk_state == LLCP_DISCONNECTING)
return err;
if (sock->type == SOCK_RAW)
nfc_llcp_sock_unlink(&local->raw_sockets, sk);
else
nfc_llcp_sock_unlink(&local->sockets, sk);
out:
sock_orphan(sk);
sock_put(sk);
return err;
}
static int llcp_sock_connect(struct socket *sock, struct sockaddr *_addr,
int len, int flags)
{
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
struct sockaddr_nfc_llcp *addr = (struct sockaddr_nfc_llcp *)_addr;
struct nfc_dev *dev;
struct nfc_llcp_local *local;
int ret = 0;
pr_debug("sock %p sk %p flags 0x%x\n", sock, sk, flags);
if (!addr || len < sizeof(*addr) || addr->sa_family != AF_NFC)
return -EINVAL;
if (addr->service_name_len == 0 && addr->dsap == 0)
return -EINVAL;
pr_debug("addr dev_idx=%u target_idx=%u protocol=%u\n", addr->dev_idx,
addr->target_idx, addr->nfc_protocol);
lock_sock(sk);
if (sk->sk_state == LLCP_CONNECTED) {
ret = -EISCONN;
goto error;
}
if (sk->sk_state == LLCP_CONNECTING) {
ret = -EINPROGRESS;
goto error;
}
dev = nfc_get_device(addr->dev_idx);
if (dev == NULL) {
ret = -ENODEV;
goto error;
}
local = nfc_llcp_find_local(dev);
if (local == NULL) {
ret = -ENODEV;
goto put_dev;
}
device_lock(&dev->dev);
if (dev->dep_link_up == false) {
ret = -ENOLINK;
device_unlock(&dev->dev);
goto put_dev;
}
device_unlock(&dev->dev);
if (local->rf_mode == NFC_RF_INITIATOR &&
addr->target_idx != local->target_idx) {
ret = -ENOLINK;
goto put_dev;
}
llcp_sock->dev = dev;
llcp_sock->local = nfc_llcp_local_get(local);
llcp_sock->ssap = nfc_llcp_get_local_ssap(local);
if (llcp_sock->ssap == LLCP_SAP_MAX) {
nfc_llcp_local_put(llcp_sock->local);
llcp_sock->local = NULL;
ret = -ENOMEM;
goto put_dev;
}
llcp_sock->reserved_ssap = llcp_sock->ssap;
if (addr->service_name_len == 0)
llcp_sock->dsap = addr->dsap;
else
llcp_sock->dsap = LLCP_SAP_SDP;
llcp_sock->nfc_protocol = addr->nfc_protocol;
llcp_sock->service_name_len = min_t(unsigned int,
addr->service_name_len,
NFC_LLCP_MAX_SERVICE_NAME);
llcp_sock->service_name = kmemdup(addr->service_name,
llcp_sock->service_name_len,
GFP_KERNEL);
if (!llcp_sock->service_name) {
ret = -ENOMEM;
goto sock_llcp_release;
}
nfc_llcp_sock_link(&local->connecting_sockets, sk);
ret = nfc_llcp_send_connect(llcp_sock);
if (ret)
goto sock_unlink;
sk->sk_state = LLCP_CONNECTING;
ret = sock_wait_state(sk, LLCP_CONNECTED,
sock_sndtimeo(sk, flags & O_NONBLOCK));
if (ret && ret != -EINPROGRESS)
goto sock_unlink;
release_sock(sk);
return ret;
sock_unlink:
nfc_llcp_sock_unlink(&local->connecting_sockets, sk);
kfree(llcp_sock->service_name);
llcp_sock->service_name = NULL;
sock_llcp_release:
nfc_llcp_put_ssap(local, llcp_sock->ssap);
nfc_llcp_local_put(llcp_sock->local);
llcp_sock->local = NULL;
put_dev:
nfc_put_device(dev);
error:
release_sock(sk);
return ret;
}
static int llcp_sock_sendmsg(struct socket *sock, struct msghdr *msg,
size_t len)
{
struct sock *sk = sock->sk;
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
int ret;
pr_debug("sock %p sk %p", sock, sk);
ret = sock_error(sk);
if (ret)
return ret;
if (msg->msg_flags & MSG_OOB)
return -EOPNOTSUPP;
lock_sock(sk);
if (sk->sk_type == SOCK_DGRAM) {
DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, addr,
msg->msg_name);
if (msg->msg_namelen < sizeof(*addr)) {
release_sock(sk);
return -EINVAL;
}
release_sock(sk);
return nfc_llcp_send_ui_frame(llcp_sock, addr->dsap, addr->ssap,
msg, len);
}
if (sk->sk_state != LLCP_CONNECTED) {
release_sock(sk);
return -ENOTCONN;
}
release_sock(sk);
return nfc_llcp_send_i_frame(llcp_sock, msg, len);
}
static int llcp_sock_recvmsg(struct socket *sock, struct msghdr *msg,
size_t len, int flags)
{
int noblock = flags & MSG_DONTWAIT;
struct sock *sk = sock->sk;
unsigned int copied, rlen;
struct sk_buff *skb, *cskb;
int err = 0;
pr_debug("%p %zu\n", sk, len);
lock_sock(sk);
if (sk->sk_state == LLCP_CLOSED &&
skb_queue_empty(&sk->sk_receive_queue)) {
release_sock(sk);
return 0;
}
release_sock(sk);
if (flags & (MSG_OOB))
return -EOPNOTSUPP;
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb) {
pr_err("Recv datagram failed state %d %d %d",
sk->sk_state, err, sock_error(sk));
if (sk->sk_shutdown & RCV_SHUTDOWN)
return 0;
return err;
}
rlen = skb->len; /* real length of skb */
copied = min_t(unsigned int, rlen, len);
cskb = skb;
if (skb_copy_datagram_msg(cskb, 0, msg, copied)) {
if (!(flags & MSG_PEEK))
skb_queue_head(&sk->sk_receive_queue, skb);
return -EFAULT;
}
sock_recv_timestamp(msg, sk, skb);
if (sk->sk_type == SOCK_DGRAM && msg->msg_name) {
struct nfc_llcp_ui_cb *ui_cb = nfc_llcp_ui_skb_cb(skb);
DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, sockaddr,
msg->msg_name);
msg->msg_namelen = sizeof(struct sockaddr_nfc_llcp);
pr_debug("Datagram socket %d %d\n", ui_cb->dsap, ui_cb->ssap);
memset(sockaddr, 0, sizeof(*sockaddr));
sockaddr->sa_family = AF_NFC;
sockaddr->nfc_protocol = NFC_PROTO_NFC_DEP;
sockaddr->dsap = ui_cb->dsap;
sockaddr->ssap = ui_cb->ssap;
}
/* Mark read part of skb as used */
if (!(flags & MSG_PEEK)) {
/* SOCK_STREAM: re-queue skb if it contains unreceived data */
if (sk->sk_type == SOCK_STREAM ||
sk->sk_type == SOCK_DGRAM ||
sk->sk_type == SOCK_RAW) {
skb_pull(skb, copied);
if (skb->len) {
skb_queue_head(&sk->sk_receive_queue, skb);
goto done;
}
}
kfree_skb(skb);
}
/* XXX Queue backlogged skbs */
done:
/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
copied = rlen;
return copied;
}
static const struct proto_ops llcp_sock_ops = {
.family = PF_NFC,
.owner = THIS_MODULE,
.bind = llcp_sock_bind,
.connect = llcp_sock_connect,
.release = llcp_sock_release,
.socketpair = sock_no_socketpair,
.accept = llcp_sock_accept,
.getname = llcp_sock_getname,
.poll = llcp_sock_poll,
.ioctl = sock_no_ioctl,
.listen = llcp_sock_listen,
.shutdown = sock_no_shutdown,
.setsockopt = nfc_llcp_setsockopt,
.getsockopt = nfc_llcp_getsockopt,
.sendmsg = llcp_sock_sendmsg,
.recvmsg = llcp_sock_recvmsg,
.mmap = sock_no_mmap,
};
static const struct proto_ops llcp_rawsock_ops = {
.family = PF_NFC,
.owner = THIS_MODULE,
.bind = llcp_raw_sock_bind,
.connect = sock_no_connect,
.release = llcp_sock_release,
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = llcp_sock_getname,
.poll = llcp_sock_poll,
.ioctl = sock_no_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
.sendmsg = sock_no_sendmsg,
.recvmsg = llcp_sock_recvmsg,
.mmap = sock_no_mmap,
};
static void llcp_sock_destruct(struct sock *sk)
{
struct nfc_llcp_sock *llcp_sock = nfc_llcp_sock(sk);
pr_debug("%p\n", sk);
if (sk->sk_state == LLCP_CONNECTED)
nfc_put_device(llcp_sock->dev);
skb_queue_purge(&sk->sk_receive_queue);
nfc_llcp_sock_free(llcp_sock);
if (!sock_flag(sk, SOCK_DEAD)) {
pr_err("Freeing alive NFC LLCP socket %p\n", sk);
return;
}
}
struct sock *nfc_llcp_sock_alloc(struct socket *sock, int type, gfp_t gfp, int kern)
{
struct sock *sk;
struct nfc_llcp_sock *llcp_sock;
sk = sk_alloc(&init_net, PF_NFC, gfp, &llcp_sock_proto, kern);
if (!sk)
return NULL;
llcp_sock = nfc_llcp_sock(sk);
sock_init_data(sock, sk);
sk->sk_state = LLCP_CLOSED;
sk->sk_protocol = NFC_SOCKPROTO_LLCP;
sk->sk_type = type;
sk->sk_destruct = llcp_sock_destruct;
llcp_sock->ssap = 0;
llcp_sock->dsap = LLCP_SAP_SDP;
llcp_sock->rw = LLCP_MAX_RW + 1;
llcp_sock->miux = cpu_to_be16(LLCP_MAX_MIUX + 1);
llcp_sock->send_n = llcp_sock->send_ack_n = 0;
llcp_sock->recv_n = llcp_sock->recv_ack_n = 0;
llcp_sock->remote_ready = 1;
llcp_sock->reserved_ssap = LLCP_SAP_MAX;
nfc_llcp_socket_remote_param_init(llcp_sock);
skb_queue_head_init(&llcp_sock->tx_queue);
skb_queue_head_init(&llcp_sock->tx_pending_queue);
INIT_LIST_HEAD(&llcp_sock->accept_queue);
if (sock != NULL)
sock->state = SS_UNCONNECTED;
return sk;
}
void nfc_llcp_sock_free(struct nfc_llcp_sock *sock)
{
kfree(sock->service_name);
skb_queue_purge(&sock->tx_queue);
skb_queue_purge(&sock->tx_pending_queue);
list_del_init(&sock->accept_queue);
sock->parent = NULL;
nfc_llcp_local_put(sock->local);
}
static int llcp_sock_create(struct net *net, struct socket *sock,
const struct nfc_protocol *nfc_proto, int kern)
{
struct sock *sk;
pr_debug("%p\n", sock);
if (sock->type != SOCK_STREAM &&
sock->type != SOCK_DGRAM &&
sock->type != SOCK_RAW)
return -ESOCKTNOSUPPORT;
if (sock->type == SOCK_RAW) {
if (!capable(CAP_NET_RAW))
return -EPERM;
sock->ops = &llcp_rawsock_ops;
} else {
sock->ops = &llcp_sock_ops;
}
sk = nfc_llcp_sock_alloc(sock, sock->type, GFP_ATOMIC, kern);
if (sk == NULL)
return -ENOMEM;
return 0;
}
static const struct nfc_protocol llcp_nfc_proto = {
.id = NFC_SOCKPROTO_LLCP,
.proto = &llcp_sock_proto,
.owner = THIS_MODULE,
.create = llcp_sock_create
};
int __init nfc_llcp_sock_init(void)
{
return nfc_proto_register(&llcp_nfc_proto);
}
void nfc_llcp_sock_exit(void)
{
nfc_proto_unregister(&llcp_nfc_proto);
}