#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
+#include <linux/spinlock.h>
#include <linux/hrtimer.h>
#include <linux/wait.h>
#include <linux/uio.h>
};
struct tpcon {
- int idx;
- int len;
- u8 state;
+ unsigned int idx;
+ unsigned int len;
+ u32 state;
u8 bs;
u8 sn;
u8 ll_dl;
struct can_isotp_options opt;
struct can_isotp_fc_options rxfc, txfc;
struct can_isotp_ll_options ll;
+ u32 frame_txtime;
u32 force_tx_stmin;
u32 force_rx_stmin;
struct tpcon rx, tx;
struct list_head notifier;
wait_queue_head_t wait;
+ spinlock_t rx_lock; /* protect single thread state machine */
};
static LIST_HEAD(isotp_notifier_list);
so->tx_gap = ktime_set(0, 0);
/* add transmission time for CAN frame N_As */
- so->tx_gap = ktime_add_ns(so->tx_gap, so->opt.frame_txtime);
+ so->tx_gap = ktime_add_ns(so->tx_gap, so->frame_txtime);
/* add waiting time for consecutive frames N_Cs */
if (so->opt.flags & CAN_ISOTP_FORCE_TXSTMIN)
so->tx_gap = ktime_add_ns(so->tx_gap,
n_pci_type = cf->data[ae] & 0xF0;
+ /* Make sure the state changes and data structures stay consistent at
+ * CAN frame reception time. This locking is not needed in real world
+ * use cases but the inconsistency can be triggered with syzkaller.
+ */
+ spin_lock(&so->rx_lock);
+
if (so->opt.flags & CAN_ISOTP_HALF_DUPLEX) {
/* check rx/tx path half duplex expectations */
if ((so->tx.state != ISOTP_IDLE && n_pci_type != N_PCI_FC) ||
(so->rx.state != ISOTP_IDLE && n_pci_type == N_PCI_FC))
- return;
+ goto out_unlock;
}
switch (n_pci_type) {
isotp_rcv_cf(sk, cf, ae, skb);
break;
}
+
+out_unlock:
+ spin_unlock(&so->rx_lock);
}
static void isotp_fill_dataframe(struct canfd_frame *cf, struct isotp_sock *so,
{
struct sock *sk = sock->sk;
struct isotp_sock *so = isotp_sk(sk);
+ u32 old_state = so->tx.state;
struct sk_buff *skb;
struct net_device *dev;
struct canfd_frame *cf;
return -EADDRNOTAVAIL;
/* we do not support multiple buffers - for now */
- if (so->tx.state != ISOTP_IDLE || wq_has_sleeper(&so->wait)) {
- if (msg->msg_flags & MSG_DONTWAIT)
- return -EAGAIN;
+ if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE ||
+ wq_has_sleeper(&so->wait)) {
+ if (msg->msg_flags & MSG_DONTWAIT) {
+ err = -EAGAIN;
+ goto err_out;
+ }
/* wait for complete transmission of current pdu */
- wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+ err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+ if (err)
+ goto err_out;
}
- if (!size || size > MAX_MSG_LENGTH)
- return -EINVAL;
+ if (!size || size > MAX_MSG_LENGTH) {
+ err = -EINVAL;
+ goto err_out_drop;
+ }
/* take care of a potential SF_DL ESC offset for TX_DL > 8 */
off = (so->tx.ll_dl > CAN_MAX_DLEN) ? 1 : 0;
/* does the given data fit into a single frame for SF_BROADCAST? */
if ((so->opt.flags & CAN_ISOTP_SF_BROADCAST) &&
- (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off))
- return -EINVAL;
+ (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off)) {
+ err = -EINVAL;
+ goto err_out_drop;
+ }
err = memcpy_from_msg(so->tx.buf, msg, size);
if (err < 0)
- return err;
+ goto err_out_drop;
dev = dev_get_by_index(sock_net(sk), so->ifindex);
- if (!dev)
- return -ENXIO;
+ if (!dev) {
+ err = -ENXIO;
+ goto err_out_drop;
+ }
skb = sock_alloc_send_skb(sk, so->ll.mtu + sizeof(struct can_skb_priv),
msg->msg_flags & MSG_DONTWAIT, &err);
if (!skb) {
dev_put(dev);
- return err;
+ goto err_out_drop;
}
can_skb_reserve(skb);
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
- so->tx.state = ISOTP_SENDING;
so->tx.len = size;
so->tx.idx = 0;
if (err) {
pr_notice_once("can-isotp: %s: can_send_ret %pe\n",
__func__, ERR_PTR(err));
- return err;
+ goto err_out_drop;
}
if (wait_tx_done) {
/* wait for complete transmission of current pdu */
wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+
+ if (sk->sk_err)
+ return -sk->sk_err;
}
return size;
+
+err_out_drop:
+ /* drop this PDU and unlock a potential wait queue */
+ old_state = ISOTP_IDLE;
+err_out:
+ so->tx.state = old_state;
+ if (so->tx.state == ISOTP_IDLE)
+ wake_up_interruptible(&so->wait);
+
+ return err;
}
static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
{
struct sock *sk = sock->sk;
struct sk_buff *skb;
- int err = 0;
- int noblock;
+ struct isotp_sock *so = isotp_sk(sk);
+ int noblock = flags & MSG_DONTWAIT;
+ int ret = 0;
- noblock = flags & MSG_DONTWAIT;
- flags &= ~MSG_DONTWAIT;
+ if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK))
+ return -EINVAL;
+
+ if (!so->bound)
+ return -EADDRNOTAVAIL;
- skb = skb_recv_datagram(sk, flags, noblock, &err);
+ flags &= ~MSG_DONTWAIT;
+ skb = skb_recv_datagram(sk, flags, noblock, &ret);
if (!skb)
- return err;
+ return ret;
if (size < skb->len)
msg->msg_flags |= MSG_TRUNC;
else
size = skb->len;
- err = memcpy_to_msg(msg, skb->data, size);
- if (err < 0) {
- skb_free_datagram(sk, skb);
- return err;
- }
+ ret = memcpy_to_msg(msg, skb->data, size);
+ if (ret < 0)
+ goto out_err;
sock_recv_timestamp(msg, sk, skb);
memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
}
+ /* set length of return value */
+ ret = (flags & MSG_TRUNC) ? skb->len : size;
+
+out_err:
skb_free_datagram(sk, skb);
- return size;
+ return ret;
}
static int isotp_release(struct socket *sock)
struct net *net = sock_net(sk);
int ifindex;
struct net_device *dev;
+ canid_t tx_id, rx_id;
int err = 0;
int notify_enetdown = 0;
int do_rx_reg = 1;
if (len < ISOTP_MIN_NAMELEN)
return -EINVAL;
- if (addr->can_addr.tp.tx_id & (CAN_ERR_FLAG | CAN_RTR_FLAG))
- return -EADDRNOTAVAIL;
+ /* sanitize tx/rx CAN identifiers */
+ tx_id = addr->can_addr.tp.tx_id;
+ if (tx_id & CAN_EFF_FLAG)
+ tx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK);
+ else
+ tx_id &= CAN_SFF_MASK;
+
+ rx_id = addr->can_addr.tp.rx_id;
+ if (rx_id & CAN_EFF_FLAG)
+ rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK);
+ else
+ rx_id &= CAN_SFF_MASK;
if (!addr->can_ifindex)
return -ENODEV;
do_rx_reg = 0;
/* do not validate rx address for functional addressing */
- if (do_rx_reg) {
- if (addr->can_addr.tp.rx_id == addr->can_addr.tp.tx_id) {
- err = -EADDRNOTAVAIL;
- goto out;
- }
-
- if (addr->can_addr.tp.rx_id & (CAN_ERR_FLAG | CAN_RTR_FLAG)) {
- err = -EADDRNOTAVAIL;
- goto out;
- }
+ if (do_rx_reg && rx_id == tx_id) {
+ err = -EADDRNOTAVAIL;
+ goto out;
}
if (so->bound && addr->can_ifindex == so->ifindex &&
- addr->can_addr.tp.rx_id == so->rxid &&
- addr->can_addr.tp.tx_id == so->txid)
+ rx_id == so->rxid && tx_id == so->txid)
goto out;
dev = dev_get_by_index(net, addr->can_ifindex);
ifindex = dev->ifindex;
if (do_rx_reg)
- can_rx_register(net, dev, addr->can_addr.tp.rx_id,
- SINGLE_MASK(addr->can_addr.tp.rx_id),
+ can_rx_register(net, dev, rx_id, SINGLE_MASK(rx_id),
isotp_rcv, sk, "isotp", sk);
dev_put(dev);
/* switch to new settings */
so->ifindex = ifindex;
- so->rxid = addr->can_addr.tp.rx_id;
- so->txid = addr->can_addr.tp.tx_id;
+ so->rxid = rx_id;
+ so->txid = tx_id;
so->bound = 1;
out:
/* no separate rx_ext_address is given => use ext_address */
if (!(so->opt.flags & CAN_ISOTP_RX_EXT_ADDR))
so->opt.rx_ext_address = so->opt.ext_address;
+
+ /* check for frame_txtime changes (0 => no changes) */
+ if (so->opt.frame_txtime) {
+ if (so->opt.frame_txtime == CAN_ISOTP_FRAME_TXTIME_ZERO)
+ so->frame_txtime = 0;
+ else
+ so->frame_txtime = so->opt.frame_txtime;
+ }
break;
case CAN_ISOTP_RECV_FC:
so->opt.rxpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT;
so->opt.txpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT;
so->opt.frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME;
+ so->frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME;
so->rxfc.bs = CAN_ISOTP_DEFAULT_RECV_BS;
so->rxfc.stmin = CAN_ISOTP_DEFAULT_RECV_STMIN;
so->rxfc.wftmax = CAN_ISOTP_DEFAULT_RECV_WFTMAX;
so->txtimer.function = isotp_tx_timer_handler;
init_waitqueue_head(&so->wait);
+ spin_lock_init(&so->rx_lock);
spin_lock(&isotp_notifier_lock);
list_add_tail(&so->notifier, &isotp_notifier_list);
projects / platform / kernel / linux-rpi.git / blobdiff