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-rw-r--r--net/can/isotp.c141
1 files changed, 105 insertions, 36 deletions
diff --git a/net/can/isotp.c b/net/can/isotp.c
index 9bc344851704..84f9aba02901 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -85,10 +85,21 @@ MODULE_ALIAS("can-proto-6");
/* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can
* take full 32 bit values (4 Gbyte). We would need some good concept to handle
- * this between user space and kernel space. For now increase the static buffer
- * to something about 64 kbyte to be able to test this new functionality.
+ * this between user space and kernel space. For now set the static buffer to
+ * something about 8 kbyte to be able to test this new functionality.
*/
-#define MAX_MSG_LENGTH 66000
+#define DEFAULT_MAX_PDU_SIZE 8300
+
+/* maximum PDU size before ISO 15765-2:2016 extension was 4095 */
+#define MAX_12BIT_PDU_SIZE 4095
+
+/* limit the isotp pdu size from the optional module parameter to 1MByte */
+#define MAX_PDU_SIZE (1025 * 1024U)
+
+static unsigned int max_pdu_size __read_mostly = DEFAULT_MAX_PDU_SIZE;
+module_param(max_pdu_size, uint, 0444);
+MODULE_PARM_DESC(max_pdu_size, "maximum isotp pdu size (default "
+ __stringify(DEFAULT_MAX_PDU_SIZE) ")");
/* N_PCI type values in bits 7-4 of N_PCI bytes */
#define N_PCI_SF 0x00 /* single frame */
@@ -119,17 +130,20 @@ enum {
ISOTP_WAIT_FIRST_FC,
ISOTP_WAIT_FC,
ISOTP_WAIT_DATA,
- ISOTP_SENDING
+ ISOTP_SENDING,
+ ISOTP_SHUTDOWN,
};
struct tpcon {
- unsigned int idx;
+ u8 *buf;
+ unsigned int buflen;
unsigned int len;
+ unsigned int idx;
u32 state;
u8 bs;
u8 sn;
u8 ll_dl;
- u8 buf[MAX_MSG_LENGTH + 1];
+ u8 sbuf[DEFAULT_MAX_PDU_SIZE];
};
struct isotp_sock {
@@ -503,7 +517,17 @@ static int isotp_rcv_ff(struct sock *sk, struct canfd_frame *cf, int ae)
if (so->rx.len + ae + off + ff_pci_sz < so->rx.ll_dl)
return 1;
- if (so->rx.len > MAX_MSG_LENGTH) {
+ /* PDU size > default => try max_pdu_size */
+ if (so->rx.len > so->rx.buflen && so->rx.buflen < max_pdu_size) {
+ u8 *newbuf = kmalloc(max_pdu_size, GFP_ATOMIC);
+
+ if (newbuf) {
+ so->rx.buf = newbuf;
+ so->rx.buflen = max_pdu_size;
+ }
+ }
+
+ if (so->rx.len > so->rx.buflen) {
/* send FC frame with overflow status */
isotp_send_fc(sk, ae, ISOTP_FC_OVFLW);
return 1;
@@ -807,7 +831,7 @@ static void isotp_create_fframe(struct canfd_frame *cf, struct isotp_sock *so,
cf->data[0] = so->opt.ext_address;
/* create N_PCI bytes with 12/32 bit FF_DL data length */
- if (so->tx.len > 4095) {
+ if (so->tx.len > MAX_12BIT_PDU_SIZE) {
/* use 32 bit FF_DL notation */
cf->data[ae] = N_PCI_FF;
cf->data[ae + 1] = 0;
@@ -880,8 +904,8 @@ static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer)
txtimer);
struct sock *sk = &so->sk;
- /* don't handle timeouts in IDLE state */
- if (so->tx.state == ISOTP_IDLE)
+ /* don't handle timeouts in IDLE or SHUTDOWN state */
+ if (so->tx.state == ISOTP_IDLE || so->tx.state == ISOTP_SHUTDOWN)
return HRTIMER_NORESTART;
/* we did not get any flow control or echo frame in time */
@@ -918,7 +942,6 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
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;
@@ -928,26 +951,37 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
int off;
int err;
- if (!so->bound)
+ if (!so->bound || so->tx.state == ISOTP_SHUTDOWN)
return -EADDRNOTAVAIL;
+wait_free_buffer:
/* we do not support multiple buffers - for now */
- 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;
- }
+ if (wq_has_sleeper(&so->wait) && (msg->msg_flags & MSG_DONTWAIT))
+ return -EAGAIN;
- /* wait for complete transmission of current pdu */
- err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
- if (err)
- goto err_out;
+ /* wait for complete transmission of current pdu */
+ err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+ if (err)
+ goto err_event_drop;
- so->tx.state = ISOTP_SENDING;
+ if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) {
+ if (so->tx.state == ISOTP_SHUTDOWN)
+ return -EADDRNOTAVAIL;
+
+ goto wait_free_buffer;
+ }
+
+ /* PDU size > default => try max_pdu_size */
+ if (size > so->tx.buflen && so->tx.buflen < max_pdu_size) {
+ u8 *newbuf = kmalloc(max_pdu_size, GFP_KERNEL);
+
+ if (newbuf) {
+ so->tx.buf = newbuf;
+ so->tx.buflen = max_pdu_size;
+ }
}
- if (!size || size > MAX_MSG_LENGTH) {
+ if (!size || size > so->tx.buflen) {
err = -EINVAL;
goto err_out_drop;
}
@@ -1074,7 +1108,9 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
if (wait_tx_done) {
/* 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_event_drop;
if (sk->sk_err)
return -sk->sk_err;
@@ -1082,13 +1118,15 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
return size;
+err_event_drop:
+ /* got signal: force tx state machine to be idle */
+ so->tx.state = ISOTP_IDLE;
+ hrtimer_cancel(&so->txfrtimer);
+ hrtimer_cancel(&so->txtimer);
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);
+ so->tx.state = ISOTP_IDLE;
+ wake_up_interruptible(&so->wait);
return err;
}
@@ -1101,7 +1139,7 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
struct isotp_sock *so = isotp_sk(sk);
int ret = 0;
- if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK))
+ if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK | MSG_CMSG_COMPAT))
return -EINVAL;
if (!so->bound)
@@ -1120,7 +1158,7 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
if (ret < 0)
goto out_err;
- sock_recv_timestamp(msg, sk, skb);
+ sock_recv_cmsgs(msg, sk, skb);
if (msg->msg_name) {
__sockaddr_check_size(ISOTP_MIN_NAMELEN);
@@ -1150,10 +1188,12 @@ static int isotp_release(struct socket *sock)
net = sock_net(sk);
/* wait for complete transmission of current pdu */
- wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+ while (wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE) == 0 &&
+ cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SHUTDOWN) != ISOTP_IDLE)
+ ;
/* force state machines to be idle also when a signal occurred */
- so->tx.state = ISOTP_IDLE;
+ so->tx.state = ISOTP_SHUTDOWN;
so->rx.state = ISOTP_IDLE;
spin_lock(&isotp_notifier_lock);
@@ -1195,6 +1235,12 @@ static int isotp_release(struct socket *sock)
so->ifindex = 0;
so->bound = 0;
+ if (so->rx.buf != so->rx.sbuf)
+ kfree(so->rx.buf);
+
+ if (so->tx.buf != so->tx.sbuf)
+ kfree(so->tx.buf);
+
sock_orphan(sk);
sock->sk = NULL;
@@ -1591,6 +1637,11 @@ static int isotp_init(struct sock *sk)
so->rx.state = ISOTP_IDLE;
so->tx.state = ISOTP_IDLE;
+ so->rx.buf = so->rx.sbuf;
+ so->tx.buf = so->tx.sbuf;
+ so->rx.buflen = ARRAY_SIZE(so->rx.sbuf);
+ so->tx.buflen = ARRAY_SIZE(so->tx.sbuf);
+
hrtimer_init(&so->rxtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
so->rxtimer.function = isotp_rx_timer_handler;
hrtimer_init(&so->txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
@@ -1608,6 +1659,21 @@ static int isotp_init(struct sock *sk)
return 0;
}
+static __poll_t isotp_poll(struct file *file, struct socket *sock, poll_table *wait)
+{
+ struct sock *sk = sock->sk;
+ struct isotp_sock *so = isotp_sk(sk);
+
+ __poll_t mask = datagram_poll(file, sock, wait);
+ poll_wait(file, &so->wait, wait);
+
+ /* Check for false positives due to TX state */
+ if ((mask & EPOLLWRNORM) && (so->tx.state != ISOTP_IDLE))
+ mask &= ~(EPOLLOUT | EPOLLWRNORM);
+
+ return mask;
+}
+
static int isotp_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
unsigned long arg)
{
@@ -1623,7 +1689,7 @@ static const struct proto_ops isotp_ops = {
.socketpair = sock_no_socketpair,
.accept = sock_no_accept,
.getname = isotp_getname,
- .poll = datagram_poll,
+ .poll = isotp_poll,
.ioctl = isotp_sock_no_ioctlcmd,
.gettstamp = sock_gettstamp,
.listen = sock_no_listen,
@@ -1658,7 +1724,10 @@ static __init int isotp_module_init(void)
{
int err;
- pr_info("can: isotp protocol\n");
+ max_pdu_size = max_t(unsigned int, max_pdu_size, MAX_12BIT_PDU_SIZE);
+ max_pdu_size = min_t(unsigned int, max_pdu_size, MAX_PDU_SIZE);
+
+ pr_info("can: isotp protocol (max_pdu_size %d)\n", max_pdu_size);
err = can_proto_register(&isotp_can_proto);
if (err < 0)