v4.19.13 snapshot.
diff --git a/net/atm/svc.c b/net/atm/svc.c
new file mode 100644
index 0000000..2f91b76
--- /dev/null
+++ b/net/atm/svc.c
@@ -0,0 +1,691 @@
+// SPDX-License-Identifier: GPL-2.0
+/* net/atm/svc.c - ATM SVC sockets */
+
+/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
+
+#include <linux/string.h>
+#include <linux/net.h>		/* struct socket, struct proto_ops */
+#include <linux/errno.h>	/* error codes */
+#include <linux/kernel.h>	/* printk */
+#include <linux/skbuff.h>
+#include <linux/wait.h>
+#include <linux/sched/signal.h>
+#include <linux/fcntl.h>	/* O_NONBLOCK */
+#include <linux/init.h>
+#include <linux/atm.h>		/* ATM stuff */
+#include <linux/atmsap.h>
+#include <linux/atmsvc.h>
+#include <linux/atmdev.h>
+#include <linux/bitops.h>
+#include <net/sock.h>		/* for sock_no_* */
+#include <linux/uaccess.h>
+#include <linux/export.h>
+
+#include "resources.h"
+#include "common.h"		/* common for PVCs and SVCs */
+#include "signaling.h"
+#include "addr.h"
+
+static int svc_create(struct net *net, struct socket *sock, int protocol,
+		      int kern);
+
+/*
+ * Note: since all this is still nicely synchronized with the signaling demon,
+ *       there's no need to protect sleep loops with clis. If signaling is
+ *       moved into the kernel, that would change.
+ */
+
+
+static int svc_shutdown(struct socket *sock, int how)
+{
+	return 0;
+}
+
+static void svc_disconnect(struct atm_vcc *vcc)
+{
+	DEFINE_WAIT(wait);
+	struct sk_buff *skb;
+	struct sock *sk = sk_atm(vcc);
+
+	pr_debug("%p\n", vcc);
+	if (test_bit(ATM_VF_REGIS, &vcc->flags)) {
+		sigd_enq(vcc, as_close, NULL, NULL, NULL);
+		for (;;) {
+			prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
+			if (test_bit(ATM_VF_RELEASED, &vcc->flags) || !sigd)
+				break;
+			schedule();
+		}
+		finish_wait(sk_sleep(sk), &wait);
+	}
+	/* beware - socket is still in use by atmsigd until the last
+	   as_indicate has been answered */
+	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+		atm_return(vcc, skb->truesize);
+		pr_debug("LISTEN REL\n");
+		sigd_enq2(NULL, as_reject, vcc, NULL, NULL, &vcc->qos, 0);
+		dev_kfree_skb(skb);
+	}
+	clear_bit(ATM_VF_REGIS, &vcc->flags);
+	/* ... may retry later */
+}
+
+static int svc_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct atm_vcc *vcc;
+
+	if (sk) {
+		vcc = ATM_SD(sock);
+		pr_debug("%p\n", vcc);
+		clear_bit(ATM_VF_READY, &vcc->flags);
+		/*
+		 * VCC pointer is used as a reference,
+		 * so we must not free it (thereby subjecting it to re-use)
+		 * before all pending connections are closed
+		 */
+		svc_disconnect(vcc);
+		vcc_release(sock);
+	}
+	return 0;
+}
+
+static int svc_bind(struct socket *sock, struct sockaddr *sockaddr,
+		    int sockaddr_len)
+{
+	DEFINE_WAIT(wait);
+	struct sock *sk = sock->sk;
+	struct sockaddr_atmsvc *addr;
+	struct atm_vcc *vcc;
+	int error;
+
+	if (sockaddr_len != sizeof(struct sockaddr_atmsvc))
+		return -EINVAL;
+	lock_sock(sk);
+	if (sock->state == SS_CONNECTED) {
+		error = -EISCONN;
+		goto out;
+	}
+	if (sock->state != SS_UNCONNECTED) {
+		error = -EINVAL;
+		goto out;
+	}
+	vcc = ATM_SD(sock);
+	addr = (struct sockaddr_atmsvc *) sockaddr;
+	if (addr->sas_family != AF_ATMSVC) {
+		error = -EAFNOSUPPORT;
+		goto out;
+	}
+	clear_bit(ATM_VF_BOUND, &vcc->flags);
+	    /* failing rebind will kill old binding */
+	/* @@@ check memory (de)allocation on rebind */
+	if (!test_bit(ATM_VF_HASQOS, &vcc->flags)) {
+		error = -EBADFD;
+		goto out;
+	}
+	vcc->local = *addr;
+	set_bit(ATM_VF_WAITING, &vcc->flags);
+	sigd_enq(vcc, as_bind, NULL, NULL, &vcc->local);
+	for (;;) {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
+		if (!test_bit(ATM_VF_WAITING, &vcc->flags) || !sigd)
+			break;
+		schedule();
+	}
+	finish_wait(sk_sleep(sk), &wait);
+	clear_bit(ATM_VF_REGIS, &vcc->flags); /* doesn't count */
+	if (!sigd) {
+		error = -EUNATCH;
+		goto out;
+	}
+	if (!sk->sk_err)
+		set_bit(ATM_VF_BOUND, &vcc->flags);
+	error = -sk->sk_err;
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_connect(struct socket *sock, struct sockaddr *sockaddr,
+		       int sockaddr_len, int flags)
+{
+	DEFINE_WAIT(wait);
+	struct sock *sk = sock->sk;
+	struct sockaddr_atmsvc *addr;
+	struct atm_vcc *vcc = ATM_SD(sock);
+	int error;
+
+	pr_debug("%p\n", vcc);
+	lock_sock(sk);
+	if (sockaddr_len != sizeof(struct sockaddr_atmsvc)) {
+		error = -EINVAL;
+		goto out;
+	}
+
+	switch (sock->state) {
+	default:
+		error = -EINVAL;
+		goto out;
+	case SS_CONNECTED:
+		error = -EISCONN;
+		goto out;
+	case SS_CONNECTING:
+		if (test_bit(ATM_VF_WAITING, &vcc->flags)) {
+			error = -EALREADY;
+			goto out;
+		}
+		sock->state = SS_UNCONNECTED;
+		if (sk->sk_err) {
+			error = -sk->sk_err;
+			goto out;
+		}
+		break;
+	case SS_UNCONNECTED:
+		addr = (struct sockaddr_atmsvc *) sockaddr;
+		if (addr->sas_family != AF_ATMSVC) {
+			error = -EAFNOSUPPORT;
+			goto out;
+		}
+		if (!test_bit(ATM_VF_HASQOS, &vcc->flags)) {
+			error = -EBADFD;
+			goto out;
+		}
+		if (vcc->qos.txtp.traffic_class == ATM_ANYCLASS ||
+		    vcc->qos.rxtp.traffic_class == ATM_ANYCLASS) {
+			error = -EINVAL;
+			goto out;
+		}
+		if (!vcc->qos.txtp.traffic_class &&
+		    !vcc->qos.rxtp.traffic_class) {
+			error = -EINVAL;
+			goto out;
+		}
+		vcc->remote = *addr;
+		set_bit(ATM_VF_WAITING, &vcc->flags);
+		sigd_enq(vcc, as_connect, NULL, NULL, &vcc->remote);
+		if (flags & O_NONBLOCK) {
+			sock->state = SS_CONNECTING;
+			error = -EINPROGRESS;
+			goto out;
+		}
+		error = 0;
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		while (test_bit(ATM_VF_WAITING, &vcc->flags) && sigd) {
+			schedule();
+			if (!signal_pending(current)) {
+				prepare_to_wait(sk_sleep(sk), &wait,
+						TASK_INTERRUPTIBLE);
+				continue;
+			}
+			pr_debug("*ABORT*\n");
+			/*
+			 * This is tricky:
+			 *   Kernel ---close--> Demon
+			 *   Kernel <--close--- Demon
+			 * or
+			 *   Kernel ---close--> Demon
+			 *   Kernel <--error--- Demon
+			 * or
+			 *   Kernel ---close--> Demon
+			 *   Kernel <--okay---- Demon
+			 *   Kernel <--close--- Demon
+			 */
+			sigd_enq(vcc, as_close, NULL, NULL, NULL);
+			while (test_bit(ATM_VF_WAITING, &vcc->flags) && sigd) {
+				prepare_to_wait(sk_sleep(sk), &wait,
+						TASK_INTERRUPTIBLE);
+				schedule();
+			}
+			if (!sk->sk_err)
+				while (!test_bit(ATM_VF_RELEASED, &vcc->flags) &&
+				       sigd) {
+					prepare_to_wait(sk_sleep(sk), &wait,
+							TASK_INTERRUPTIBLE);
+					schedule();
+				}
+			clear_bit(ATM_VF_REGIS, &vcc->flags);
+			clear_bit(ATM_VF_RELEASED, &vcc->flags);
+			clear_bit(ATM_VF_CLOSE, &vcc->flags);
+			    /* we're gone now but may connect later */
+			error = -EINTR;
+			break;
+		}
+		finish_wait(sk_sleep(sk), &wait);
+		if (error)
+			goto out;
+		if (!sigd) {
+			error = -EUNATCH;
+			goto out;
+		}
+		if (sk->sk_err) {
+			error = -sk->sk_err;
+			goto out;
+		}
+	}
+
+	vcc->qos.txtp.max_pcr = SELECT_TOP_PCR(vcc->qos.txtp);
+	vcc->qos.txtp.pcr = 0;
+	vcc->qos.txtp.min_pcr = 0;
+
+	error = vcc_connect(sock, vcc->itf, vcc->vpi, vcc->vci);
+	if (!error)
+		sock->state = SS_CONNECTED;
+	else
+		(void)svc_disconnect(vcc);
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_listen(struct socket *sock, int backlog)
+{
+	DEFINE_WAIT(wait);
+	struct sock *sk = sock->sk;
+	struct atm_vcc *vcc = ATM_SD(sock);
+	int error;
+
+	pr_debug("%p\n", vcc);
+	lock_sock(sk);
+	/* let server handle listen on unbound sockets */
+	if (test_bit(ATM_VF_SESSION, &vcc->flags)) {
+		error = -EINVAL;
+		goto out;
+	}
+	if (test_bit(ATM_VF_LISTEN, &vcc->flags)) {
+		error = -EADDRINUSE;
+		goto out;
+	}
+	set_bit(ATM_VF_WAITING, &vcc->flags);
+	sigd_enq(vcc, as_listen, NULL, NULL, &vcc->local);
+	for (;;) {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
+		if (!test_bit(ATM_VF_WAITING, &vcc->flags) || !sigd)
+			break;
+		schedule();
+	}
+	finish_wait(sk_sleep(sk), &wait);
+	if (!sigd) {
+		error = -EUNATCH;
+		goto out;
+	}
+	set_bit(ATM_VF_LISTEN, &vcc->flags);
+	vcc_insert_socket(sk);
+	sk->sk_max_ack_backlog = backlog > 0 ? backlog : ATM_BACKLOG_DEFAULT;
+	error = -sk->sk_err;
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_accept(struct socket *sock, struct socket *newsock, int flags,
+		      bool kern)
+{
+	struct sock *sk = sock->sk;
+	struct sk_buff *skb;
+	struct atmsvc_msg *msg;
+	struct atm_vcc *old_vcc = ATM_SD(sock);
+	struct atm_vcc *new_vcc;
+	int error;
+
+	lock_sock(sk);
+
+	error = svc_create(sock_net(sk), newsock, 0, kern);
+	if (error)
+		goto out;
+
+	new_vcc = ATM_SD(newsock);
+
+	pr_debug("%p -> %p\n", old_vcc, new_vcc);
+	while (1) {
+		DEFINE_WAIT(wait);
+
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		while (!(skb = skb_dequeue(&sk->sk_receive_queue)) &&
+		       sigd) {
+			if (test_bit(ATM_VF_RELEASED, &old_vcc->flags))
+				break;
+			if (test_bit(ATM_VF_CLOSE, &old_vcc->flags)) {
+				error = -sk->sk_err;
+				break;
+			}
+			if (flags & O_NONBLOCK) {
+				error = -EAGAIN;
+				break;
+			}
+			release_sock(sk);
+			schedule();
+			lock_sock(sk);
+			if (signal_pending(current)) {
+				error = -ERESTARTSYS;
+				break;
+			}
+			prepare_to_wait(sk_sleep(sk), &wait,
+					TASK_INTERRUPTIBLE);
+		}
+		finish_wait(sk_sleep(sk), &wait);
+		if (error)
+			goto out;
+		if (!skb) {
+			error = -EUNATCH;
+			goto out;
+		}
+		msg = (struct atmsvc_msg *)skb->data;
+		new_vcc->qos = msg->qos;
+		set_bit(ATM_VF_HASQOS, &new_vcc->flags);
+		new_vcc->remote = msg->svc;
+		new_vcc->local = msg->local;
+		new_vcc->sap = msg->sap;
+		error = vcc_connect(newsock, msg->pvc.sap_addr.itf,
+				    msg->pvc.sap_addr.vpi,
+				    msg->pvc.sap_addr.vci);
+		dev_kfree_skb(skb);
+		sk->sk_ack_backlog--;
+		if (error) {
+			sigd_enq2(NULL, as_reject, old_vcc, NULL, NULL,
+				  &old_vcc->qos, error);
+			error = error == -EAGAIN ? -EBUSY : error;
+			goto out;
+		}
+		/* wait should be short, so we ignore the non-blocking flag */
+		set_bit(ATM_VF_WAITING, &new_vcc->flags);
+		sigd_enq(new_vcc, as_accept, old_vcc, NULL, NULL);
+		for (;;) {
+			prepare_to_wait(sk_sleep(sk_atm(new_vcc)), &wait,
+					TASK_UNINTERRUPTIBLE);
+			if (!test_bit(ATM_VF_WAITING, &new_vcc->flags) || !sigd)
+				break;
+			release_sock(sk);
+			schedule();
+			lock_sock(sk);
+		}
+		finish_wait(sk_sleep(sk_atm(new_vcc)), &wait);
+		if (!sigd) {
+			error = -EUNATCH;
+			goto out;
+		}
+		if (!sk_atm(new_vcc)->sk_err)
+			break;
+		if (sk_atm(new_vcc)->sk_err != ERESTARTSYS) {
+			error = -sk_atm(new_vcc)->sk_err;
+			goto out;
+		}
+	}
+	newsock->state = SS_CONNECTED;
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_getname(struct socket *sock, struct sockaddr *sockaddr,
+		       int peer)
+{
+	struct sockaddr_atmsvc *addr;
+
+	addr = (struct sockaddr_atmsvc *) sockaddr;
+	memcpy(addr, peer ? &ATM_SD(sock)->remote : &ATM_SD(sock)->local,
+	       sizeof(struct sockaddr_atmsvc));
+	return sizeof(struct sockaddr_atmsvc);
+}
+
+int svc_change_qos(struct atm_vcc *vcc, struct atm_qos *qos)
+{
+	struct sock *sk = sk_atm(vcc);
+	DEFINE_WAIT(wait);
+
+	set_bit(ATM_VF_WAITING, &vcc->flags);
+	sigd_enq2(vcc, as_modify, NULL, NULL, &vcc->local, qos, 0);
+	for (;;) {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_UNINTERRUPTIBLE);
+		if (!test_bit(ATM_VF_WAITING, &vcc->flags) ||
+		    test_bit(ATM_VF_RELEASED, &vcc->flags) || !sigd) {
+			break;
+		}
+		schedule();
+	}
+	finish_wait(sk_sleep(sk), &wait);
+	if (!sigd)
+		return -EUNATCH;
+	return -sk->sk_err;
+}
+
+static int svc_setsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, unsigned int optlen)
+{
+	struct sock *sk = sock->sk;
+	struct atm_vcc *vcc = ATM_SD(sock);
+	int value, error = 0;
+
+	lock_sock(sk);
+	switch (optname) {
+	case SO_ATMSAP:
+		if (level != SOL_ATM || optlen != sizeof(struct atm_sap)) {
+			error = -EINVAL;
+			goto out;
+		}
+		if (copy_from_user(&vcc->sap, optval, optlen)) {
+			error = -EFAULT;
+			goto out;
+		}
+		set_bit(ATM_VF_HASSAP, &vcc->flags);
+		break;
+	case SO_MULTIPOINT:
+		if (level != SOL_ATM || optlen != sizeof(int)) {
+			error = -EINVAL;
+			goto out;
+		}
+		if (get_user(value, (int __user *)optval)) {
+			error = -EFAULT;
+			goto out;
+		}
+		if (value == 1)
+			set_bit(ATM_VF_SESSION, &vcc->flags);
+		else if (value == 0)
+			clear_bit(ATM_VF_SESSION, &vcc->flags);
+		else
+			error = -EINVAL;
+		break;
+	default:
+		error = vcc_setsockopt(sock, level, optname, optval, optlen);
+	}
+
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_getsockopt(struct socket *sock, int level, int optname,
+			  char __user *optval, int __user *optlen)
+{
+	struct sock *sk = sock->sk;
+	int error = 0, len;
+
+	lock_sock(sk);
+	if (!__SO_LEVEL_MATCH(optname, level) || optname != SO_ATMSAP) {
+		error = vcc_getsockopt(sock, level, optname, optval, optlen);
+		goto out;
+	}
+	if (get_user(len, optlen)) {
+		error = -EFAULT;
+		goto out;
+	}
+	if (len != sizeof(struct atm_sap)) {
+		error = -EINVAL;
+		goto out;
+	}
+	if (copy_to_user(optval, &ATM_SD(sock)->sap, sizeof(struct atm_sap))) {
+		error = -EFAULT;
+		goto out;
+	}
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_addparty(struct socket *sock, struct sockaddr *sockaddr,
+			int sockaddr_len, int flags)
+{
+	DEFINE_WAIT(wait);
+	struct sock *sk = sock->sk;
+	struct atm_vcc *vcc = ATM_SD(sock);
+	int error;
+
+	lock_sock(sk);
+	set_bit(ATM_VF_WAITING, &vcc->flags);
+	sigd_enq(vcc, as_addparty, NULL, NULL,
+		 (struct sockaddr_atmsvc *) sockaddr);
+	if (flags & O_NONBLOCK) {
+		error = -EINPROGRESS;
+		goto out;
+	}
+	pr_debug("added wait queue\n");
+	for (;;) {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		if (!test_bit(ATM_VF_WAITING, &vcc->flags) || !sigd)
+			break;
+		schedule();
+	}
+	finish_wait(sk_sleep(sk), &wait);
+	error = -xchg(&sk->sk_err_soft, 0);
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_dropparty(struct socket *sock, int ep_ref)
+{
+	DEFINE_WAIT(wait);
+	struct sock *sk = sock->sk;
+	struct atm_vcc *vcc = ATM_SD(sock);
+	int error;
+
+	lock_sock(sk);
+	set_bit(ATM_VF_WAITING, &vcc->flags);
+	sigd_enq2(vcc, as_dropparty, NULL, NULL, NULL, NULL, ep_ref);
+	for (;;) {
+		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+		if (!test_bit(ATM_VF_WAITING, &vcc->flags) || !sigd)
+			break;
+		schedule();
+	}
+	finish_wait(sk_sleep(sk), &wait);
+	if (!sigd) {
+		error = -EUNATCH;
+		goto out;
+	}
+	error = -xchg(&sk->sk_err_soft, 0);
+out:
+	release_sock(sk);
+	return error;
+}
+
+static int svc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	int error, ep_ref;
+	struct sockaddr_atmsvc sa;
+	struct atm_vcc *vcc = ATM_SD(sock);
+
+	switch (cmd) {
+	case ATM_ADDPARTY:
+		if (!test_bit(ATM_VF_SESSION, &vcc->flags))
+			return -EINVAL;
+		if (copy_from_user(&sa, (void __user *) arg, sizeof(sa)))
+			return -EFAULT;
+		error = svc_addparty(sock, (struct sockaddr *)&sa, sizeof(sa),
+				     0);
+		break;
+	case ATM_DROPPARTY:
+		if (!test_bit(ATM_VF_SESSION, &vcc->flags))
+			return -EINVAL;
+		if (copy_from_user(&ep_ref, (void __user *) arg, sizeof(int)))
+			return -EFAULT;
+		error = svc_dropparty(sock, ep_ref);
+		break;
+	default:
+		error = vcc_ioctl(sock, cmd, arg);
+	}
+
+	return error;
+}
+
+#ifdef CONFIG_COMPAT
+static int svc_compat_ioctl(struct socket *sock, unsigned int cmd,
+			    unsigned long arg)
+{
+	/* The definition of ATM_ADDPARTY uses the size of struct atm_iobuf.
+	   But actually it takes a struct sockaddr_atmsvc, which doesn't need
+	   compat handling. So all we have to do is fix up cmd... */
+	if (cmd == COMPAT_ATM_ADDPARTY)
+		cmd = ATM_ADDPARTY;
+
+	if (cmd == ATM_ADDPARTY || cmd == ATM_DROPPARTY)
+		return svc_ioctl(sock, cmd, arg);
+	else
+		return vcc_compat_ioctl(sock, cmd, arg);
+}
+#endif /* CONFIG_COMPAT */
+
+static const struct proto_ops svc_proto_ops = {
+	.family =	PF_ATMSVC,
+	.owner =	THIS_MODULE,
+
+	.release =	svc_release,
+	.bind =		svc_bind,
+	.connect =	svc_connect,
+	.socketpair =	sock_no_socketpair,
+	.accept =	svc_accept,
+	.getname =	svc_getname,
+	.poll =		vcc_poll,
+	.ioctl =	svc_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl =	svc_compat_ioctl,
+#endif
+	.listen =	svc_listen,
+	.shutdown =	svc_shutdown,
+	.setsockopt =	svc_setsockopt,
+	.getsockopt =	svc_getsockopt,
+	.sendmsg =	vcc_sendmsg,
+	.recvmsg =	vcc_recvmsg,
+	.mmap =		sock_no_mmap,
+	.sendpage =	sock_no_sendpage,
+};
+
+
+static int svc_create(struct net *net, struct socket *sock, int protocol,
+		      int kern)
+{
+	int error;
+
+	if (!net_eq(net, &init_net))
+		return -EAFNOSUPPORT;
+
+	sock->ops = &svc_proto_ops;
+	error = vcc_create(net, sock, protocol, AF_ATMSVC, kern);
+	if (error)
+		return error;
+	ATM_SD(sock)->local.sas_family = AF_ATMSVC;
+	ATM_SD(sock)->remote.sas_family = AF_ATMSVC;
+	return 0;
+}
+
+static const struct net_proto_family svc_family_ops = {
+	.family = PF_ATMSVC,
+	.create = svc_create,
+	.owner = THIS_MODULE,
+};
+
+
+/*
+ *	Initialize the ATM SVC protocol family
+ */
+
+int __init atmsvc_init(void)
+{
+	return sock_register(&svc_family_ops);
+}
+
+void atmsvc_exit(void)
+{
+	sock_unregister(PF_ATMSVC);
+}