FAILED: Patch "usb: gadget: f_ncm: align net_device lifecycle with bind/unbind" failed to apply to 5.15-stable tree

index 0e38330271d5a..e23adc132f886 100644
@@ -83,6 +83,11 @@ static inline struct f_ncm *func_to_ncm(struct usb_function *f)
 	return container_of(f, struct f_ncm, port.func);
 }
 
+static inline struct f_ncm_opts *func_to_ncm_opts(struct usb_function *f)
+{
+	return container_of(f->fi, struct f_ncm_opts, func_inst);
+}
+
 /*-------------------------------------------------------------------------*/
 
 /*

@@ -859,6 +864,7 @@ static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 {
 	struct f_ncm		*ncm = func_to_ncm(f);
+	struct f_ncm_opts	*opts = func_to_ncm_opts(f);
 	struct usb_composite_dev *cdev = f->config->cdev;
 
 	/* Control interface has only altsetting 0 */

@@ -881,12 +887,13 @@ static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 		if (alt > 1)
 			goto fail;
 
-		if (ncm->netdev) {
-			DBG(cdev, "reset ncm\n");
-			ncm->netdev = NULL;
-			gether_disconnect(&ncm->port);
-			ncm_reset_values(ncm);
-		}
+		scoped_guard(mutex, &opts->lock)
+			if (opts->net) {
+				DBG(cdev, "reset ncm\n");
+				opts->net = NULL;
+				gether_disconnect(&ncm->port);
+				ncm_reset_values(ncm);
+			}
 
 		/*
 		 * CDC Network only sends data in non-default altsettings.

@@ -919,7 +926,8 @@ static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 			net = gether_connect(&ncm->port);
 			if (IS_ERR(net))
 				return PTR_ERR(net);
-			ncm->netdev = net;
+			scoped_guard(mutex, &opts->lock)
+				opts->net = net;
 		}
 
 		spin_lock(&ncm->lock);

@@ -1366,14 +1374,16 @@ static int ncm_unwrap_ntb(struct gether *port,
 static void ncm_disable(struct usb_function *f)
 {
 	struct f_ncm		*ncm = func_to_ncm(f);
+	struct f_ncm_opts	*opts = func_to_ncm_opts(f);
 	struct usb_composite_dev *cdev = f->config->cdev;
 
 	DBG(cdev, "ncm deactivated\n");
 
-	if (ncm->netdev) {
-		ncm->netdev = NULL;
-		gether_disconnect(&ncm->port);
-	}
+	scoped_guard(mutex, &opts->lock)
+		if (opts->net) {
+			opts->net = NULL;
+			gether_disconnect(&ncm->port);
+		}
 
 	if (ncm->notify->enabled) {
 		usb_ep_disable(ncm->notify);

@@ -1433,39 +1443,44 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct usb_composite_dev *cdev = c->cdev;
 	struct f_ncm		*ncm = func_to_ncm(f);
+	struct f_ncm_opts	*ncm_opts = func_to_ncm_opts(f);
 	struct usb_string	*us;
 	int			status = 0;
 	struct usb_ep		*ep;
-	struct f_ncm_opts	*ncm_opts;
 
 	struct usb_os_desc_table	*os_desc_table __free(kfree) = NULL;
+	struct net_device		*netdev __free(free_gether_netdev) = NULL;
 	struct usb_request		*request __free(free_usb_request) = NULL;
 
 	if (!can_support_ecm(cdev->gadget))
 		return -EINVAL;
 
-	ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
-
 	if (cdev->use_os_string) {
 		os_desc_table = kzalloc(sizeof(*os_desc_table), GFP_KERNEL);
 		if (!os_desc_table)
 			return -ENOMEM;
 	}
 
-	mutex_lock(&ncm_opts->lock);
-	gether_set_gadget(ncm_opts->net, cdev->gadget);
-	if (!ncm_opts->bound) {
-		ncm_opts->net->mtu = (ncm_opts->max_segment_size - ETH_HLEN);
-		status = gether_register_netdev(ncm_opts->net);
+	netdev = gether_setup_default();
+	if (IS_ERR(netdev))
+		return -ENOMEM;
+
+	scoped_guard(mutex, &ncm_opts->lock) {
+		gether_apply_opts(netdev, &ncm_opts->net_opts);
+		netdev->mtu = ncm_opts->max_segment_size - ETH_HLEN;
 	}
-	mutex_unlock(&ncm_opts->lock);
 
+	gether_set_gadget(netdev, cdev->gadget);
+	status = gether_register_netdev(netdev);
 	if (status)
 		return status;
 
-	ncm_opts->bound = true;
-
-	ncm_string_defs[1].s = ncm->ethaddr;
+	/* export host's Ethernet address in CDC format */
+	status = gether_get_host_addr_cdc(netdev, ncm->ethaddr,
+					  sizeof(ncm->ethaddr));
+	if (status < 12)
+		return -EINVAL;
+	ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
 
 	us = usb_gstrings_attach(cdev, ncm_strings,
 				 ARRAY_SIZE(ncm_string_defs));

@@ -1563,6 +1578,8 @@ static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
 		f->os_desc_n = 1;
 	}
 	ncm->notify_req = no_free_ptr(request);
+	ncm->netdev = no_free_ptr(netdev);
+	ncm->port.ioport = netdev_priv(ncm->netdev);
 
 	DBG(cdev, "CDC Network: IN/%s OUT/%s NOTIFY/%s\n",
 			ncm->port.in_ep->name, ncm->port.out_ep->name,

@@ -1577,19 +1594,19 @@ static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
 }
 
 /* f_ncm_item_ops */
-USB_ETHERNET_CONFIGFS_ITEM(ncm);
+USB_ETHER_OPTS_ITEM(ncm);
 
 /* f_ncm_opts_dev_addr */
-USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
+USB_ETHER_OPTS_ATTR_DEV_ADDR(ncm);
 
 /* f_ncm_opts_host_addr */
-USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
+USB_ETHER_OPTS_ATTR_HOST_ADDR(ncm);
 
 /* f_ncm_opts_qmult */
-USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
+USB_ETHER_OPTS_ATTR_QMULT(ncm);
 
 /* f_ncm_opts_ifname */
-USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
+USB_ETHER_OPTS_ATTR_IFNAME(ncm);
 
 static ssize_t ncm_opts_max_segment_size_show(struct config_item *item,
 					      char *page)

@@ -1655,34 +1672,27 @@ static void ncm_free_inst(struct usb_function_instance *f)
 	struct f_ncm_opts *opts;
 
 	opts = container_of(f, struct f_ncm_opts, func_inst);
-	if (opts->bound)
-		gether_cleanup(netdev_priv(opts->net));
-	else
-		free_netdev(opts->net);
 	kfree(opts->ncm_interf_group);
 	kfree(opts);
 }
 
 static struct usb_function_instance *ncm_alloc_inst(void)
 {
-	struct f_ncm_opts *opts;
+	struct usb_function_instance *ret;
 	struct usb_os_desc *descs[1];
 	char *names[1];
 	struct config_group *ncm_interf_group;
 
-	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+	struct f_ncm_opts *opts __free(kfree) = kzalloc(sizeof(*opts), GFP_KERNEL);
 	if (!opts)
 		return ERR_PTR(-ENOMEM);
+
+	opts->net = NULL;
 	opts->ncm_os_desc.ext_compat_id = opts->ncm_ext_compat_id;
+	gether_setup_opts_default(&opts->net_opts, "usb");
 
 	mutex_init(&opts->lock);
 	opts->func_inst.free_func_inst = ncm_free_inst;
-	opts->net = gether_setup_default();
-	if (IS_ERR(opts->net)) {
-		struct net_device *net = opts->net;
-		kfree(opts);
-		return ERR_CAST(net);
-	}
 	opts->max_segment_size = ETH_FRAME_LEN;
 	INIT_LIST_HEAD(&opts->ncm_os_desc.ext_prop);
 

@@ -1693,26 +1703,22 @@ static struct usb_function_instance *ncm_alloc_inst(void)
 	ncm_interf_group =
 		usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
 					       names, THIS_MODULE);
-	if (IS_ERR(ncm_interf_group)) {
-		ncm_free_inst(&opts->func_inst);
+	if (IS_ERR(ncm_interf_group))
 		return ERR_CAST(ncm_interf_group);
-	}
 	opts->ncm_interf_group = ncm_interf_group;
 
-	return &opts->func_inst;
+	ret = &opts->func_inst;
+	retain_and_null_ptr(opts);
+	return ret;
 }
 
 static void ncm_free(struct usb_function *f)
 {
-	struct f_ncm *ncm;
-	struct f_ncm_opts *opts;
+	struct f_ncm_opts *opts = func_to_ncm_opts(f);
 
-	ncm = func_to_ncm(f);
-	opts = container_of(f->fi, struct f_ncm_opts, func_inst);
-	kfree(ncm);
-	mutex_lock(&opts->lock);
-	opts->refcnt--;
-	mutex_unlock(&opts->lock);
+	scoped_guard(mutex, &opts->lock)
+		opts->refcnt--;
+	kfree(func_to_ncm(f));
 }
 
 static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)

@@ -1736,13 +1742,15 @@ static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
 
 	kfree(ncm->notify_req->buf);
 	usb_ep_free_request(ncm->notify, ncm->notify_req);
+
+	ncm->port.ioport = NULL;
+	gether_cleanup(netdev_priv(ncm->netdev));
 }
 
 static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
 {
 	struct f_ncm		*ncm;
 	struct f_ncm_opts	*opts;
-	int status;
 
 	/* allocate and initialize one new instance */
 	ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);

@@ -1750,22 +1758,12 @@ static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
 		return ERR_PTR(-ENOMEM);
 
 	opts = container_of(fi, struct f_ncm_opts, func_inst);
-	mutex_lock(&opts->lock);
-	opts->refcnt++;
 
-	/* export host's Ethernet address in CDC format */
-	status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
-				      sizeof(ncm->ethaddr));
-	if (status < 12) { /* strlen("01234567890a") */
-		kfree(ncm);
-		mutex_unlock(&opts->lock);
-		return ERR_PTR(-EINVAL);
-	}
+	scoped_guard(mutex, &opts->lock)
+		opts->refcnt++;
 
 	spin_lock_init(&ncm->lock);
 	ncm_reset_values(ncm);
-	ncm->port.ioport = netdev_priv(opts->net);
-	mutex_unlock(&opts->lock);
 	ncm->port.is_fixed = true;
 	ncm->port.supports_multi_frame = true;
 

index 49ec095cdb4b6..d99330fe31e88 100644
@@ -15,11 +15,13 @@
 
 #include <linux/usb/composite.h>
 
+#include "u_ether.h"
+
 struct f_ncm_opts {
 	struct usb_function_instance	func_inst;
 	struct net_device		*net;
-	bool				bound;
 
+	struct gether_opts		net_opts;
 	struct config_group		*ncm_interf_group;
 	struct usb_os_desc		ncm_os_desc;
 	char				ncm_ext_compat_id[16];