1 files changed, 140 insertions, 50 deletions

diff --git a/drivers/usb/usbip/stub_main.c b/drivers/usb/usbip/stub_main.c
index 660180a5d5c4..79110a69d697 100644
--- a/drivers/usb/usbip/stub_main.c
+++ b/drivers/usb/usbip/stub_main.c
@@ -1,25 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright (C) 2003-2008 Takahiro Hirofuchi
- *
- * This is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
- * USA.
  */
 
 #include <linux/string.h>
 #include <linux/module.h>
 #include <linux/device.h>
+#include <linux/scatterlist.h>
 
 #include "usbip_common.h"
 #include "stub.h"
@@ -28,6 +15,7 @@
 #define DRIVER_DESC "USB/IP Host Driver"
 
 struct kmem_cache *stub_priv_cache;
+
 /*
  * busid_tables defines matching busids that usbip can grab. A user can change
  * dynamically what device is locally used and what device is exported to a
@@ -35,17 +23,20 @@ struct kmem_cache *stub_priv_cache;
  */
 #define MAX_BUSID 16
 static struct bus_id_priv busid_table[MAX_BUSID];
-static spinlock_t busid_table_lock;
+static DEFINE_SPINLOCK(busid_table_lock);
 
 static void init_busid_table(void)
 {
+	int i;
+
 	/*
 	 * This also sets the bus_table[i].status to
 	 * STUB_BUSID_OTHER, which is 0.
 	 */
 	memset(busid_table, 0, sizeof(busid_table));
 
-	spin_lock_init(&busid_table_lock);
+	for (i = 0; i < MAX_BUSID; i++)
+		spin_lock_init(&busid_table[i].busid_lock);
 }
 
 /*
@@ -57,15 +48,20 @@ static int get_busid_idx(const char *busid)
 	int i;
 	int idx = -1;
 
-	for (i = 0; i < MAX_BUSID; i++)
+	for (i = 0; i < MAX_BUSID; i++) {
+		spin_lock(&busid_table[i].busid_lock);
 		if (busid_table[i].name[0])
 			if (!strncmp(busid_table[i].name, busid, BUSID_SIZE)) {
 				idx = i;
+				spin_unlock(&busid_table[i].busid_lock);
 				break;
 			}
+		spin_unlock(&busid_table[i].busid_lock);
+	}
 	return idx;
 }
 
+/* Returns holding busid_lock. Should call put_busid_priv() to unlock */
 struct bus_id_priv *get_busid_priv(const char *busid)
 {
 	int idx;
@@ -73,13 +69,22 @@ struct bus_id_priv *get_busid_priv(const char *busid)
 
 	spin_lock(&busid_table_lock);
 	idx = get_busid_idx(busid);
-	if (idx >= 0)
+	if (idx >= 0) {
 		bid = &(busid_table[idx]);
+		/* get busid_lock before returning */
+		spin_lock(&bid->busid_lock);
+	}
 	spin_unlock(&busid_table_lock);
 
 	return bid;
 }
 
+void put_busid_priv(struct bus_id_priv *bid)
+{
+	if (bid)
+		spin_unlock(&bid->busid_lock);
+}
+
 static int add_match_busid(char *busid)
 {
 	int i;
@@ -92,15 +97,19 @@ static int add_match_busid(char *busid)
 		goto out;
 	}
 
-	for (i = 0; i < MAX_BUSID; i++)
+	for (i = 0; i < MAX_BUSID; i++) {
+		spin_lock(&busid_table[i].busid_lock);
 		if (!busid_table[i].name[0]) {
-			strlcpy(busid_table[i].name, busid, BUSID_SIZE);
+			strscpy(busid_table[i].name, busid, BUSID_SIZE);
 			if ((busid_table[i].status != STUB_BUSID_ALLOC) &&
 			    (busid_table[i].status != STUB_BUSID_REMOV))
 				busid_table[i].status = STUB_BUSID_ADDED;
 			ret = 0;
+			spin_unlock(&busid_table[i].busid_lock);
 			break;
 		}
+		spin_unlock(&busid_table[i].busid_lock);
+	}
 
 out:
 	spin_unlock(&busid_table_lock);
@@ -121,6 +130,8 @@ int del_match_busid(char *busid)
 	/* found */
 	ret = 0;
 
+	spin_lock(&busid_table[idx].busid_lock);
+
 	if (busid_table[idx].status == STUB_BUSID_OTHER)
 		memset(busid_table[idx].name, 0, BUSID_SIZE);
 
@@ -128,6 +139,7 @@ int del_match_busid(char *busid)
 	    (busid_table[idx].status != STUB_BUSID_ADDED))
 		busid_table[idx].status = STUB_BUSID_REMOV;
 
+	spin_unlock(&busid_table[idx].busid_lock);
 out:
 	spin_unlock(&busid_table_lock);
 
@@ -140,9 +152,12 @@ static ssize_t match_busid_show(struct device_driver *drv, char *buf)
 	char *out = buf;
 
 	spin_lock(&busid_table_lock);
-	for (i = 0; i < MAX_BUSID; i++)
+	for (i = 0; i < MAX_BUSID; i++) {
+		spin_lock(&busid_table[i].busid_lock);
 		if (busid_table[i].name[0])
 			out += sprintf(out, "%s ", busid_table[i].name);
+		spin_unlock(&busid_table[i].busid_lock);
+	}
 	spin_unlock(&busid_table_lock);
 	out += sprintf(out, "\n");
 
@@ -152,15 +167,13 @@ static ssize_t match_busid_show(struct device_driver *drv, char *buf)
 static ssize_t match_busid_store(struct device_driver *dev, const char *buf,
 				 size_t count)
 {
-	int len;
 	char busid[BUSID_SIZE];
 
 	if (count < 5)
 		return -EINVAL;
 
 	/* busid needs to include \0 termination */
-	len = strlcpy(busid, buf + 4, BUSID_SIZE);
-	if (sizeof(busid) <= len)
+	if (strscpy(busid, buf + 4, BUSID_SIZE) < 0)
 		return -EINVAL;
 
 	if (!strncmp(buf, "add ", 4)) {
@@ -183,6 +196,49 @@ static ssize_t match_busid_store(struct device_driver *dev, const char *buf,
 }
 static DRIVER_ATTR_RW(match_busid);
 
+static int do_rebind(char *busid, struct bus_id_priv *busid_priv)
+{
+	int ret = 0;
+
+	/* device_attach() callers should hold parent lock for USB */
+	if (busid_priv->udev->dev.parent)
+		device_lock(busid_priv->udev->dev.parent);
+	ret = device_attach(&busid_priv->udev->dev);
+	if (busid_priv->udev->dev.parent)
+		device_unlock(busid_priv->udev->dev.parent);
+	if (ret < 0)
+		dev_err(&busid_priv->udev->dev, "rebind failed\n");
+	return ret;
+}
+
+static void stub_device_rebind(void)
+{
+#if IS_MODULE(CONFIG_USBIP_HOST)
+	struct bus_id_priv *busid_priv;
+	int i;
+
+	/* update status to STUB_BUSID_OTHER so probe ignores the device */
+	spin_lock(&busid_table_lock);
+	for (i = 0; i < MAX_BUSID; i++) {
+		if (busid_table[i].name[0] &&
+		    busid_table[i].shutdown_busid) {
+			busid_priv = &(busid_table[i]);
+			busid_priv->status = STUB_BUSID_OTHER;
+		}
+	}
+	spin_unlock(&busid_table_lock);
+
+	/* now run rebind - no need to hold locks. driver files are removed */
+	for (i = 0; i < MAX_BUSID; i++) {
+		if (busid_table[i].name[0] &&
+		    busid_table[i].shutdown_busid) {
+			busid_priv = &(busid_table[i]);
+			do_rebind(busid_table[i].name, busid_priv);
+		}
+	}
+#endif
+}
+
 static ssize_t rebind_store(struct device_driver *dev, const char *buf,
 				 size_t count)
 {
@@ -200,11 +256,17 @@ static ssize_t rebind_store(struct device_driver *dev, const char *buf,
 	if (!bid)
 		return -ENODEV;
 
-	ret = device_attach(&bid->udev->dev);
-	if (ret < 0) {
-		dev_err(&bid->udev->dev, "rebind failed\n");
+	/* mark the device for deletion so probe ignores it during rescan */
+	bid->status = STUB_BUSID_OTHER;
+	/* release the busid lock */
+	put_busid_priv(bid);
+
+	ret = do_rebind((char *) buf, bid);
+	if (ret < 0)
 		return ret;
-	}
+
+	/* delete device from busid_table */
+	del_match_busid((char *) buf);
 
 	return count;
 }
@@ -216,13 +278,49 @@ static struct stub_priv *stub_priv_pop_from_listhead(struct list_head *listhead)
 	struct stub_priv *priv, *tmp;
 
 	list_for_each_entry_safe(priv, tmp, listhead, list) {
-		list_del(&priv->list);
+		list_del_init(&priv->list);
 		return priv;
 	}
 
 	return NULL;
 }
 
+void stub_free_priv_and_urb(struct stub_priv *priv)
+{
+	struct urb *urb;
+	int i;
+
+	for (i = 0; i < priv->num_urbs; i++) {
+		urb = priv->urbs[i];
+
+		if (!urb)
+			return;
+
+		kfree(urb->setup_packet);
+		urb->setup_packet = NULL;
+
+
+		if (urb->transfer_buffer && !priv->sgl) {
+			kfree(urb->transfer_buffer);
+			urb->transfer_buffer = NULL;
+		}
+
+		if (urb->num_sgs) {
+			sgl_free(urb->sg);
+			urb->sg = NULL;
+			urb->num_sgs = 0;
+		}
+
+		usb_free_urb(urb);
+	}
+	if (!list_empty(&priv->list))
+		list_del(&priv->list);
+	if (priv->sgl)
+		sgl_free(priv->sgl);
+	kfree(priv->urbs);
+	kmem_cache_free(stub_priv_cache, priv);
+}
+
 static struct stub_priv *stub_priv_pop(struct stub_device *sdev)
 {
 	unsigned long flags;
@@ -249,24 +347,15 @@ done:
 void stub_device_cleanup_urbs(struct stub_device *sdev)
 {
 	struct stub_priv *priv;
-	struct urb *urb;
+	int i;
 
-	dev_dbg(&sdev->udev->dev, "free sdev %p\n", sdev);
+	dev_dbg(&sdev->udev->dev, "Stub device cleaning up urbs\n");
 
 	while ((priv = stub_priv_pop(sdev))) {
-		urb = priv->urb;
-		dev_dbg(&sdev->udev->dev, "free urb %p\n", urb);
-		usb_kill_urb(urb);
-
-		kmem_cache_free(stub_priv_cache, priv);
-
-		kfree(urb->transfer_buffer);
-		urb->transfer_buffer = NULL;
-
-		kfree(urb->setup_packet);
-		urb->setup_packet = NULL;
+		for (i = 0; i < priv->num_urbs; i++)
+			usb_kill_urb(priv->urbs[i]);
 
-		usb_free_urb(urb);
+		stub_free_priv_and_urb(priv);
 	}
 }
 
@@ -288,21 +377,20 @@ static int __init usbip_host_init(void)
 		goto err_usb_register;
 	}
 
-	ret = driver_create_file(&stub_driver.drvwrap.driver,
+	ret = driver_create_file(&stub_driver.driver,
 				 &driver_attr_match_busid);
 	if (ret) {
 		pr_err("driver_create_file failed\n");
 		goto err_create_file;
 	}
 
-	ret = driver_create_file(&stub_driver.drvwrap.driver,
+	ret = driver_create_file(&stub_driver.driver,
 				 &driver_attr_rebind);
 	if (ret) {
 		pr_err("driver_create_file failed\n");
 		goto err_create_file;
 	}
 
-	pr_info(DRIVER_DESC " v" USBIP_VERSION "\n");
 	return ret;
 
 err_create_file:
@@ -314,10 +402,10 @@ err_usb_register:
 
 static void __exit usbip_host_exit(void)
 {
-	driver_remove_file(&stub_driver.drvwrap.driver,
+	driver_remove_file(&stub_driver.driver,
 			   &driver_attr_match_busid);
 
-	driver_remove_file(&stub_driver.drvwrap.driver,
+	driver_remove_file(&stub_driver.driver,
 			   &driver_attr_rebind);
 
 	/*
@@ -326,6 +414,9 @@ static void __exit usbip_host_exit(void)
 	 */
 	usb_deregister_device_driver(&stub_driver);
 
+	/* initiate scan to attach devices */
+	stub_device_rebind();
+
 	kmem_cache_destroy(stub_priv_cache);
 }
 
@@ -335,4 +426,3 @@ module_exit(usbip_host_exit);
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL");
-MODULE_VERSION(USBIP_VERSION);