---

yaml
---
r: 103065
b: refs/heads/master
c: dad9b33
h: refs/heads/master
i:
  103063: 61e617c
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: dd574dbfcc9e74e7dd8fd59ae0075d23e71a3da1
+refs/heads/master: dad9b335c6940de2746a9788eb456d09cf102f81

trunk/include/linux/netdevice.h

@@ -1476,8 +1476,8 @@ extern int 		__dev_addr_delete(struct dev_addr_list **list, int *count, void *ad
 extern int		__dev_addr_add(struct dev_addr_list **list, int *count, void *addr, int alen, int newonly);
 extern int		__dev_addr_sync(struct dev_addr_list **to, int *to_count, struct dev_addr_list **from, int *from_count);
 extern void		__dev_addr_unsync(struct dev_addr_list **to, int *to_count, struct dev_addr_list **from, int *from_count);
-extern void		dev_set_promiscuity(struct net_device *dev, int inc);
-extern void		dev_set_allmulti(struct net_device *dev, int inc);
+extern int		dev_set_promiscuity(struct net_device *dev, int inc);
+extern int		dev_set_allmulti(struct net_device *dev, int inc);
 extern void		netdev_state_change(struct net_device *dev);
 extern void		netdev_bonding_change(struct net_device *dev);
 extern void		netdev_features_change(struct net_device *dev);

trunk/net/core/dev.c

@@ -2771,16 +2771,29 @@ int netdev_set_master(struct net_device *slave, struct net_device *master)
 	return 0;
 }
 
-static void __dev_set_promiscuity(struct net_device *dev, int inc)
+static int __dev_set_promiscuity(struct net_device *dev, int inc)
 {
 	unsigned short old_flags = dev->flags;
 
 	ASSERT_RTNL();
 
-	if ((dev->promiscuity += inc) == 0)
-		dev->flags &= ~IFF_PROMISC;
-	else
-		dev->flags |= IFF_PROMISC;
+	dev->flags |= IFF_PROMISC;
+	dev->promiscuity += inc;
+	if (dev->promiscuity == 0) {
+		/*
+		 * Avoid overflow.
+		 * If inc causes overflow, untouch promisc and return error.
+		 */
+		if (inc < 0)
+			dev->flags &= ~IFF_PROMISC;
+		else {
+			dev->promiscuity -= inc;
+			printk(KERN_WARNING "%s: promiscuity touches roof, "
+				"set promiscuity failed, promiscuity feature "
+				"of device might be broken.\n", dev->name);
+			return -EOVERFLOW;
+		}
+	}
 	if (dev->flags != old_flags) {
 		printk(KERN_INFO "device %s %s promiscuous mode\n",
 		       dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
@@ -2798,6 +2811,7 @@ static void __dev_set_promiscuity(struct net_device *dev, int inc)
 		if (dev->change_rx_flags)
 			dev->change_rx_flags(dev, IFF_PROMISC);
 	}
+	return 0;
 }
 
 /**
@@ -2809,14 +2823,19 @@ static void __dev_set_promiscuity(struct net_device *dev, int inc)
  *	remains above zero the interface remains promiscuous. Once it hits zero
  *	the device reverts back to normal filtering operation. A negative inc
  *	value is used to drop promiscuity on the device.
+ *	Return 0 if successful or a negative errno code on error.
  */
-void dev_set_promiscuity(struct net_device *dev, int inc)
+int dev_set_promiscuity(struct net_device *dev, int inc)
 {
 	unsigned short old_flags = dev->flags;
+	int err;
 
-	__dev_set_promiscuity(dev, inc);
+	err = __dev_set_promiscuity(dev, inc);
+	if (!err)
+		return err;
 	if (dev->flags != old_flags)
 		dev_set_rx_mode(dev);
+	return err;
 }
 
 /**
@@ -2829,22 +2848,38 @@ void dev_set_promiscuity(struct net_device *dev, int inc)
  *	to all interfaces. Once it hits zero the device reverts back to normal
  *	filtering operation. A negative @inc value is used to drop the counter
  *	when releasing a resource needing all multicasts.
+ *	Return 0 if successful or a negative errno code on error.
  */
 
-void dev_set_allmulti(struct net_device *dev, int inc)
+int dev_set_allmulti(struct net_device *dev, int inc)
 {
 	unsigned short old_flags = dev->flags;
 
 	ASSERT_RTNL();
 
 	dev->flags |= IFF_ALLMULTI;
-	if ((dev->allmulti += inc) == 0)
-		dev->flags &= ~IFF_ALLMULTI;
+	dev->allmulti += inc;
+	if (dev->allmulti == 0) {
+		/*
+		 * Avoid overflow.
+		 * If inc causes overflow, untouch allmulti and return error.
+		 */
+		if (inc < 0)
+			dev->flags &= ~IFF_ALLMULTI;
+		else {
+			dev->allmulti -= inc;
+			printk(KERN_WARNING "%s: allmulti touches roof, "
+				"set allmulti failed, allmulti feature of "
+				"device might be broken.\n", dev->name);
+			return -EOVERFLOW;
+		}
+	}
 	if (dev->flags ^ old_flags) {
 		if (dev->change_rx_flags)
 			dev->change_rx_flags(dev, IFF_ALLMULTI);
 		dev_set_rx_mode(dev);
 	}
+	return 0;
 }
 
 /*