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Commit 991fb3f7 authored by Nicolas Dichtel's avatar Nicolas Dichtel Committed by David S. Miller
Browse files

dev: always advertise rx_flags changes via netlink 



When flags IFF_PROMISC and IFF_ALLMULTI are changed, netlink messages are not
consistent. For example, if a multicast daemon is running (flag IFF_ALLMULTI
set in dev->flags but not dev->gflags, ie not exported to userspace) and then a
user sets it via netlink (flag IFF_ALLMULTI set in dev->flags and dev->gflags, ie
exported to userspace), no netlink message is sent.
Same for IFF_PROMISC and because dev->promiscuity is exported via
IFLA_PROMISCUITY, we may send a netlink message after each change of this
counter.

Signed-off-by: default avatarNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a528c219

net/core/dev.c

+37 −23
Original line number Diff line number Diff line
@@ -4988,7 +4988,7 @@ static void dev_change_rx_flags(struct net_device *dev, int flags) 
		ops->ndo_change_rx_flags(dev, flags);

}



static int __dev_set_promiscuity(struct net_device *dev, int inc)

static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)

{

	unsigned int old_flags = dev->flags;

	kuid_t uid;
@@ -5031,6 +5031,8 @@ static int __dev_set_promiscuity(struct net_device *dev, int inc) 


		dev_change_rx_flags(dev, IFF_PROMISC);

	}

	if (notify)

		__dev_notify_flags(dev, old_flags, IFF_PROMISC);

	return 0;

}
@@ -5050,7 +5052,7 @@ int dev_set_promiscuity(struct net_device *dev, int inc) 
	unsigned int old_flags = dev->flags;

	int err;



	err = __dev_set_promiscuity(dev, inc);

	err = __dev_set_promiscuity(dev, inc, true);

	if (err < 0)

		return err;

	if (dev->flags != old_flags)
@@ -5059,22 +5061,9 @@ int dev_set_promiscuity(struct net_device *dev, int inc) 
}

EXPORT_SYMBOL(dev_set_promiscuity);



/**

 *	dev_set_allmulti	- update allmulti count on a device

 *	@dev: device

 *	@inc: modifier

 *

 *	Add or remove reception of all multicast frames to a device. While the

 *	count in the device remains above zero the interface remains listening

 *	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.

 */



int dev_set_allmulti(struct net_device *dev, int inc)

static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)

{

	unsigned int old_flags = dev->flags;

	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;



	ASSERT_RTNL();
@@ -5097,9 +5086,30 @@ int dev_set_allmulti(struct net_device *dev, int inc) 
	if (dev->flags ^ old_flags) {

		dev_change_rx_flags(dev, IFF_ALLMULTI);

		dev_set_rx_mode(dev);

		if (notify)

			__dev_notify_flags(dev, old_flags,

					   dev->gflags ^ old_gflags);

	}

	return 0;

}



/**

 *	dev_set_allmulti	- update allmulti count on a device

 *	@dev: device

 *	@inc: modifier

 *

 *	Add or remove reception of all multicast frames to a device. While the

 *	count in the device remains above zero the interface remains listening

 *	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.

 */



int dev_set_allmulti(struct net_device *dev, int inc)

{

	return __dev_set_allmulti(dev, inc, true);

}

EXPORT_SYMBOL(dev_set_allmulti);



/*
@@ -5124,10 +5134,10 @@ void __dev_set_rx_mode(struct net_device *dev) 
		 * therefore calling __dev_set_promiscuity here is safe.

		 */

		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {

			__dev_set_promiscuity(dev, 1);

			__dev_set_promiscuity(dev, 1, false);

			dev->uc_promisc = true;

		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {

			__dev_set_promiscuity(dev, -1);

			__dev_set_promiscuity(dev, -1, false);

			dev->uc_promisc = false;

		}

	}
@@ -5216,9 +5226,13 @@ int __dev_change_flags(struct net_device *dev, unsigned int flags) 


	if ((flags ^ dev->gflags) & IFF_PROMISC) {

		int inc = (flags & IFF_PROMISC) ? 1 : -1;

		unsigned int old_flags = dev->flags;



		dev->gflags ^= IFF_PROMISC;

		dev_set_promiscuity(dev, inc);



		if (__dev_set_promiscuity(dev, inc, false) >= 0)

			if (dev->flags != old_flags)

				dev_set_rx_mode(dev);

	}



	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
@@ -5229,7 +5243,7 @@ int __dev_change_flags(struct net_device *dev, unsigned int flags) 
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;



		dev->gflags ^= IFF_ALLMULTI;

		dev_set_allmulti(dev, inc);

		__dev_set_allmulti(dev, inc, false);

	}



	return ret;
@@ -5271,13 +5285,13 @@ void __dev_notify_flags(struct net_device *dev, unsigned int old_flags, 
int dev_change_flags(struct net_device *dev, unsigned int flags)

{

	int ret;

	unsigned int changes, old_flags = dev->flags;

	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;



	ret = __dev_change_flags(dev, flags);

	if (ret < 0)

		return ret;



	changes = old_flags ^ dev->flags;

	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);

	__dev_notify_flags(dev, old_flags, changes);

	return ret;

}