dev_ioctl: pass SIOCDEVPRIVATE data separately

The compat handlers for SIOCDEVPRIVATE are incorrect for any driver that
passes data as part of struct ifreq rather than as an ifr_data pointer, or
that passes data back this way, since the compat_ifr_data_ioctl() helper
overwrites the ifr_data pointer and does not copy anything back out.

Since all drivers using devprivate commands are now converted to the
new .ndo_siocdevprivate callback, fix this by adding the missing piece
and passing the pointer separately the whole way.

This further unifies the native and compat logic for socket ioctls,
as the new code now passes the correct pointer as well as the correct
data for both native and compat ioctls.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 10 deletions

diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
index 75e3e340d884..3ace1e4f6b80 100644
--- a/net/core/dev_ioctl.c
+++ b/net/core/dev_ioctl.c
@@ -259,11 +259,10 @@ static int dev_do_ioctl(struct net_device *dev,
 	return err;
 }
 
-static int dev_siocdevprivate(struct net_device *dev,
-			      struct ifreq *ifr, unsigned int cmd)
+static int dev_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
+			      void __user *data, unsigned int cmd)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
-	void __user *data = ifr->ifr_data;
 
 	if (ops->ndo_siocdevprivate) {
 		if (netif_device_present(dev))
@@ -273,13 +272,15 @@ static int dev_siocdevprivate(struct net_device *dev,
 	}
 
 	/* fall back to do_ioctl for drivers not yet converted */
+	ifr->ifr_data = data;
 	return dev_do_ioctl(dev, ifr, cmd);
 }
 
 /*
  *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
  */
-static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
+static int dev_ifsioc(struct net *net, struct ifreq *ifr, void __user *data,
+		      unsigned int cmd)
 {
 	int err;
 	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
@@ -355,7 +356,7 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
 	default:
 		if (cmd >= SIOCDEVPRIVATE &&
 		    cmd <= SIOCDEVPRIVATE + 15)
-			return dev_siocdevprivate(dev, ifr, cmd);
+			return dev_siocdevprivate(dev, ifr, data, cmd);
 
 		if (cmd == SIOCBONDENSLAVE ||
 		    cmd == SIOCBONDRELEASE ||
@@ -424,7 +425,8 @@ EXPORT_SYMBOL(dev_load);
  *	positive or a negative errno code on error.
  */
 
-int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_copyout)
+int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr,
+	      void __user *data, bool *need_copyout)
 {
 	int ret;
 	char *colon;
@@ -475,7 +477,7 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_c
 	case SIOCETHTOOL:
 		dev_load(net, ifr->ifr_name);
 		rtnl_lock();
-		ret = dev_ethtool(net, ifr);
+		ret = dev_ethtool(net, ifr, data);
 		rtnl_unlock();
 		if (colon)
 			*colon = ':';
@@ -494,7 +496,7 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_c
 		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 			return -EPERM;
 		rtnl_lock();
-		ret = dev_ifsioc(net, ifr, cmd);
+		ret = dev_ifsioc(net, ifr, data, cmd);
 		rtnl_unlock();
 		if (colon)
 			*colon = ':';
@@ -540,7 +542,7 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_c
 	case SIOCBONDINFOQUERY:
 		dev_load(net, ifr->ifr_name);
 		rtnl_lock();
-		ret = dev_ifsioc(net, ifr, cmd);
+		ret = dev_ifsioc(net, ifr, data, cmd);
 		rtnl_unlock();
 		if (need_copyout)
 			*need_copyout = false;
@@ -565,7 +567,7 @@ int dev_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr, bool *need_c
 		     cmd <= SIOCDEVPRIVATE + 15)) {
 			dev_load(net, ifr->ifr_name);
 			rtnl_lock();
-			ret = dev_ifsioc(net, ifr, cmd);
+			ret = dev_ifsioc(net, ifr, data, cmd);
 			rtnl_unlock();
 			return ret;
 		}