Subject: [RFC net-next 14/28] fddi: use ndo_siocdevprivate

From: Arnd Bergmann <[email-masked]>
Date: Fri, 6 Nov 2020 23:17:29 +0100

From: Arnd Bergmann <[email-masked]>

The skfddi driver has a private ioctl and passes the data correctly
through ifr_data, but the use of a pointer in s_skfp_ioctl is
broken in compat mode.

Change the driver to use ndo_siocdevprivate and disallow calling
it in compat mode until a conversion handler is added.

Signed-off-by: Arnd Bergmann <[email-masked]>
---
 drivers/net/fddi/skfp/skfddi.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/net/fddi/skfp/skfddi.c b/drivers/net/fddi/skfp/skfddi.c
index 69c29a2ef95d..fe3b1d041142 100644
--- a/drivers/net/fddi/skfp/skfddi.c
+++ b/drivers/net/fddi/skfp/skfddi.c
@@ -103,7 +103,8 @@ static struct net_device_stats *skfp_ctl_get_stats(struct net_device *dev);
 static void skfp_ctl_set_multicast_list(struct net_device *dev);
 static void skfp_ctl_set_multicast_list_wo_lock(struct net_device *dev);
 static int skfp_ctl_set_mac_address(struct net_device *dev, void *addr);
-static int skfp_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
+static int skfp_siocdevprivate(struct net_device *dev, struct ifreq *rq,
+			       void __user *data, int cmd);
 static netdev_tx_t skfp_send_pkt(struct sk_buff *skb,
 				       struct net_device *dev);
 static void send_queued_packets(struct s_smc *smc);
@@ -164,7 +165,7 @@ static const struct net_device_ops skfp_netdev_ops = {
 	.ndo_get_stats		= skfp_ctl_get_stats,
 	.ndo_set_rx_mode	= skfp_ctl_set_multicast_list,
 	.ndo_set_mac_address	= skfp_ctl_set_mac_address,
-	.ndo_do_ioctl		= skfp_ioctl,
+	.ndo_siocdevprivate	= skfp_siocdevprivate,
 };
 
 /*
@@ -932,9 +933,9 @@ static int skfp_ctl_set_mac_address(struct net_device *dev, void *addr)

 /*
- * ==============
- * = skfp_ioctl =
- * ==============
+ * =======================
+ * = skfp_siocdevprivate =
+ * =======================
  *   
  * Overview:
  *
@@ -954,16 +955,19 @@ static int skfp_ctl_set_mac_address(struct net_device *dev, void *addr)
  */

-static int skfp_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+static int skfp_siocdevprivate(struct net_device *dev, struct ifreq *rq, void __user *data, int cmd)
 {
 	struct s_smc *smc = netdev_priv(dev);
 	skfddi_priv *lp = &smc->os;
 	struct s_skfp_ioctl ioc;
 	int status = 0;
 
-	if (copy_from_user(&ioc, rq->ifr_data, sizeof(struct s_skfp_ioctl)))
+	if (copy_from_user(&ioc, data, sizeof(struct s_skfp_ioctl)))
 		return -EFAULT;
 
+	if (in_compat_syscall())
+		return -EOPNOTSUPP;
+
 	switch (ioc.cmd) {
 	case SKFP_GET_STATS:	/* Get the driver statistics */
 		ioc.len = sizeof(lp->MacStat);
-- 
2.27.0