[PATCH net-next v3 09/31] appletalk: use ndo_siocdevprivate

Arnd Bergmann
2021-07-27T13:46:32Z

appletalk has three SIOCDEVPRIVATE ioctl commands that are
broken in compat mode because the passed structure contains
a pointer.

Change it over to ndo_siocdevprivate for consistency and
make it return an error when called in compat mode. This
could be fixed if there are still users.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/net/appletalk/ipddp.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/drivers/net/appletalk/ipddp.c b/drivers/net/appletalk/ipddp.c
index 51cf5eca9c7f..5566daefbff4 100644
--- a/drivers/net/appletalk/ipddp.c
+++ b/drivers/net/appletalk/ipddp.c
@@ -54,11 +54,12 @@ static netdev_tx_t ipddp_xmit(struct sk_buff *skb,
static int ipddp_create(struct ipddp_route *new_rt);
static int ipddp_delete(struct ipddp_route *rt);
static struct ipddp_route* __ipddp_find_route(struct ipddp_route *rt);
-static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
+static int ipddp_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
+ void __user *data, int cmd);

static const struct net_device_ops ipddp_netdev_ops = {
.ndo_start_xmit = ipddp_xmit,
- .ndo_do_ioctl = ipddp_ioctl,
+ .ndo_siocdevprivate = ipddp_siocdevprivate,
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
};
@@ -268,15 +269,18 @@ static struct ipddp_route* __ipddp_find_route(struct ipddp_route *rt)
return NULL;
}

-static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+static int ipddp_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
+ void __user *data, int cmd)
{
- struct ipddp_route __user *rt = ifr->ifr_data;
struct ipddp_route rcp, rcp2, *rp;

+ if (in_compat_syscall())
+ return -EOPNOTSUPP;
+
if(!capable(CAP_NET_ADMIN))
return -EPERM;

- if(copy_from_user(&rcp, rt, sizeof(rcp)))
+ if (copy_from_user(&rcp, data, sizeof(rcp)))
return -EFAULT;

switch(cmd)
@@ -296,7 +300,7 @@ static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
spin_unlock_bh(&ipddp_route_lock);

if (rp) {
- if (copy_to_user(rt, &rcp2,
+ if (copy_to_user(data, &rcp2,
sizeof(struct ipddp_route)))
return -EFAULT;
return 0;
--
2.29.2