wext: Dispatch and handle compat ioctls entirely in net/wireless/wext.c

Next we can kill the hacks in fs/compat_ioctl.c and also
dispatch compat ioctls down into the driver and 80211 protocol
helper layers in order to handle iw_point objects embedded in
stream replies which need to be translated.

Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 134 insertions, 6 deletions

diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index 97dba0d92348..8ab850bf2eee 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -1757,12 +1757,6 @@ static int do_i2c_smbus_ioctl(unsigned int fd, unsigned int cmd, unsigned long a
         return sys_ioctl(fd, cmd, (unsigned long)tdata);
 }
 
-struct compat_iw_point {
-        compat_caddr_t pointer;
-        __u16 length;
-        __u16 flags;
-};
-
 static int do_wireless_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg)
 {
         struct iwreq __user *iwr;
diff --git a/include/linux/wireless.h b/include/linux/wireless.h
index 4a95a0e5eeca..79d846875825 100644
--- a/include/linux/wireless.h
+++ b/include/linux/wireless.h
@@ -677,6 +677,19 @@ struct	iw_point
   __u16         flags;          /* Optional params */
 };
 
+#ifdef __KERNEL__
+#ifdef CONFIG_COMPAT
+
+#include <linux/compat.h>
+
+struct compat_iw_point {
+        compat_caddr_t pointer;
+        __u16 length;
+        __u16 flags;
+};
+#endif
+#endif
+
 /*
  *      A frequency
  *      For numbers lower than 10^9, we encode the number in 'm' and
diff --git a/include/net/wext.h b/include/net/wext.h
index 80b31d826b7a..6d76a39a9c5b 100644
--- a/include/net/wext.h
+++ b/include/net/wext.h
@@ -12,6 +12,8 @@ extern int wext_proc_init(struct net *net);
 extern void wext_proc_exit(struct net *net);
 extern int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
                              void __user *arg);
+extern int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
+                                    unsigned long arg);
 #else
 static inline int wext_proc_init(struct net *net)
 {
@@ -26,6 +28,11 @@ static inline int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned
 {
         return -EINVAL;
 }
+static inline int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
+                                           unsigned long arg)
+{
+        return -EINVAL;
+}
 #endif
 
 #endif /* __NET_WEXT_H */
diff --git a/net/socket.c b/net/socket.c
index 66c4a8cf6db9..81fe82513046 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -90,6 +90,7 @@
 #include <asm/unistd.h>
 
 #include <net/compat.h>
+#include <net/wext.h>
 
 #include <net/sock.h>
 #include <linux/netfilter.h>
@@ -2210,10 +2211,19 @@ static long compat_sock_ioctl(struct file *file, unsigned cmd,
 {
         struct socket *sock = file->private_data;
         int ret = -ENOIOCTLCMD;
+        struct sock *sk;
+        struct net *net;
+
+        sk = sock->sk;
+        net = sock_net(sk);
 
         if (sock->ops->compat_ioctl)
                 ret = sock->ops->compat_ioctl(sock, cmd, arg);
 
+        if (ret == -ENOIOCTLCMD &&
+            (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST))
+                ret = compat_wext_handle_ioctl(net, cmd, arg);
+
         return ret;
 }
 #endif
diff --git a/net/wireless/wext.c b/net/wireless/wext.c
index 09022cbb58ba..1a4636a9fcde 100644
--- a/net/wireless/wext.c
+++ b/net/wireless/wext.c
@@ -1112,6 +1112,110 @@ int wext_handle_ioctl(struct net *net, struct ifreq *ifr, unsigned int cmd,
         return ret;
 }
 
+#ifdef CONFIG_COMPAT
+static int compat_standard_call(struct net_device       *dev,
+                                struct iwreq            *iwr,
+                                unsigned int            cmd,
+                                iw_handler              handler)
+{
+        const struct iw_ioctl_description *descr;
+        struct compat_iw_point *iwp_compat;
+        struct iw_request_info info;
+        struct iw_point iwp;
+        int err;
+
+        descr = standard_ioctl + (cmd - SIOCIWFIRST);
+
+        if (descr->header_type != IW_HEADER_TYPE_POINT)
+                return ioctl_standard_call(dev, iwr, cmd, handler);
+
+        iwp_compat = (struct compat_iw_point *) &iwr->u.data;
+        iwp.pointer = compat_ptr(iwp_compat->pointer);
+        iwp.length = iwp_compat->length;
+        iwp.flags = iwp_compat->flags;
+
+        info.cmd = cmd;
+        info.flags = 0;
+
+        err = ioctl_standard_iw_point(&iwp, cmd, descr, handler, dev, &info);
+
+        iwp_compat->pointer = ptr_to_compat(iwp.pointer);
+        iwp_compat->length = iwp.length;
+        iwp_compat->flags = iwp.flags;
+
+        return err;
+}
+
+static int compat_private_call(struct net_device *dev, struct iwreq *iwr,
+                               unsigned int cmd, iw_handler handler)
+{
+        const struct iw_priv_args *descr;
+        struct iw_request_info info;
+        int ret, extra_size;
+
+        extra_size = get_priv_descr_and_size(dev, cmd, &descr);
+
+        /* Prepare the call */
+        info.cmd = cmd;
+        info.flags = 0;
+
+        /* Check if we have a pointer to user space data or not. */
+        if (extra_size == 0) {
+                /* No extra arguments. Trivial to handle */
+                ret = handler(dev, &info, &(iwr->u), (char *) &(iwr->u));
+        } else {
+                struct compat_iw_point *iwp_compat;
+                struct iw_point iwp;
+
+                iwp_compat = (struct compat_iw_point *) &iwr->u.data;
+                iwp.pointer = compat_ptr(iwp_compat->pointer);
+                iwp.length = iwp_compat->length;
+                iwp.flags = iwp_compat->flags;
+
+                ret = ioctl_private_iw_point(&iwp, cmd, descr,
+                                             handler, dev, &info, extra_size);
+
+                iwp_compat->pointer = ptr_to_compat(iwp.pointer);
+                iwp_compat->length = iwp.length;
+                iwp_compat->flags = iwp.flags;
+        }
+
+        /* Call commit handler if needed and defined */
+        if (ret == -EIWCOMMIT)
+                ret = call_commit_handler(dev);
+
+        return ret;
+}
+
+int compat_wext_handle_ioctl(struct net *net, unsigned int cmd,
+                             unsigned long arg)
+{
+        void __user *argp = (void __user *)arg;
+        struct iwreq iwr;
+        char *colon;
+        int ret;
+
+        if (copy_from_user(&iwr, argp, sizeof(struct iwreq)))
+                return -EFAULT;
+
+        iwr.ifr_name[IFNAMSIZ-1] = 0;
+        colon = strchr(iwr.ifr_name, ':');
+        if (colon)
+                *colon = 0;
+
+        ret = wext_ioctl_dispatch(net, (struct ifreq *) &iwr, cmd,
+                                  compat_standard_call,
+                                  compat_private_call);
+
+        if (ret >= 0 &&
+            IW_IS_GET(cmd) &&
+            copy_to_user(argp, &iwr, sizeof(struct iwreq)))
+                return -EFAULT;
+
+        return ret;
+}
+#endif
+
 /************************* EVENT PROCESSING *************************/
 /*
  * Process events generated by the wireless layer or the driver.