net/tun: handle compat_ioctl directly

The tun driver is the only code in the kernel that operates
on a character device with struct ifreq. Change the driver
to handle the conversion itself so we can contain the
remaining ifreq handling in the socket layer.

This also fixes a bug in the handling of invalid ioctl
numbers on an unbound tun device. The driver treats this
as a TUNSETIFF in native mode, but there is no way for
the generic compat_ioctl() function to emulate this
behaviour. Possibly the driver was only doing this
accidentally anyway, but if any code relies on this
misfeature, it now also works in compat mode.

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

1 files changed, 0 insertions, 20 deletions

diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index f91fd51b32e3..c562e9a4da70 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -539,12 +539,6 @@ static int dev_ifsioc(unsigned int fd, unsigned int cmd, unsigned long arg)
         set_fs (old_fs);
         if (!err) {
                 switch (cmd) {
-                /* TUNSETIFF is defined as _IOW, it should be _IORW
-                 * as the data is copied back to user space, but that
-                 * cannot be fixed without breaking all existing apps.
-                 */
-                case TUNSETIFF:
-                case TUNGETIFF:
                 case SIOCGIFFLAGS:
                 case SIOCGIFMETRIC:
                 case SIOCGIFMTU:
@@ -1979,18 +1973,6 @@ COMPATIBLE_IOCTL(SCSI_IOCTL_SEND_COMMAND)
 COMPATIBLE_IOCTL(SCSI_IOCTL_PROBE_HOST)
 COMPATIBLE_IOCTL(SCSI_IOCTL_GET_PCI)
 #endif
-/* Big T */
-COMPATIBLE_IOCTL(TUNSETNOCSUM)
-COMPATIBLE_IOCTL(TUNSETDEBUG)
-COMPATIBLE_IOCTL(TUNSETPERSIST)
-COMPATIBLE_IOCTL(TUNSETOWNER)
-COMPATIBLE_IOCTL(TUNSETLINK)
-COMPATIBLE_IOCTL(TUNSETGROUP)
-COMPATIBLE_IOCTL(TUNGETFEATURES)
-COMPATIBLE_IOCTL(TUNSETOFFLOAD)
-COMPATIBLE_IOCTL(TUNSETTXFILTER)
-COMPATIBLE_IOCTL(TUNGETSNDBUF)
-COMPATIBLE_IOCTL(TUNSETSNDBUF)
 /* Big V */
 COMPATIBLE_IOCTL(VT_SETMODE)
 COMPATIBLE_IOCTL(VT_GETMODE)
@@ -2571,8 +2553,6 @@ HANDLE_IOCTL(SIOCSIFPFLAGS, dev_ifsioc)
 HANDLE_IOCTL(SIOCGIFPFLAGS, dev_ifsioc)
 HANDLE_IOCTL(SIOCGIFTXQLEN, dev_ifsioc)
 HANDLE_IOCTL(SIOCSIFTXQLEN, dev_ifsioc)
-HANDLE_IOCTL(TUNSETIFF, dev_ifsioc)
-HANDLE_IOCTL(TUNGETIFF, dev_ifsioc)
 HANDLE_IOCTL(SIOCETHTOOL, ethtool_ioctl)
 HANDLE_IOCTL(SIOCBONDENSLAVE, bond_ioctl)
 HANDLE_IOCTL(SIOCBONDRELEASE, bond_ioctl)