net, compat_ioctl: handle socket ioctl abuses in tty drivers

Slip and a few other drivers use the same ioctl numbers on
tty devices that are normally meant for sockets. This causes
problems with our compat_ioctl handling that tries to convert
the data structures in a different format.

Fortunately, these five drivers all use 32 bit compatible
data structures in the ioctl numbers, so we can just add
a trivial compat_ioctl conversion function to each of them.

SIOCSIFENCAP and SIOCGIFENCAP do not need to live in
fs/compat_ioctl.c after this any more, and they are not
used on any sockets.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/hamradio/6pack.c

@@ -34,6 +34,7 @@
 #include <linux/ip.h>
 #include <linux/tcp.h>
 #include <linux/semaphore.h>
+#include <linux/compat.h>
 #include <asm/atomic.h>
 
 #define SIXPACK_VERSION    "Revision: 0.3.0"
@@ -777,6 +778,23 @@ static int sixpack_ioctl(struct tty_struct *tty, struct file *file,
 	return err;
 }
 
+#ifdef CONFIG_COMPAT
+static long sixpack_compat_ioctl(struct tty_struct * tty, struct file * file,
+				unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case SIOCGIFNAME:
+	case SIOCGIFENCAP:
+	case SIOCSIFENCAP:
+	case SIOCSIFHWADDR:
+		return sixpack_ioctl(tty, file, cmd,
+				(unsigned long)compat_ptr(arg));
+	}
+
+	return -ENOIOCTLCMD;
+}
+#endif
+
 static struct tty_ldisc_ops sp_ldisc = {
 	.owner		= THIS_MODULE,
 	.magic		= TTY_LDISC_MAGIC,
@@ -784,6 +802,9 @@ static struct tty_ldisc_ops sp_ldisc = {
 	.open		= sixpack_open,
 	.close		= sixpack_close,
 	.ioctl		= sixpack_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= sixpack_compat_ioctl,
+#endif
 	.receive_buf	= sixpack_receive_buf,
 	.write_wakeup	= sixpack_write_wakeup,
 };

drivers/net/hamradio/mkiss.c

@@ -36,6 +36,7 @@
 #include <linux/skbuff.h>
 #include <linux/if_arp.h>
 #include <linux/jiffies.h>
+#include <linux/compat.h>
 
 #include <net/ax25.h>
 
@@ -898,6 +899,23 @@ static int mkiss_ioctl(struct tty_struct *tty, struct file *file,
 	return err;
 }
 
+#ifdef CONFIG_COMPAT
+static long mkiss_compat_ioctl(struct tty_struct *tty, struct file *file,
+	unsigned int cmd, unsigned long arg)
+{
+	switch (arg) {
+	case SIOCGIFNAME:
+	case SIOCGIFENCAP:
+	case SIOCSIFENCAP:
+	case SIOCSIFHWADDR:
+		return mkiss_ioctl(tty, file, cmd,
+				   (unsigned long)compat_ptr(arg));
+	}
+
+	return -ENOIOCTLCMD;
+}
+#endif
+
 /*
  * Handle the 'receiver data ready' interrupt.
  * This function is called by the 'tty_io' module in the kernel when
@@ -972,6 +990,9 @@ static struct tty_ldisc_ops ax_ldisc = {
 	.open		= mkiss_open,
 	.close		= mkiss_close,
 	.ioctl		= mkiss_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= mkiss_compat_ioctl,
+#endif
 	.receive_buf	= mkiss_receive_buf,
 	.write_wakeup	= mkiss_write_wakeup
 };

drivers/net/slip.c

@@ -79,6 +79,7 @@
 #include <linux/rtnetlink.h>
 #include <linux/if_arp.h>
 #include <linux/if_slip.h>
+#include <linux/compat.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include "slip.h"
@@ -1168,6 +1169,27 @@ static int slip_ioctl(struct tty_struct *tty, struct file *file,
 	}
 }
 
+#ifdef CONFIG_COMPAT
+static long slip_compat_ioctl(struct tty_struct *tty, struct file *file,
+					unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case SIOCGIFNAME:
+	case SIOCGIFENCAP:
+	case SIOCSIFENCAP:
+	case SIOCSIFHWADDR:
+	case SIOCSKEEPALIVE:
+	case SIOCGKEEPALIVE:
+	case SIOCSOUTFILL:
+	case SIOCGOUTFILL:
+		return slip_ioctl(tty, file, cmd,
+				  (unsigned long)compat_ptr(arg));
+	}
+
+	return -ENOIOCTLCMD;
+}
+#endif
+
 /* VSV changes start here */
 #ifdef CONFIG_SLIP_SMART
 /* function do_ioctl called from net/core/dev.c
@@ -1260,6 +1282,9 @@ static struct tty_ldisc_ops sl_ldisc = {
 	.close	 	= slip_close,
 	.hangup	 	= slip_hangup,
 	.ioctl		= slip_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= slip_compat_ioctl,
+#endif
 	.receive_buf	= slip_receive_buf,
 	.write_wakeup	= slip_write_wakeup,
 };

drivers/net/wan/x25_asy.c

@@ -33,6 +33,7 @@
 #include <linux/lapb.h>
 #include <linux/init.h>
 #include <linux/rtnetlink.h>
+#include <linux/compat.h>
 #include "x25_asy.h"
 
 #include <net/x25device.h>
@@ -705,6 +706,21 @@ static int x25_asy_ioctl(struct tty_struct *tty, struct file *file,
 	}
 }
 
+#ifdef CONFIG_COMPAT
+static long x25_asy_compat_ioctl(struct tty_struct *tty, struct file *file,
+			 unsigned int cmd,  unsigned long arg)
+{
+	switch (cmd) {
+	case SIOCGIFNAME:
+	case SIOCSIFHWADDR:
+		return x25_asy_ioctl(tty, file, cmd,
+				     (unsigned long)compat_ptr(arg));
+	}
+
+	return -ENOIOCTLCMD;
+}
+#endif
+
 static int x25_asy_open_dev(struct net_device *dev)
 {
 	struct x25_asy *sl = netdev_priv(dev);
@@ -754,6 +770,9 @@ static struct tty_ldisc_ops x25_ldisc = {
 	.open		= x25_asy_open_tty,
 	.close		= x25_asy_close_tty,
 	.ioctl		= x25_asy_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= x25_asy_compat_ioctl,
+#endif
 	.receive_buf	= x25_asy_receive_buf,
 	.write_wakeup	= x25_asy_write_wakeup,
 };

drivers/net/wireless/strip.c

@@ -106,6 +106,7 @@ static const char StripVersion[] = "1.3A-STUART.CHESHIRE";
 #include <linux/serial.h>
 #include <linux/serialP.h>
 #include <linux/rcupdate.h>
+#include <linux/compat.h>
 #include <net/arp.h>
 #include <net/net_namespace.h>
 
@@ -2725,6 +2726,19 @@ static int strip_ioctl(struct tty_struct *tty, struct file *file,
 	return 0;
 }
 
+#ifdef CONFIG_COMPAT
+static long strip_compat_ioctl(struct tty_struct *tty, struct file *file,
+		       unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case SIOCGIFNAME:
+	case SIOCSIFHWADDR:
+		return strip_ioctl(tty, file, cmd,
+			(unsigned long)compat_ptr(arg));
+	}
+	return -ENOIOCTLCMD;
+}
+#endif
 
 /************************************************************************/
 /* Initialization							*/
@@ -2736,6 +2750,9 @@ static struct tty_ldisc_ops strip_ldisc = {
 	.open = strip_open,
 	.close = strip_close,
 	.ioctl = strip_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = strip_compat_ioctl,
+#endif
 	.receive_buf = strip_receive_buf,
 	.write_wakeup = strip_write_some_more,
 };

fs/compat_ioctl.c

@@ -2020,8 +2020,6 @@ COMPATIBLE_IOCTL(FIOGETOWN)
 COMPATIBLE_IOCTL(SIOCGPGRP)
 COMPATIBLE_IOCTL(SIOCATMARK)
 COMPATIBLE_IOCTL(SIOCSIFLINK)
-COMPATIBLE_IOCTL(SIOCSIFENCAP)
-COMPATIBLE_IOCTL(SIOCGIFENCAP)
 COMPATIBLE_IOCTL(SIOCSIFNAME)
 COMPATIBLE_IOCTL(SIOCSARP)
 COMPATIBLE_IOCTL(SIOCGARP)