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>
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c
index db4b7f1..fc9c578 100644
--- a/drivers/net/hamradio/mkiss.c
+++ b/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 @@
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 @@
.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
};