Input: evdev - fix overflow in compat_ioctl

When exporting input device bitmaps via compat_ioctl on BIG_ENDIAN
platforms evdev calculates data size incorrectly. This causes buffer
overflow if user specifies buffer smaller than maxlen.
Signed-off-by: NKenichi Nagai <kenichi3.nagai@toshiba.co.jp>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/input/evdev.c

@@ -336,7 +336,7 @@ static int bits_to_user(unsigned long *bits, unsigned int maxbit,
 
 	if (compat) {
 		len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t);
-		if (len < maxlen)
+		if (len > maxlen)
 			len = maxlen;
 
 		for (i = 0; i < len / sizeof(compat_long_t); i++)