dpt_i2o: Fix up copy*user

commit ef7562b7 upstream.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/scsi/dpt_i2o.c

@@ -1918,6 +1918,10 @@ static int adpt_i2o_passthru(adpt_hba* pHba, u32 __user *arg)
 		}
 		size = size>>16;
 		size *= 4;
+		if (size > MAX_MESSAGE_SIZE) {
+			rcode = EINVAL;
+			goto cleanup;
+		}
 		/* Copy in the user's I2O command */
 		if (copy_from_user (msg, user_msg, size)) {
 			rcode = -EFAULT;