ipmi: info leak in compat_ipmi_ioctl()

On x86_64 there is a 4 byte hole between ->recv_type and ->addr.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/ipmi/ipmi_devintf.c

@@ -810,6 +810,7 @@ static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
 		struct ipmi_recv   __user *precv64;
 		struct ipmi_recv   recv64;
 
+		memset(&recv64, 0, sizeof(recv64));
 		if (get_compat_ipmi_recv(&recv64, compat_ptr(arg)))
 			return -EFAULT;