floppy: don't write kernel-only members to FDRAWCMD ioctl output

Do not leak kernel-only floppy_raw_cmd structure members to userspace.
This includes the linked-list pointer and the pointer to the allocated
DMA space.

Signed-off-by: Matthew Daley <mattd@bugfuzz.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
static void raw_cmd_done(int flag)
{
	int i;

	if (!flag) {
		raw_cmd->flags |= FD_RAW_FAILURE;
		raw_cmd->flags |= FD_RAW_HARDFAILURE;
	} else {
		raw_cmd->reply_count = inr;
		if (raw_cmd->reply_count > MAX_REPLIES)
			raw_cmd->reply_count = 0;
		for (i = 0; i < raw_cmd->reply_count; i++)
			raw_cmd->reply[i] = reply_buffer[i];

		if (raw_cmd->flags & (FD_RAW_READ | FD_RAW_WRITE)) {
			unsigned long flags;
			flags = claim_dma_lock();
			raw_cmd->length = fd_get_dma_residue();
			release_dma_lock(flags);
		}

		if ((raw_cmd->flags & FD_RAW_SOFTFAILURE) &&
		    (!raw_cmd->reply_count || (raw_cmd->reply[0] & 0xc0)))
			raw_cmd->flags |= FD_RAW_FAILURE;

		if (disk_change(current_drive))
			raw_cmd->flags |= FD_RAW_DISK_CHANGE;
		else
			raw_cmd->flags &= ~FD_RAW_DISK_CHANGE;
		if (raw_cmd->flags & FD_RAW_NO_MOTOR_AFTER)
			motor_off_callback(current_drive);

		if (raw_cmd->next &&
		    (!(raw_cmd->flags & FD_RAW_FAILURE) ||
		     !(raw_cmd->flags & FD_RAW_STOP_IF_FAILURE)) &&
		    ((raw_cmd->flags & FD_RAW_FAILURE) ||
		     !(raw_cmd->flags & FD_RAW_STOP_IF_SUCCESS))) {
			raw_cmd = raw_cmd->next;
			return;
		}
	}
	generic_done(flag);
}

static void raw_cmd_done(int flag)
{
	int i;

	if (!flag) {
		raw_cmd->flags |= FD_RAW_FAILURE;
		raw_cmd->flags |= FD_RAW_HARDFAILURE;
	} else {
		raw_cmd->reply_count = inr;
		if (raw_cmd->reply_count > MAX_REPLIES)
			raw_cmd->reply_count = 0;
		for (i = 0; i < raw_cmd->reply_count; i++)
			raw_cmd->reply[i] = reply_buffer[i];

		if (raw_cmd->flags & (FD_RAW_READ | FD_RAW_WRITE)) {
			unsigned long flags;
			flags = claim_dma_lock();
			raw_cmd->length = fd_get_dma_residue();
			release_dma_lock(flags);
		}

		if ((raw_cmd->flags & FD_RAW_SOFTFAILURE) &&
		    (!raw_cmd->reply_count || (raw_cmd->reply[0] & 0xc0)))
			raw_cmd->flags |= FD_RAW_FAILURE;

		if (disk_change(current_drive))
			raw_cmd->flags |= FD_RAW_DISK_CHANGE;
		else
			raw_cmd->flags &= ~FD_RAW_DISK_CHANGE;
		if (raw_cmd->flags & FD_RAW_NO_MOTOR_AFTER)
			motor_off_callback(current_drive);

		if (raw_cmd->next &&
		    (!(raw_cmd->flags & FD_RAW_FAILURE) ||
		     !(raw_cmd->flags & FD_RAW_STOP_IF_FAILURE)) &&
		    ((raw_cmd->flags & FD_RAW_FAILURE) ||
		     !(raw_cmd->flags & FD_RAW_STOP_IF_SUCCESS))) {
			raw_cmd = raw_cmd->next;
			return;
		}
	}
	generic_done(flag);
}
