maccess: return -ERANGE when probe_kernel_read() fails

long probe_kernel_read(void *dst, const void *src, size_t size)

{

	if (!probe_kernel_read_allowed(src, size))

		return -EFAULT;

		return -ERANGE;

	pagefault_disable();

	probe_kernel_read_loop(dst, src, size, u64, Efault);

	if (unlikely(count <= 0))

		return 0;

	if (!probe_kernel_read_allowed(unsafe_addr, count))

		return -EFAULT;

		return -ERANGE;

	pagefault_disable();

	do {

 * @size: size of the data chunk

 *

 * Safely read from kernel address @src to the buffer at @dst.  If a kernel

 * fault happens, handle that and return -EFAULT.

 * fault happens, handle that and return -EFAULT.  If @src is not a valid kernel

 * address, return -ERANGE.

 *

 * We ensure that the copy_from_user is executed in atomic context so that

 * do_page_fault() doesn't attempt to take mmap_lock.  This makes

	mm_segment_t old_fs = get_fs();

	if (!probe_kernel_read_allowed(src, size))

		return -EFAULT;

		return -ERANGE;

	set_fs(KERNEL_DS);

	pagefault_disable();

 *

 * On success, returns the length of the string INCLUDING the trailing NUL.

 *

 * If access fails, returns -EFAULT (some data may have been copied

 * and the trailing NUL added).

 * If access fails, returns -EFAULT (some data may have been copied and the

 * trailing NUL added).  If @unsafe_addr is not a valid kernel address, return

 * -ERANGE.

 *

 * If @count is smaller than the length of the string, copies @count-1 bytes,

 * sets the last byte of @dst buffer to NUL and returns @count.

	if (unlikely(count <= 0))

		return 0;

	if (!probe_kernel_read_allowed(unsafe_addr, count))

		return -EFAULT;

		return -ERANGE;

	set_fs(KERNEL_DS);

	pagefault_disable();