The ornamental design for sock and fastening means, as shown and described.
FIG. 1 is a front elevational view of a sock and fastening means showing our new design, the undisclosed rear is not part of the claimed design; and,
FIG. 2 is an enlarged view of a portion of sock and fastening means showing the soc loc male and female snaps on the label of a pair of socks for purposes of illustration.