using sizeof operator

There are instances in the code where sizeof(*ptr) is used. e.g. in net/802/garp.c const struct garp_msg_hdr *gm; if (!pskb_may_pull(skb, sizeof(*gm))) return -1; i want to ask is there any sense in using sizeof(struct garp_msg_hdr) instead of sizeof(*gm) in the above example. Thanks -- Sukrit Sangwan IIT Roorkee