centos man page for skb_pull_rcsum

SKB_PULL_RCSUM(9)						 Linux Networking						 SKB_PULL_RCSUM(9)

NAME
       skb_pull_rcsum - pull skb and update receive checksum

SYNOPSIS
       unsigned char * skb_pull_rcsum(struct sk_buff * skb, unsigned int len);

ARGUMENTS
       skb
	   buffer to update

       len
	   length of data pulled

DESCRIPTION
       This function performs an skb_pull on the packet and updates the CHECKSUM_COMPLETE checksum. It should be used on receive path processing
       instead of skb_pull unless you know that the checksum difference is zero (e.g., a valid IP header) or you are setting ip_summed to
       CHECKSUM_NONE.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							 SKB_PULL_RCSUM(9)