How to get the payload of paged data in skb?

I’m trying to implement a netfilter module and in process of debugging TCP packets, I found out that the payload part was missing in skb->data. I believe it might have something to do with the data being paged.

for(int i = 0; i < skb->len; i++) {
    printk(KERN_CONT "%02x\t", skb->data[i]);
}

To present the example I sent "hello world" through the tcp connection, and below is the packet containing this payload, which is last 12 bytes.
skb->data_len = 12
skb->len = 64

Sample packet captured in wireshark:

0000    00 00 00 00 00 00 00 00    00 00 00 00 08 00 45 00
0010    00 40 71 33 40 00 40 06    cb 82 7f 00 00 01 7f 00
0020    00 01 d8 7c 0d 05 c9 1c    57 6f e0 ad a7 51 80 18
0030    02 00 fe 34 00 00 01 01    08 0a 86 63 f5 54 86 62
0040    bb c8 68 65 6c 6c 6f 20    77 6f 72 6c 64 0a

dmesg in hexdump format:

0000    00 00 00 00 00 00 00 00    00 00 00 00 08 00 45 00
0010    00 40 71 33 40 00 40 06    cb 82 7f 00 00 01 7f 00
0020    00 01 d8 7c 0d 05 c9 1c    57 6f e0 ad a7 51 80 18
0030    02 00 fe 34 00 00 01 01    08 0a 86 63 f5 54 86 62
0040    bb c8 00 00 00 00 00 00    00 00 00 00 00 00

Where do i look for the "missing" payload?

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