Arch Linux

Samo____

Member

Registered: 2022-05-04

Posts: 9

SKB with empty ARP packet.

Hello,

I have a kernel module that registers a notifier on a netdevice using:

netdev_rx_handler_register(dev, my_handler, data)

I check each incoming packet, and if ethertype is et to ETH_P_ARP, in print the contents of ARP packet.
It works perfectly fine on my PC and here is the contents of skb->data:

0x0 0x1 0x8 0x0 0x6 0x4 0x0 0x1 0x18 0x31 0xbf 0x9 0xe9 0x56 0xc0 0xa8 0x0 0x67 0x0 0x0 0x0 0x0 0x0 0x0 0xc0 0xa8 0x0 0xd7 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0

However when I do the same on enterprise level server, I still get the SKB with ETH_P_ARP, and

 skb->len 

equal to 42, but the contents of

 skb->data 

is all zeros.

0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 0x0 

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