vlan_insert_inner_tag(9)

📦 version 7.3.1, in nixpkgs unstable

💅 vlan_insert_inner_tag(9) — inner VLAN tag inserting 💅

okay so bestie, welcome to the Kernel API Manual corner of the group chat 🫶 this page is literally about inner VLAN tag inserting, and it’s lowkey iconic. Let’s unpack it, no cap.

🌸 NAME 🌸

vlan_insert_inner_tag — inner VLAN tag inserting. That’s the whole name, periodt.

✨ SYNOPSIS ✨

struct sk_buff * vlan_insert_inner_tag (struct sk_buff *skb , __be16
vlan_proto , u16 vlan_tci , unsigned int mac_len );

🎀 ARGUMENTS 🎀

  • skb — the skbuff to tag, bestie.
  • vlan_proto — VLAN encapsulation protocol.
  • vlan_tci — VLAN TCI to insert.
  • mac_len — MAC header length including outer vlan headers.

🦋 DESCRIPTION 🦋

okay so what it does: it inserts the VLAN tag into skb as part of the payload at offset mac_len, and it returns a VLAN tagged skb. Heads up: this might change skb->head — so don’t get too attached to that pointer, bestie 😭.

Following the skb_unshare example, if there’s an error, the calling function does not have to worry about freeing the original skb. That’s the self-care we deserve 💅.

It does not change skb->protocol, so this function can be used during receive. Slay.

👑 RETURN 👑

  • On success: modified skb ✨
  • On error: NULL (and skb is freed) 💀

🌈 SEE ALSO 🌈

the kernel file is right here: ./include/linux/if_vlan.h. And these related pages are all in the group chat too:

okay that’s the whole page, bestie 🫶 this was vlan_insert_inner_tag(9) from the Kernel API Manual, sourced from ./include/linux, dated October 2026. mwah 💋

📦 where this page comes from