skb_len_add(9)

💖 skb_len_add(9) — a Kernel API Manual moment 💖

okay so bestie, welcome to skb_len_add(9), straight out of the Kernel API Manual, section 9. this one's a tiny little function with main character energy — it doesn't do a lot, but it does it flawlessly. ✨

---

✨ NAME ✨

skb_len_add — adds a number to len fields of skb 🎀

like, that's it. that's the whole vibe. it adds a number, to the len fields, of an skb. iconic minimalism, no cap.

---

🦋 SYNOPSIS 🦋

void skb_len_add (struct sk_buff *skb , int delta );

it's giving "short and sweet." two arguments, no return value, zero drama. 💅

---

🌸 ARGUMENTS 🌸

• skb — buffer to add len to. this is your sk_buff bestie, the one receiving the whole len situation.
• delta — number of bytes to add. literally the amount of bytes going into those len fields. 🍓

lowkey important: delta is an int, not a size_t, so it's just a plain number of bytes being added — nothing more, nothing less, and the manual doesn't say anything else about it, so we're not gonna invent lore. 🙈

---

🔥 SEE ALSO 🔥

okay this is the part where the page goes absolutely feral — the SEE ALSO section is huge, like it invited the entire networking header file to the group chat. first up, from the kernel file ./include/linux/skbuff.h:

skb checksums(9), skb_frag_size(9), skb_frag_size_set(9), skb_frag_size_add(9), skb_frag_size_sub(9), skb_frag_must_loop(9), skb_frag_foreach_page(9), struct skb_shared_hwtstamps(9), dataref and headerless skbs(9), Basic sk_buff geometry(9), struct sk_buff(9), skb_pfmemalloc(9), skb_dst(9), skb_dstref_steal(9), skb_dstref_restore(9), skb_dst_set(9), skb_dst_set_noref(9), skb_dst_is_noref(9), skb_napi_id(9), skb_unref(9), kfree_skb(9), alloc_skb(9), skb_fclone_busy(9), alloc_skb_fclone(9), skb_pad(9), skb_queue_empty(9), skb_queue_empty_lockless(9), skb_queue_is_last(9), skb_queue_is_first(9), skb_queue_next(9), skb_queue_prev(9), skb_get(9), skb_cloned(9), skb_header_cloned(9), __skb_header_release(9), skb_shared(9), skb_share_check(9), skb_unshare(9), skb_peek(9), __skb_peek(9), skb_peek_next(9), skb_peek_tail(9), skb_queue_len(9), skb_queue_len_lockless(9), __skb_queue_head_init(9), skb_queue_splice(9), skb_queue_splice_init(9), skb_queue_splice_tail(9), skb_queue_splice_tail_init(9), __skb_queue_after(9), __skb_queue_head(9), __skb_queue_tail(9), __skb_dequeue(9), __skb_dequeue_tail(9), __skb_fill_netmem_desc(9), skb_fill_page_desc(9), skb_fill_page_desc_noacc(9), skb_headroom(9), skb_tailroom(9), skb_availroom(9), skb_reserve(9), skb_tailroom_reserve(9), skb_reset_transport_header_careful(9), skb_set_transport_header_careful(9), pskb_trim_unique(9), skb_orphan(9), skb_orphan_frags(9), __skb_queue_purge_reason(9), netdev_alloc_frag(9), netdev_alloc_skb(9), __dev_alloc_pages(9), __dev_alloc_page(9), dev_page_is_reusable(9), skb_propagate_pfmemalloc(9), skb_frag_off(9), skb_frag_off_add(9), skb_frag_off_set(9), skb_frag_off_copy(9), skb_frag_net_iov(9), skb_frag_page(9), skb_frag_netmem(9), skb_frag_address(9), skb_frag_address_safe(9), skb_frag_phys(9), skb_frag_page_copy(9), __skb_frag_dma_map(9), skb_clone_writable(9), skb_cow(9), skb_cow_head(9), skb_padto(9), __skb_put_padto(9), skb_put_padto(9), skb_linearize(9), skb_has_shared_frag(9), skb_linearize_cow(9), skb_postpull_rcsum(9), skb_postpush_rcsum(9), skb_push_rcsum(9), pskb_trim_rcsum(9), skb_needs_linearize(9), skb_get_timestamp(9), skb_data_move(9), skb_postpull_data_move(9), skb_postpush_data_move(9), skb_complete_tx_timestamp(9), skb_tstamp_tx(9), skb_tx_timestamp(9), skb_complete_wifi_ack(9), skb_checksum_complete(9), struct skb_ext(9), skb_checksum_none_assert(9), skb_head_is_locked(9).

like… that's the whole friend group. go read them if you want the full sk_buff cinematic universe. 🌈

---

fr fr though: skb_len_add is just about those len fields. everything else on that list is a different function doing different things — don't mix them up, bestie. 🫶

---

and that's the page!! short king of the kernel API. 💜

✿ sign-off ✿ — this masterpiece lives in ./include/linux and was dated October 2026. go add some len fields, you got this. 🧚⭐😭