skb_copy(9)

🌸 NAME 🌸

skb_copy — create private copy of an sk_buff. And yes bestie, this is the skb_copy(9) page from the Kernel API Manual, so buckle up 🫶💅.

✨ SYNOPSIS ✨

struct sk_buff * skb_copy (const struct sk_buff *skb , gfp_t gfp_mask );

🎀 ARGUMENTS 🎀

• skb — buffer to copy. This is the sk_buff you're asking to duplicate, periodt.
• gfp_mask — allocation priority. It's the whole "how hard can we try to get memory" vibe for the copy.

💖 DESCRIPTION 💖

Okay so skb_copy makes a copy of both an sk_buff and its data. This is used when the caller wishes to modify the data and needs a private copy of the data to alter. It returns NULL on failure or the pointer to the buffer on success. The returned buffer has a reference count of 1, no cap.

As a by-product, this function converts non-linear sk_buff to linear one, so that sk_buff becomes completely private and caller is allowed to modify all the data of returned buffer. That's the main-character move here: the returned buffer is fully yours to edit, top to bottom.

Important: this means that this function is not recommended for use in circumstances when only header is going to be modified. Use pskb_copy instead. Like, if you're only touching the header, don't make skb_copy do all that extra work — choose pskb_copy. 💀

🦋 SEE ALSO 🦋

Kernel file: ./net/core/skbuff.c

• drop_reasons_register_subsys(9)
• drop_reasons_unregister_subsys(9)
• skb_panic(9)
• napi_skb_cache_get_bulk(9)
• __build_skb(9)
• build_skb_around(9)
• __napi_build_skb(9)
• napi_build_skb(9)
• __alloc_skb(9)
• __netdev_alloc_skb(9)
• napi_alloc_skb(9)
• skb_pp_cow_data(9)
• skb_pp_frag_ref(9)
• __kfree_skb(9)
• sk_skb_reason_drop(9)
• skb_tx_error(9)
• consume_skb(9)
• __consume_stateless_skb(9)
• napi_consume_skb(9)
• alloc_skb_for_msg(9)
• skb_morph(9)
• skb_copy_ubufs(9)
• skb_clone(9)
• __pskb_copy_fclone(9)
• pskb_expand_head(9)
• skb_expand_head(9)
• skb_copy_expand(9)
• __skb_pad(9)
• pskb_put(9)
• skb_put(9)
• skb_push(9)
• skb_pull(9)
• skb_pull_data(9)
• skb_trim(9)
• __pskb_pull_tail(9)
• skb_copy_bits(9)
• skb_store_bits(9)
• skb_zerocopy(9)
• skb_dequeue(9)
• skb_dequeue_tail(9)
• skb_queue_purge_reason(9)
• skb_rbtree_purge(9)
• skb_queue_head(9)
• skb_queue_tail(9)
• skb_unlink(9)
• skb_append(9)
• skb_split(9)
• skb_shift(9)
• skb_prepare_seq_read(9)
• skb_seq_read(9)
• skb_abort_seq_read(9)
• skb_copy_seq_read(9)
• skb_find_text(9)
• skb_pull_rcsum(9)
• skb_segment(9)
• skb_to_sgvec(9)
• skb_cow_data(9)
• skb_clone_sk(9)
• skb_partial_csum_set(9)
• skb_checksum_setup(9)
• skb_checksum_maybe_trim(9)
• skb_checksum_trimmed(9)
• skb_try_coalesce(9)
• skb_scrub_packet(9)
• skb_eth_pop(9)
• skb_eth_push(9)
• skb_mpls_push(9)
• skb_mpls_pop(9)
• skb_mpls_update_lse(9)
• skb_mpls_dec_ttl(9)
• alloc_skb_with_frags(9)
• skb_condense(9)
• __skb_ext_alloc(9)
• __skb_ext_set(9)
• skb_ext_add(9)
• skb_attempt_defer_free(9)
• skb_splice_from_iter(9)

okay that's the whole page, bestie 💖 signed off with source/version ./net/core and date October 2026, page skb_copy(9) — mwah 💋🎀