cfg80211_find_ext_elem(9)

📦 version 7.3.1, in nixpkgs unstable

💅 cfg80211_find_ext_elem(9) — ok so this is a kernel API manual page bestie

Hiii so this is cfg80211_find_ext_elem, a kernel function, and honestly she's giving "where's that one specific element" energy and I am obsessed. Stick with me, we're gonna get through this together 🫶

✨ NAME ✨

cfg80211_find_ext_elem — literally the "find the information element with EID Extension in data" girlie. That's the whole job. She looks through your data, she finds the ext element, she slays 💅

✨ SYNOPSIS ✨

const struct element * cfg80211_find_ext_elem (u8 ext_eid , const u8 *ies , int len );

Look at her. Three args, returns a pointer, const-correct, iconic behavior honestly 👑

✨ ARGUMENTS ✨

  • ext_eid — the element ID Extension. This is the specific one you're hunting for, so like, know who you're looking for before you go looking, yk? 🎯
  • ies — the data consisting of IEs. Yes bestie, that's "information elements." This is the pile you're digging through 🧚
  • len — length of the data. Gotta tell her how far she's allowed to go, no cap 🌸

✨ RETURN ✨

So here's the vibe check on what she gives back:

  • NULL if the extended element could not be found 😭
  • NULL if the element is invalid — like, it claims to be longer than the given data, which is a big nope 🙈
  • NULL if the byte array doesn't match 🔥
  • Otherwise? She returns the requested element struct, and we cheer 🎀

✨ NOTE ✨

Heads up bestie: there are no checks on the element length other than having to fit into the given data. That's it. That's the whole safety net. So like, don't go assuming she validated anything else for you, because she did not 💀

ok part 2 is coming, don't go anywhere 🌈

okay so the SEE ALSO on this one is giving ✨phonebook✨ — it's the whole extended friend group and they ALL pulled up to the function's birthday party. every single one of these is a (9) page, so section 9 energy only, and they're all hanging out with the kernel file ./include/net/cfg80211.h. no skipping, bestie, we're naming every last one 🫶

  • Scanning and BSS list handling(9) — the "who's nearby 👀" chapter, iconic
  • struct cfg80211_ssid(9)
  • struct cfg80211_scan_info(9)
  • struct cfg80211_scan_6ghz_params(9)
  • struct cfg80211_scan_request(9)
  • struct cfg80211_match_set(9)
  • struct cfg80211_sched_scan_plan(9)
  • struct cfg80211_bss_select_adjust(9)
  • struct cfg80211_sched_scan_request(9)
  • enum cfg80211_signal_type(9)
  • struct cfg80211_inform_bss(9)
  • struct cfg80211_bss_ies(9)
  • struct cfg80211_bss(9)
  • ieee80211_bss_get_elem(9)
  • ieee80211_bss_get_ie(9)
  • struct cfg80211_auth_request(9)
  • struct cfg80211_assoc_link(9)
  • struct cfg80211_ml_reconf_req(9)
  • enum cfg80211_assoc_req_flags(9)
  • struct cfg80211_assoc_request(9)
  • struct cfg80211_deauth_request(9)
  • struct cfg80211_disassoc_request(9)
  • struct cfg80211_ibss_params(9)
  • struct cfg80211_bss_selection(9)
  • struct cfg80211_connect_params(9)
  • enum cfg80211_connect_params_changed(9)
  • enum wiphy_params_flags(9)
  • struct cfg80211_pmksa(9)
  • struct cfg80211_pkt_pattern(9)
  • struct cfg80211_wowlan_tcp(9)
  • struct cfg80211_wowlan(9)
  • struct cfg80211_coalesce_rules(9)
  • struct cfg80211_coalesce(9)
  • struct cfg80211_wowlan_nd_match(9)
  • struct cfg80211_wowlan_nd_info(9)
  • struct cfg80211_wowlan_wakeup(9)
  • struct cfg80211_gtk_rekey_data(9)
  • struct cfg80211_update_ft_ies_params(9)
  • struct cfg80211_mgmt_tx_params(9)
  • struct cfg80211_dscp_exception(9)
  • struct cfg80211_dscp_range(9)
  • struct cfg80211_qos_map(9)

and that is the entire invite list, bestie, no plus-ones skipped, every (9) accounted for 🔥 keep scrolling, there's more page to go — we are NOT done yet 💜

So the last thing on the menu is the friend-group of other pages 🫶 — every single one of these is a real manual page in this part of the kernel docs, and honestly? It's a whole roll call. Say hi:

🌸 the regulatory girlies

🦋 channel-switch and operating-class besties

🎀 the general-purpose lineup

💅 ext features and the NAN crew, part one

🔥 auth, pmsr, OWE, BSS, and all the colour stuff

🌈 6 GHz, MLO, and channel-checking icons

🧚 more NAN, because she contains multitudes

👑 debugfs, S1G, and the incumbent signal

okay that's literally the whole page, bestie, we ate that 💅 you now know more about cfg80211_find_ext_elem(9) than like 99% of people, no cap. go forth and parse those extension elements 🦋

This little encyclopedia of a page lives at source path ./include/net, and the version/date stamped on it is October 2026 — and the page herself is cfg80211_find_ext_elem(9), iconic as ever. mwah 💖

📦 where this page comes from