llc_lookup_listener(9)

💖 llc_lookup_listener — a Kernel API Manual moment (section 9, bestie) 💖

okay so picture this: you're deep in the Kernel API Manual, section 9, and you need to know who's listening. That's literally this function. She finds the listener for a local MAC + SAP, and she does it flawlessly. no cap. 🎀

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✨ NAME ✨

llc_lookup_listener — finds the listener for a local MAC + SAP 🦋

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🌸 SYNOPSIS 🌸

struct sock * llc_lookup_listener (struct llc_sap *sap , struct llc_addr
*laddr , const struct net *net );

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💅 ARGUMENTS 💅

• sap — the SAP. that's it, that's the whole description. iconic minimalism honestly 👑
• laddr — the address of the local LLC (that's MAC + SAP, both of them, together, a little duo 🫶)
• net — the netns you wanna look up a socket in 🌈

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🔥 DESCRIPTION 🔥

So what she actually does: she searches the connection list of the SAP and finds the connection that's listening on the local mac and the local sap. very demure, very targeted. 💅

She returns a pointer to the parent socket she found — and NULL otherwise, because sometimes the answer is just no. 😭

⚠️ real talk though: the caller has to make sure local_bh is disabled. this is not a suggestion, bestie, it's a whole requirement. do not skip the vibe check on this one. 💀

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🧚 SEE ALSO 🧚

Kernel file ./net/llc/llc_conn.c — and the whole friend group, fr fr:

• llc_conn_state_process(9)
• llc_conn_rtn_pdu(9)
• llc_conn_resend_i_pdu_as_cmd(9)
• llc_conn_resend_i_pdu_as_rsp(9)
• llc_conn_remove_acked_pdus(9)
• llc_conn_send_pdus(9)
• llc_conn_service(9)
• llc_qualify_conn_ev(9)
• llc_exec_conn_trans_actions(9)
• __llc_lookup_established(9)
• llc_data_accept_state(9)
• llc_find_next_offset(9)
• llc_build_offset_table(9)
• llc_find_offset(9)
• llc_sap_add_socket(9)
• llc_sap_remove_socket(9)
• llc_conn_rcv(9)
• llc_backlog_rcv(9)
• llc_sk_init(9)
• llc_sk_alloc(9)
• llc_sk_free(9)
• llc_sk_reset(9)

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and that's the page!! 🍓 source: ./net/llc, dated October 2026, filed under llc_lookup_listener(9). go forth and look up those listeners, bestie, you've got this 💜✨