smk_write_ambient(9)

💅 smk_write_ambient — like, the whole vibe

okay so bestie, welcome to smk_write_ambient(9) from the Kernel API Manual, section 9 🎀 this is the little kernel function that handles write() for /smack/ambient, and yes it's as niche and iconic as it sounds. iykyk.

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✨ NAME ✨

smk_write_ambient — literally the write() handler for /smack/ambient. that's the whole job. main character energy, honestly 💅

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🌸 SYNOPSIS 🌸

ssize_t smk_write_ambient (struct file *file , const char __user *buf ,
       size_t count , loff_t *ppos );

look at her. four params, one ssize_t return, zero apology 🫶

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🦋 ARGUMENTS 🦋

• file — the file pointer. plot twist: it's not actually used 🙈 she's just there for the vibes (and the signature).
• buf — where to get the data from. this is the source of truth, the origin story, the payload 💖
• count — bytes sent. how many of them there are.
• ppos — where to start. the starting point. the beginning of the era ✨

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🔥 DESCRIPTION 🔥

Returns the number of bytes written, or an error code, as appropriate. that's it, that's the whole behaviour, and she ate 💀👑

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💜 SEE ALSO 💜

okay this is the part where the whole friend group shows up, and they ALL came 🎉 no one got left on read:

Kernel file ./security/smack/smackfs.c

smk_netlabel_audit_set(9), smk_set_access(9), smk_perm_from_str(9), smk_fill_rule(9), smk_parse_rule(9), smk_parse_long_rule(9), smk_write_rules_list(9), smk_open_load(9), smk_write_load(9), smk_cipso_doi(9), smk_unlbl_ambient(9), smk_open_cipso(9), smk_set_cipso(9), smk_write_cipso(9), smk_open_cipso2(9), smk_write_cipso2(9), smk_open_net4addr(9), smk_net4addr_insert(9), smk_write_net4addr(9), smk_open_net6addr(9), smk_net6addr_insert(9), smk_write_net6addr(9), smk_read_doi(9), smk_write_doi(9), smk_read_cipso_auto_level(9), smk_write_cipso_auto_level(9), smk_read_ambient(9), smk_list_swap_rcu(9), smk_parse_label_list(9), smk_destroy_label_list(9), smk_write_onlycap(9), smk_read_unconfined(9), smk_write_unconfined(9), smk_read_logging(9), smk_write_logging(9), smk_open_load_self(9), smk_write_load_self(9), smk_user_access(9), smk_write_access(9), smk_open_load2(9), smk_write_load2(9), smk_open_load_self2(9), smk_write_load_self2(9), smk_write_access2(9), smk_write_revoke_subj(9), smk_init_sysfs(9), smk_write_change_rule(9), smk_read_syslog(9), smk_write_syslog(9), smk_open_relabel_self(9), smk_write_relabel_self(9), smk_read_ptrace(9), smk_write_ptrace(9), smk_fill_super(9), smk_get_tree(9), smk_init_fs_context(9), init_smk_fs(9)

periodt. that's the whole squad 🌈⭐

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lowkey a reminder before you go: file really is not used, so don't come for her about it bestie 🧚

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and that's a wrap, bestie 💖 this lil page lives in ./security/smack, dated October 2026, and it's your girl smk_write_ambient(9) signing off — mwah, go read the source, it's giving slay 🌸👑