selinux_skb_peerlbl_sid(9)

💖 selinux_skb_peerlbl_sid(9) 💖

okay so this is a page straight out of the Kernel API Manual, bestie — buckle up 🎀

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✨ NAME ✨

selinux_skb_peerlbl_sid — literally the function that figures out the peer label of a packet 🦋

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🌸 SYNOPSIS 🌸

int selinux_skb_peerlbl_sid (struct sk_buff *skb , u16 family , u32 *sid );

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🎀 ARGUMENTS 🎀

• skb — the packet itself, the main character of this whole situation 👑
• family — the protocol family, iykyk
• sid — the packet's peer label SID, the thing we're here to determine 💅

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💜 DESCRIPTION 💜

so what this does is it checks all the various different forms of network peer labeling and determines the peer label/SID for the packet 🫶 and ngl, most of the actual magic happens somewhere else — it's all going down in the security server function security_net_peersid_cmp, not me, I'm just the messenger ✨

the function returns zero if the value in sid is valid (although heads up, it may be SECSID_NULL 💀), or -EACCES if sid is invalid because of inconsistencies with the different peer labels. fr fr, that's the vibe check and sometimes it does not pass 😭

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🦋 SEE ALSO 🦋

Kernel file ./security/selinux/hooks.c, plus the whole friend group:

• selinux_secmark_enabled(9)
• selinux_peerlbl_enabled(9)
• task_avdcache_reset(9)
• task_avdcache_search(9)
• task_avdcache_update(9)
• selinux_inode_permission(9)
• selinux_inode_xattr_skipcap(9)
• selinux_mmap_backing_file(9)
• selinux_conn_sid(9)
• selinux_getselfattr(9)
• selinux_uring_override_creds(9)
• selinux_uring_sqpoll(9)
• selinux_uring_cmd(9)
• selinux_uring_allowed(9)

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and that's the whole page, babe 💖 it lives in ./security/selinux, it's dated October 2026, and honestly? iconic. slay, go read your kernel source, periodt 🧚⭐🌈