l3mdev_fib_rule_match(9)

✨ l3mdev_fib_rule_match ✨

okay so bestie, this one's a kernel API page — the l3mdev_fib_rule_match(9) manual, no cap 💅 — and it's literally just one little function that answers one little question for you. Let's get into it 🫶

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🌸 NAME 🌸

l3mdev_fib_rule_match — figure out whether a flowi is referencing an L3 master device 👑

Like, that's the whole vibe check. You hand it a flow, it tells you if that flow is pointing at an L3 master device. Iconic, honestly.

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🦋 SYNOPSIS 🦋

int l3mdev_fib_rule_match (struct net *net , struct flowi *fl , struct
fib_lookup_arg *arg );

Three args in, an int out. She's simple, she's efficient, she's serving exactly one purpose 🎀

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💖 ARGUMENTS 💖

• net — the network namespace you want to do your device index lookup in 🌐 that's her whole job here, bestie.
• fl — the flow struct 📨 literally the flow we're asking about, the main character of this whole operation.
• arg — this is where you stash the table that the rule matched with, right here in this struct 🔥 it's giving "output parameter" and we respect it.

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🌈 SEE ALSO 🌈

if you're going down this rabbit hole (and honestly, slay, go off), peep the kernel file ./net/l3mdev/l3mdev.c — that's where the lore lives 📖✨ and also these absolute legends:

• l3mdev_master_ifindex_rcu(9)
• l3mdev_master_upper_ifindex_by_index_rcu(9)
• l3mdev_fib_table_rcu(9)
• l3mdev_link_scope_lookup(9)

fr fr, they all hang out in the same neighborhood 🧚

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mwah 💋 that's the whole page, bestie — no crumbs left behind. This little gem lives out of ./net/l3mdev, and this particular snapshot is dated October 2026 📅 (yes, the future, we're ahead of the game 👑). Go forth and match some fib rules 💜🦋🌸