__fl6_update_dst(9)

💅 __fl6_update_dst(9)

okay so bestie, welcome to the Kernel API Manual — this one lives in section 9, and it's all about updating a flowi destination address with whatever a srcrt option hands you 🎀

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✨ NAME ✨

__fl6_update_dst — update the flowi destination address using the info given by the srcrt option, if there even is one 🦋

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🌸 SYNOPSIS 🌸

struct in6_addr * __fl6_update_dst(struct flowi6 *fl6,
                                   const struct ipv6_txoptions *opt,
                                   struct in6_addr *orig);

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💜 ARGUMENTS 💜

• fl6 — the flowi6 whose daddr is gonna get updated, bestie. that's the whole point of the function, no cap ✨
• opt — a struct ipv6_txoptions that we go digging through looking for the srcrt option 👀
• orig — a copy of the original daddr address, in case it got modified 🫶

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⭐ RETURN ⭐

• Returns NULL if there's no srcrt, or if the srcrt type is invalid 💀
• Otherwise it returns orig, and the initial value of fl6->daddr gets set in orig 💖

literally the whole vibe check is: NULL = nothing happened, orig = we did the thing and stashed the old address in orig 🔥

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👑 SEE ALSO 👑

• Kernel file ./net/ipv6/exthdrs.c
• ipv6_renew_options(9)

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okay that's the whole page, periodt 🌈 and for the cute sign-off: this gem comes to you from the source path ./net/ipv6 and it's dated October 2026 — so go forth and update those destinations, bestie 💅💖🎀