ipv6: prevent possible UaF in addrconf_permanent_addr()

These records connect through source-stated identifiers. Shared identifiers or dates alone do not establish shared exposure, root cause or applicability.

CVE-2026-43339 · Microsoft / collected KEV context

cve-program · CVE-2026-43339

• https://git.kernel.org/stable/c/eec49a33611f20336b357b3953df44f1a02049e8
• https://git.kernel.org/stable/c/bacc7f31085c9820922f00bc7d79756ffa13123a
• https://git.kernel.org/stable/c/7bfafa1b0cd582983ebec6bb20f0a435528fe567
• https://git.kernel.org/stable/c/7d9f2f4aabd116ca68fbdab5d8fb8dac74c2ea1e
• https://git.kernel.org/stable/c/25357b670afb5b517096da783abaa5cc4bf8359e
• https://git.kernel.org/stable/c/3cd4efb5df72843dfac892d0b3c7a4a8bd926b65
• https://git.kernel.org/stable/c/2d88ed7fa000e19c2dc0fa31b3a849e3f5bca5c1
• https://git.kernel.org/stable/c/fd63f185979b047fb22a0dfc6bd94d0cab6a6a70

No related operational record is retained in the current change model.