Hello Actually, I'm not sure if it's right to send mail here. I'm testing ipv6ready Self Test 5.0.4 using linux-4.19.118 kernel. ( https://www.ipv6ready.org.cn/home/views/default/resource/logo/phase2-core/index.htm ) Test failed in 82. Part B: Reverse Order Fragments ( Link-Local ) in Section 1. spec In test 82, source transmits 3 fragment packets in reverse order that are originally a icmpv6 packet. There is an overlapping interval between the 2nd and 3rd packet. The test requires the destination MUST drop all packets and respond nothing, but the dest replies Time Exceeded / Reassembly Timeout. I've read some /net/ipv6 codes and think when the kernel receives the 2nd packet ( overlapping occurs ), it drops 3rd and 2nd packets and recognizes the 1st packet as a new fragment packet. ( Is it right ? ) In RFC5722, when a node receives the overlapping fragment, it MUST discard those not yet received. ( In this case, I think it applies to 1st packet ) Please let me know if I misunderstood RFC or if it wasn't implemented in the kernel. Thank you for reading the long article! -- Yugeon Kang -- 강 유 건 사원 펌킨네트웍스㈜ 개발1팀 08380 서울시 구로구 디지털로31길 20 에이스테크노타워 5차 405호 Direct: 070-4263-9937 Mobile: 010-9887-3517 E-mail: yugun819@pumpkinnet.com Tel: 02-863-9380, Fax: 02-2109-6675 www.pumpkinnet.co.kr