In article https://mail-index.netbsd.org/source-changes/2015/02/08/msg062994.html
Log Message: Correct m_len calculation for m_dup() with mbuf clusters. Fixes kern/49650.
Thank you for fixing problem. My {HEAD,netbsd-7}/{amd64,i386} and netbsd-7/evbarm-earmv6hf for RPI kernel with this patch survive after ping6. -- t-hash