Version : LibreELEC 8.2.5
HW : WeTek Play 2
Copy of file >2GB over SMB to external HD attached to Wetek Play USB port fails with following error message (/var/log/log.smbd).
[2018/05/22 19:40:58.453154, 0] ../source3/locking/posix.c:270(posix_fcntl_getlock) posix_fcntl_getlock: WARNING: lock request at offset 2147155976, length 65534 returned an Invalid argument error. This can happen when using 64 bit lock offsets on 32 bit NFS mounted file systems.
External HD file system is EXT4, file copy from PC with Fedora 28
Problem could be solved by adding following line to /storage/.config/samba.conf
strict locking = no
Similar problem described here : hints.macworld.com
Hope it helps fix the problem