The DIRSEC_BYTENDX(f, i) is supposed to have DIRSEC_NDXMASK(f) in its expansion instead of DIRSEC_NDXMASK(fs). It went unnoticed in the codebase as DIRSEC_BYTENDX(fs, idx) is the way it is used, and it leads to a similar expansion as desired, and thus it has worked till now without any issues from this.
Signed-off-by: Saurav Pal <resyfer.dev@gmail.com>