/usr/share/live/build/bootloaders/extlinux/ is in open-infrastructure-system-build 20161101-lts2-2.
This file is owned by root:root, with mode 0o755.
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/usr/share/live/build/bootloaders/extlinux/advanced.cfg
/usr/share/live/build/bootloaders/extlinux/extlinux.conf
/usr/share/live/build/bootloaders/extlinux/hdt.c32
/usr/share/live/build/bootloaders/extlinux/install.cfg
/usr/share/live/build/bootloaders/extlinux/ldlinux.c32
/usr/share/live/build/bootloaders/extlinux/libcom32.c32
/usr/share/live/build/bootloaders/extlinux/libgpl.c32
/usr/share/live/build/bootloaders/extlinux/libmenu.c32
/usr/share/live/build/bootloaders/extlinux/libutil.c32
/usr/share/live/build/bootloaders/extlinux/live.cfg.in
/usr/share/live/build/bootloaders/extlinux/menu.cfg
/usr/share/live/build/bootloaders/extlinux/splash.svg
/usr/share/live/build/bootloaders/extlinux/stdmenu.cfg
/usr/share/live/build/bootloaders/extlinux/vesamenu.c32