/usr/src/zfs-0.6.5.6/lib/libspl/ is in zfs-dkms 0.6.5.6-0ubuntu8.
This file is owned by root:root, with mode 0o755.
..
/usr/src/zfs-0.6.5.6/lib/libspl/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/asm-generic/
/usr/src/zfs-0.6.5.6/lib/libspl/asm-generic/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/asm-i386/
/usr/src/zfs-0.6.5.6/lib/libspl/asm-i386/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/asm-x86_64/
/usr/src/zfs-0.6.5.6/lib/libspl/asm-x86_64/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/
/usr/src/zfs-0.6.5.6/lib/libspl/include/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/ia32/
/usr/src/zfs-0.6.5.6/lib/libspl/include/ia32/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/ia32/sys/
/usr/src/zfs-0.6.5.6/lib/libspl/include/ia32/sys/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/rpc/
/usr/src/zfs-0.6.5.6/lib/libspl/include/rpc/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/sys/
/usr/src/zfs-0.6.5.6/lib/libspl/include/sys/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/sys/dktp/
/usr/src/zfs-0.6.5.6/lib/libspl/include/sys/dktp/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/sys/sysevent/
/usr/src/zfs-0.6.5.6/lib/libspl/include/sys/sysevent/Makefile.in
/usr/src/zfs-0.6.5.6/lib/libspl/include/util/
/usr/src/zfs-0.6.5.6/lib/libspl/include/util/Makefile.in