/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/ is in dahdi-dkms 1:2.10.2~dfsg-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/GpakApi.c
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/GpakApi.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/GpakCust.c
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/GpakCust.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/GpakHpi.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/Kbuild
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/gpakErrs.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/gpakenum.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/voicebus.c
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/voicebus.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/voicebus_net.c
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/voicebus_net.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/vpmadtreg.c
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/vpmadtreg.h
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/vpmoct.c
/usr/src/dahdi-2.10.2~dfsg-1ubuntu1/drivers/dahdi/voicebus/vpmoct.h