Como montar o sistema de arquivos ufs sob o teste Debian?

Question

Para montar meu /dev/sda4 em /mnt/ufs_mount no Debian Testing, eu tentei os seguintes comandos (funciona bem no Debian Jessie):

modprobe ufs
mount -r -t ufs -o ufstype=ufs2 /dev/sda4 /mnt/ufs_mount

e:

mount -t ufs -o ufstype=ufs2 /dev/sda4 /mnt/ufs_mount

Mas recebo este erro:

mount: /dev/sda4 is write-protected, mounting read-only
mount: wrong fs type, bad option, bad superblock on /dev/sda4,
   missing codepage or helper program, or other error

   In some cases useful info is found in syslog - try
   dmesg | tail or so.

A saída de: dmesg | tail :

[ 1136.965142] ufs: ufs_fill_super(): bad magic number
[ 1255.758946] ufs: ufs_fill_super(): bad magic number
[ 2098.945757] ufs: ufs was compiled with read-only support, can't be mounted as read-write
[ 2098.946045] ufs: You didn't specify the type of your ufs filesystem

      mount -t ufs -o ufstype=sun|sunx86|44bsd|ufs2|5xbsd|old|hp|nextstep|nextstep-cd|openstep ...

      >>>WARNING<<< Wrong ufstype may corrupt your filesystem, default is ufstype=old
[ 2098.967212] ufs: ufs_fill_super(): bad magic number
[ 2927.982112] perf: interrupt took too long (2504 > 2500), lowering kernel.perf_event_max_sample_rate to 79750

Editar Meu sources.list :

deb http://httpredir.debian.org/debian/ stretch main
deb-src http://httpredir.debian.org/debian/ stretch main

deb http://security.debian.org/debian-security stretch/updates main
deb-src http://security.debian.org/debian-security stretch/updates main

e uname -a :

Linux debian 4.6.0-1-amd64 #1 SMP Debian 4.6.4-1 (2016-07-18) x86_64 GNU/Linux

Como montar o sistema de arquivos ufs sob o teste Debian?