Ubuntu under Windows 10 Linux Subsystem

I tried to find out why capsh is failing to set securebits, but no success. Anyway, that error is same when capsh is run by a non superuser.

As workaround you can:

1. Modify that script to use bash instead in /usr/lib/libdvd-pkg/b-i_libdvdcss.sh which is called by postinst. Change this line:

   CAPSH="$(which capsh) --secbits=0x14 --drop=cap_dac_read_search,cap_fsetid,cap_kill,cap_setgid,cap_setuid,cap_setpcap,cap_linux_immutable,cap_net_bind_service,cap_net_broadcast,cap_net_admin,cap_net_raw,cap_ipc_lock,cap_ipc_owner,cap_sys_module,cap_sys_rawio,cap_sys_chroot,cap_sys_ptrace,cap_sys_pacct,cap_sys_admin,cap_sys_boot,cap_sys_nice,cap_sys_resource,cap_sys_time,cap_sys_tty_config,cap_mknod,cap_lease,cap_audit_write,cap_audit_control,cap_setfcap,cap_mac_override,cap_mac_admin,cap_syslog-ep --print --" || CAPSH=/bin/bash
   

   to:

   CAPSH=/bin/bash
   

2. Then fix APT

   sudo apt install -f
   

I read also it work fine with WSL2 (which a VM). Bug Report: github.com/microsoft/WSL/issues/4278