Provided by: setpriv_2.32-0.1ubuntu2_amd64 bug

NAME

       setpriv - run a program with different Linux privilege settings

SYNOPSIS

       setpriv [options] program [arguments]

DESCRIPTION

       Sets or queries various Linux privilege settings that are inherited across execve(2).

       In comparison to su(1) and runuser(1), setpriv(1) neither uses PAM, nor does it prompt for
       a password.  It is a simple, non-set-user-ID wrapper around execve(2), and can be used  to
       drop  privileges in the same way as setuidgid(8) from daemontools, chpst(8) from runit, or
       similar tools shipped by other service managers.

OPTION

       --clear-groups
              Clear supplementary groups.

       -d, --dump
              Dump current privilege state.  Can be specified  more  than  once  to  show  extra,
              mostly useless, information.  Incompatible with all other options.

       --groups group...
              Set supplementary groups.  The argument is a comma-separated list.

       --inh-caps (+|-)cap...  or  --ambient-caps (+|-)cap...  or  --bounding-set (+|-)cap...
              Set  the  inheritable capabilities, ambient capabilities or the capability bounding
              set.  See capabilities(7).  The argument is a comma-separated list of +cap and -cap
              entries,  which  add  or  remove  an entry respectively. cap can either be a human-
              readable name as seen in capabilities(7) without the cap_ prefix or of  the  format
              cap_N,  where  N is the internal capability index used by Linux.  +all and -all can
              be used to add or remove all caps.  The set  of  capabilities  starts  out  as  the
              current  inheritable set for --inh-caps, the current ambient set for --ambient-caps
              and the current bounding set for --bounding-set.  If you drop  something  from  the
              bounding  set  without also dropping it from the inheritable set, you are likely to
              become confused.  Do not do that.

       --keep-groups
              Preserve supplementary groups.  Only useful in conjunction with --rgid, --egid,  or
              --regid.

       --init-groups
              Initialize  supplementary  groups  using initgroups(3).  Only useful in conjunction
              with --ruid or --reuid.

       --list-caps
              List all known capabilities.  This option must be specified alone.

       --no-new-privs
              Set the no_new_privs bit.   With  this  bit  set,  execve(2)  will  not  grant  new
              privileges.   For  example,  the  set-user-ID and set-group-ID bits as well as file
              capabilities will be disabled.  (Executing binaries with these bits set will  still
              work,  but  they  will not gain privileges.  Certain LSMs, especially AppArmor, may
              result in failures to execute certain programs.)  This bit is  inherited  by  child
              processes  and  cannot  be  unset.   See  prctl(2)  and Documentation/prctl/no_new_
              privs.txt in the Linux kernel source.

              The no_new_privs bit is supported since Linux 3.5.

       --rgid gid, --egid gid, --regid gid
              Set the real, effective, or both GIDs.  The gid argument can be  given  as  textual
              group name.

              For  safety,  you  must  specify one of --clear-groups, --groups, --keep-groups, or
              --init-groups if you set any primary gid.

       --ruid uid, --euid uid, --reuid uid
              Set the real, effective, or both UIDs.  The uid argument can be  given  as  textual
              login name.

              Setting  a  uid  or gid does not change capabilities, although the exec call at the
              end might change capabilities.  This means that, if you are root, you probably want
              to do something like:

                      setpriv --reuid=1000 --regid=1000 --inh-caps=-all

       --securebits (+|-)securebit...
              Set  or  clear  securebits.   The  argument  is  a comma-separated list.  The valid
              securebits are noroot, noroot_locked, no_setuid_fixup, no_setuid_fixup_locked,  and
              keep_caps_locked.  keep_caps is cleared by execve(2) and is therefore not allowed.

       --selinux-label label
              Request a particular SELinux transition (using a transition on exec, not dyntrans).
              This will fail and cause setpriv(1) to abort if SELinux is  not  in  use,  and  the
              transition  may  be  ignored  or  cause  execve(2)  to fail at SELinux's whim.  (In
              particular, this is unlikely to work in conjunction with  no_new_privs.)   This  is
              similar to runcon(1).

       --apparmor-profile profile
              Request a particular AppArmor profile (using a transition on exec).  This will fail
              and cause setpriv(1) to abort if AppArmor is not in use, and the transition may  be
              ignored or cause execve(2) to fail at AppArmor's whim.

       -V, --version
              Display version information and exit.

       -h, --help
              Display help text and exit.

NOTES

       If  applying  any  specified option fails, program will not be run and setpriv will return
       with exit code 127.

       Be careful with this tool -- it may have unexpected security consequences.   For  example,
       setting  no_new_privs  and  then  execing a program that is SELinux-confined (as this tool
       would do) may prevent the SELinux restrictions from taking effect.

EXAMPLE

       If you're looking for behaviour similar to su(1)/runuser(1), or sudo(8)  (without  the  -g
       option), try something like:

           setpriv --reuid=1000 --regid=1000 --init-groups

       If you want to mimic daemontools' setuid(8), try:

           setpriv --reuid=1000 --regid=1000 --clear-groups

SEE ALSO

       runuser(1), su(1), prctl(2), capabilities(7)

AUTHOR

       Andy Lutomirski ⟨luto@amacapital.net

AVAILABILITY

       The  setpriv  command is part of the util-linux package and is available from Linux Kernel
       Archive ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.