NEWGIDMAP(1)                    User Commands                   NEWGIDMAP(1)

NAME         top

       newgidmap - set the gid mapping of a user namespace

SYNOPSIS         top

       newgidmap pid gid lowergid count [gid lowergid count [ ... ]]

DESCRIPTION         top

       The newgidmap sets /proc/[pid]/gid_map based on its command line
       arguments and the gids allowed in /etc/subgid. Note that the root
       user is not exempted from the requirement for a valid /etc/subgid
       entry.

       After the pid argument, newgidmap expects sets of 3 integers:

       gid
           Beginning of the range of GIDs inside the user namespace.

       lowergid
           Beginning of the range of GIDs outside the user namespace.

       count
           Length of the ranges (both inside and outside the user
           namespace).

       newgidmap verifies that the caller is the owner of the process
       indicated by pid and that for each of the above sets, each of the
       GIDs in the range [lowergid, lowergid+count] is allowed to the caller
       according to /etc/subgid before setting /proc/[pid]/gid_map.

       Note that newgidmap may be used only once for a given process.

OPTIONS         top

       There currently are no options to the newgidmap command.

FILES         top

       /etc/subgid
           List of user's subordinate group IDs.

       /proc/[pid]/gid_map
           Mapping of gids from one between user namespaces.

SEE ALSO         top

       login.defs(5), newusers(8), subgid(5), useradd(8), userdel(8),
       usermod(8).

COLOPHON         top

       This page is part of the shadow-utils (utilities for managing
       accounts and shadow password files) project.  Information about the
       project can be found at ⟨http://pkg-shadow.alioth.debian.org/⟩.  If
       you have a bug report for this manual page, see
       ⟨http://pkg-shadow.alioth.debian.org/getinvolved.php⟩.  This page was
       obtained from the project's upstream Git repository
       ⟨git://anonscm.debian.org/git/pkg-shadow/shadow.git⟩ on 2018-02-02.
       (At that time, the date of the most recent commit that was found in
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shadow-utils 4.4                 02/02/2018                     NEWGIDMAP(1)

Pages that refer to this page: subgid(5),  subuid(5),  user_namespaces(7)

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