newgidmap(1) — Linux manual page


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

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

           Beginning of the range of GIDs inside the user namespace.

           Beginning of the range of GIDs outside the user namespace.

           Length of the ranges (both inside and outside the user

       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

           List of user's subordinate group IDs.

           Mapping of gids from one between user namespaces.

SEE ALSO         top

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

COLOPHON         top

       This page is part of the shadow-utils (utilities for managing
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shadow-utils 4.6                 06/09/2020                     NEWGIDMAP(1)

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