newuidmap(1) — Linux manual page


NEWUIDMAP(1)                    User Commands                   NEWUIDMAP(1)

NAME         top

       newuidmap - set the uid mapping of a user namespace

SYNOPSIS         top

       newuidmap pid uid loweruid count [uid loweruid count [ ... ]]

DESCRIPTION         top

       The newuidmap sets /proc/[pid]/uid_map based on its command line
       arguments and the uids allowed in /etc/subuid. Note that the root
       user is not exempted from the requirement for a valid /etc/subuid

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

           Beginning of the range of UIDs inside the user namespace.

           Beginning of the range of UIDs outside the user namespace.

           Length of the ranges (both inside and outside the user

       newuidmap verifies that the caller is the owner of the process
       indicated by pid and that for each of the above sets, each of the
       UIDs in the range [loweruid, loweruid+count) is allowed to the caller
       according to /etc/subuid before setting /proc/[pid]/uid_map.

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

OPTIONS         top

       There currently are no options to the newuidmap command.

FILES         top

           List of user's subordinate user IDs.

           Mapping of uids from one between user namespaces.

SEE ALSO         top

       login.defs(5), newusers(8), subuid(5), useradd(8), usermod(8),

COLOPHON         top

       This page is part of the shadow-utils (utilities for managing
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       ⟨⟩ on 2020-11-01.  (At that
       time, the date of the most recent commit that was found in the repos‐
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shadow-utils 4.8.1               11/01/2020                     NEWUIDMAP(1)

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