lfs-book-zh_CN/chapter05/changingowner.xml

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<sect1 id="ch-tools-changingowner">
  <?dbhtml filename="changingowner.html"?>

  <title>Changing Ownership</title>

  <note>
    <para>The commands in the remainder of this book must be performed while
    logged in as user <systemitem class="username">root</systemitem> and no
    longer as user <systemitem class="username">lfs</systemitem>. Also, double
    check that <envar>$LFS</envar> is set in <systemitem
    class="username">root</systemitem>'s environment.</para>
  </note>

  <para>Currently, the <filename class="directory">$LFS/tools</filename> directory
  is owned by the user <systemitem class="username">lfs</systemitem>, a user
  that exists only on the host system. If the <filename
  class="directory">$LFS/tools</filename> directory is kept as is, the files are
  owned by a user ID without a corresponding account. This is dangerous because
  a user account created later could get this same user ID and would own the
  <filename class="directory">$LFS/tools</filename> directory and all the files
  therein, thus exposing these files to possible malicious manipulation.</para>

  <para>To avoid this issue, you could add the <systemitem
  class="username">lfs</systemitem> user to the new LFS system later when
  creating the <filename>/etc/passwd</filename> file, taking care to assign it
  the same user and group IDs as on the host system. Better yet, change the
  ownership of the <filename class="directory">$LFS/tools</filename> directory to
  user <systemitem class="username">root</systemitem> by running the following
  command:</para>

<screen><userinput>chown -R root:root $LFS/tools</userinput></screen>

  <para>Although the <filename class="directory">$LFS/tools</filename> directory
  can be deleted once the LFS system has been finished, it can be retained to build
  additional LFS systems <emphasis>of the same book version</emphasis>. How best
  to backup <filename class="directory">$LFS/tools</filename> is a matter of
  personal preference.</para>

  <caution>
    <para>If you intend to keep the temporary tools for use in building future LFS
    systems, <emphasis>now</emphasis> is the time to back them up. Subsequent
    commands in chapter 6 will alter the tools currently in place, rendering them
    useless for future builds.</para>
  </caution>

</sect1>