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<title>Auto-loading safe path (Debugging with GDB)</title>

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<a name="Auto_002dloading-safe-path"></a>
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<p>
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<hr>
<a name="Security-restriction-for-auto_002dloading"></a>
<h4 class="subsection">22.8.3 Security restriction for auto-loading</h4>
<a name="index-auto_002dloading-safe_002dpath"></a>

<p>As the files of inferior can come from untrusted source (such as submitted by
an application user) <small>GDB</small> does not always load any files automatically.
<small>GDB</small> provides the &lsquo;<samp>set auto-load safe-path</samp>&rsquo; setting to list
directories trusted for loading files not explicitly requested by user.
Each directory can also be a shell wildcard pattern.
</p>
<p>If the path is not set properly you will see a warning and the file will not
get loaded:
</p>
<div class="smallexample">
<pre class="smallexample">$ ./gdb -q ./gdb
Reading symbols from /home/user/gdb/gdb...
warning: File &quot;/home/user/gdb/gdb-gdb.gdb&quot; auto-loading has been
         declined by your `auto-load safe-path' set
         to &quot;$debugdir:$datadir/auto-load&quot;.
warning: File &quot;/home/user/gdb/gdb-gdb.py&quot; auto-loading has been
         declined by your `auto-load safe-path' set
         to &quot;$debugdir:$datadir/auto-load&quot;.
</pre></div>

<p>To instruct <small>GDB</small> to go ahead and use the init files anyway,
invoke <small>GDB</small> like this:
</p>
<div class="smallexample">
<pre class="smallexample">$ gdb -q -iex &quot;set auto-load safe-path /home/user/gdb&quot; ./gdb
</pre></div>

<p>The list of trusted directories is controlled by the following commands:
</p>
<dl compact="compact">
<dd><a name="set-auto_002dload-safe_002dpath"></a><a name="index-set-auto_002dload-safe_002dpath"></a>
</dd>
<dt><code>set auto-load safe-path <span class="roman">[</span><var>directories</var><span class="roman">]</span></code></dt>
<dd><p>Set the list of directories (and their subdirectories) trusted for automatic
loading and execution of scripts.  You can also enter a specific trusted file.
Each directory can also be a shell wildcard pattern; wildcards do not match
directory separator - see <code>FNM_PATHNAME</code> for system function <code>fnmatch</code>
(see <a href="http://www.gnu.org/software/libc/manual/html_node/Wildcard-Matching.html#Wildcard-Matching">fnmatch</a> in <cite>GNU C Library Reference Manual</cite>).
If you omit <var>directories</var>, &lsquo;<samp>auto-load safe-path</samp>&rsquo; will be reset to
its default value as specified during <small>GDB</small> compilation.
</p>
<p>The list of directories uses path separator (&lsquo;<samp>:</samp>&rsquo; on GNU and Unix
systems, &lsquo;<samp>;</samp>&rsquo; on MS-Windows and MS-DOS) to separate directories, similarly
to the <code>PATH</code> environment variable.
</p>
<a name="show-auto_002dload-safe_002dpath"></a><a name="index-show-auto_002dload-safe_002dpath"></a>
</dd>
<dt><code>show auto-load safe-path</code></dt>
<dd><p>Show the list of directories trusted for automatic loading and execution of
scripts.
</p>
<a name="add_002dauto_002dload_002dsafe_002dpath"></a><a name="index-add_002dauto_002dload_002dsafe_002dpath"></a>
</dd>
<dt><code>add-auto-load-safe-path</code></dt>
<dd><p>Add an entry (or list of entries) to the list of directories trusted for
automatic loading and execution of scripts.  Multiple entries may be delimited
by the host platform path separator in use.
</p></dd>
</dl>

<p>This variable defaults to what <code>--with-auto-load-dir</code> has been configured
to (see <a href="objfile_002dgdbdotext-file.html#with_002dauto_002dload_002ddir">with-auto-load-dir</a>).  <samp>$debugdir</samp> and <samp>$datadir</samp>
substitution applies the same as for <a href="objfile_002dgdbdotext-file.html#set-auto_002dload-scripts_002ddirectory">set auto-load scripts-directory</a>.
The default <code>set auto-load safe-path</code> value can be also overriden by
<small>GDB</small> configuration option <samp>--with-auto-load-safe-path</samp>.
</p>
<p>Setting this variable to <samp>/</samp> disables this security protection,
corresponding <small>GDB</small> configuration option is
<samp>--without-auto-load-safe-path</samp>.
This variable is supposed to be set to the system directories writable by the
system superuser only.  Users can add their source directories in init files in
their home directories (see <a href="Startup.html#Home-Directory-Init-File">Home Directory Init File</a>).  See also deprecated
init file in the current directory
(see <a href="Startup.html#Init-File-in-the-Current-Directory-during-Startup">Init File in the Current Directory during Startup</a>).
</p>
<p>To force <small>GDB</small> to load the files it declined to load in the previous
example, you could use one of the following ways:
</p>
<dl compact="compact">
<dt><samp>~/.gdbinit</samp>: &lsquo;<samp>add-auto-load-safe-path ~/src/gdb</samp>&rsquo;</dt>
<dd><p>Specify this trusted directory (or a file) as additional component of the list.
You have to specify also any existing directories displayed by
by &lsquo;<samp>show auto-load safe-path</samp>&rsquo; (such as &lsquo;<samp>/usr:/bin</samp>&rsquo; in this example).
</p>
</dd>
<dt><kbd>gdb -iex &quot;set auto-load safe-path /usr:/bin:~/src/gdb&quot; &hellip;</kbd></dt>
<dd><p>Specify this directory as in the previous case but just for a single
<small>GDB</small> session.
</p>
</dd>
<dt><kbd>gdb -iex &quot;set auto-load safe-path /&quot; &hellip;</kbd></dt>
<dd><p>Disable auto-loading safety for a single <small>GDB</small> session.
This assumes all the files you debug during this <small>GDB</small> session will come
from trusted sources.
</p>
</dd>
<dt><kbd>./configure --without-auto-load-safe-path</kbd></dt>
<dd><p>During compilation of <small>GDB</small> you may disable any auto-loading safety.
This assumes all the files you will ever debug with this <small>GDB</small> come from
trusted sources.
</p></dd>
</dl>

<p>On the other hand you can also explicitly forbid automatic files loading which
also suppresses any such warning messages:
</p>
<dl compact="compact">
<dt><kbd>gdb -iex &quot;set auto-load no&quot; &hellip;</kbd></dt>
<dd><p>You can use <small>GDB</small> command-line option for a single <small>GDB</small> session.
</p>
</dd>
<dt><samp>~/.gdbinit</samp>: &lsquo;<samp>set auto-load no</samp>&rsquo;</dt>
<dd><p>Disable auto-loading globally for the user
(see <a href="Startup.html#Home-Directory-Init-File">Home Directory Init File</a>).  While it is improbable, you could also
use system init file instead (see <a href="System_002dwide-configuration.html#System_002dwide-configuration">System-wide configuration</a>).
</p></dd>
</dl>

<p>This setting applies to the file names as entered by user.  If no entry matches
<small>GDB</small> tries as a last resort to also resolve all the file names into
their canonical form (typically resolving symbolic links) and compare the
entries again.  <small>GDB</small> already canonicalizes most of the filenames on its
own before starting the comparison so a canonical form of directories is
recommended to be entered.
</p>
<hr>
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