<listitem><para>Controls the CPU
affinity of the executed
processes. Takes a space-separated
- list of CPU indexes. This option may
+ list of CPU indices. This option may
be specified more than once in which
case the specificed CPU affinity masks
are merged. If the empty string is
<varlistentry>
<term><varname>StandardError=</varname></term>
<listitem><para>Controls where file
- descriptor 2 (STDERR) of the executed
- processes is connected to. The
- available options are identical to
+ descriptor 2 (standard error) of the
+ executed processes is connected to.
+ The available options are identical to
those of
<varname>StandardOutput=</varname>,
with one exception: if set to
<varlistentry>
<term><varname>TTYPath=</varname></term>
<listitem><para>Sets the terminal
- device node to use if standard input,
- output or stderr are connected to a
+ device node to use if standard input, output,
+ or error are connected to a
TTY (see above). Defaults to
<filename>/dev/console</filename>.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>SELinuxContext=</varname></term>
- <listitem><para>Set the SELinux context of the
- executed process. If set, this will override the
- automated domain transition. However, the policy
- still need to autorize the transition. See
+ <listitem><para>Set the SELinux
+ security context of the executed
+ process. If set, this will override
+ the automated domain
+ transition. However, the policy still
+ needs to autorize the transition. This
+ directive is ignored if SELinux is
+ disabled. If prefixed by
+ <literal>-</literal>, all errors will
+ be ignored. See
<citerefentry><refentrytitle>setexeccon</refentrytitle><manvolnum>3</manvolnum></citerefentry>
for details.</para></listitem>
</varlistentry>
list of system call
names. If this setting is used, all
system calls executed by the unit
- process except for the listed ones
+ processes except for the listed ones
will result in immediate process
termination with the
<constant>SIGSYS</constant> signal
merged. If the empty string is
assigned, the filter is reset, all
prior assignments will have no
- effect.</para></listitem>
+ effect.</para>
+
+ <para>If you specify both types of
+ this option (i.e. whitelisting and
+ blacklisting), the first encountered
+ will take precedence and will dictate
+ the default action (termination or
+ approval of a system call). Then the
+ next occurrences of this option will
+ add or delete the listed system calls
+ from the set of the filtered system
+ calls, depending of its type and the
+ default action. (For example, if you have started
+ with a whitelisting of
+ <function>read</function> and
+ <function>write</function>, and right
+ after it add a blacklisting of
+ <function>write</function>, then
+ <function>write</function> will be
+ removed from the set.)
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>SystemCallErrorNumber=</varname></term>
+
+ <listitem><para>Takes an
+ <literal>errno</literal> error number
+ name to return when the system call
+ filter configured with
+ <varname>SystemCallFilter=</varname>
+ is triggered, instead of terminating
+ the process immediately. Takes an
+ error name such as
+ <literal>EPERM</literal>,
+ <literal>EACCES</literal> or
+ <literal>EUCLEAN</literal>. When this
+ setting is not used, or when the empty
+ string is assigned, the process will be
+ terminated immediately when the filter
+ is triggered.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>SystemCallArchitectures=</varname></term>
+
+ <listitem><para>Takes a space
+ separated list of architecture
+ identifiers to include in the system
+ call filter. The known architecture
+ identifiers are
+ <literal>x86</literal>,
+ <literal>x86-64</literal>,
+ <literal>x32</literal>,
+ <literal>arm</literal> as well as the
+ special identifier
+ <literal>native</literal>. Only system
+ calls of the specified architectures
+ will be permitted to processes of this
+ unit. This is an effective way to
+ disable compatibility with non-native
+ architectures for processes, for
+ example to prohibit execution of
+ 32-bit x86 binaries on 64-bit x86-64
+ systems. The special
+ <literal>native</literal> identifier
+ implicitly maps to the native
+ architecture of the system (or more
+ strictly: to the architecture the
+ system manager is compiled for). Note
+ that setting this option to a
+ non-empty list implies that
+ <literal>native</literal> is included
+ too. By default, this option is set to
+ the empty list, i.e. no architecture
+ system call filtering is
+ applied.</para></listitem>
</varlistentry>
</variablelist>
~ianmdlvl / elogind.git / blobdiff