core:sandbox: add more /proc/* entries to ProtectKernelTunables=

Make ALSA entries, latency interface, mtrr, apm/acpi, suspend interface,
filesystems configuration and IRQ tuning readonly.

Most of these interfaces now days should be in /sys but they are still
available through /proc, so just protect them. This patch does not touch
/proc/net/...

diff --git a/man/systemd.exec.xml b/man/systemd.exec.xml
index a3a431c82b7d99642c6d527d7d30246f085c5488..f19e7f6ee98ae7262b9a7af236015e61f79ef20a 100644 (file)
--- a/man/systemd.exec.xml
+++ b/man/systemd.exec.xml
@@ -1026,8 +1026,10 @@
         <term><varname>ProtectKernelTunables=</varname></term>
 
         <listitem><para>Takes a boolean argument. If true, kernel variables accessible through
-        <filename>/proc/sys</filename>, <filename>/sys</filename> and <filename>/proc/sysrq-trigger</filename> will be
-        made read-only to all processes of the unit. Usually, tunable kernel variables should only be written at
+        <filename>/proc/sys</filename>, <filename>/sys</filename>, <filename>/proc/sysrq-trigger</filename>,
+        <filename>/proc/latency_stats</filename>, <filename>/proc/acpi</filename>,
+        <filename>/proc/timer_stats</filename>, <filename>/proc/fs</filename> and <filename>/proc/irq</filename> will
+        be made read-only to all processes of the unit. Usually, tunable kernel variables should only be written at
         boot-time, with the <citerefentry><refentrytitle>sysctl.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>
         mechanism. Almost no services need to write to these at runtime; it is hence recommended to turn this on for
         most services. For this setting the same restrictions regarding mount propagation and privileges apply as for

diff --git a/src/core/namespace.c b/src/core/namespace.c
index 8aa8b83c88628219d46a7e1f2063b3649cb7634b..3234fab4bc7a85e4014c0078d4deee9c072522b5 100644 (file)
--- a/src/core/namespace.c
+++ b/src/core/namespace.c
@@ -74,7 +74,18 @@ typedef struct TargetMount {
 static const TargetMount protect_kernel_tunables_table[] = {
         { "/proc/sys",                  READONLY,       false },
         { "/proc/sysrq-trigger",        READONLY,       true  },
+        { "/proc/latency_stats",        READONLY,       true  },
+        { "/proc/mtrr",                 READONLY,       true  },
+        { "/proc/apm",                  READONLY,       true  },
+        { "/proc/acpi",                 READONLY,       true  },
+        { "/proc/timer_stats",          READONLY,       true  },
+        { "/proc/asound",               READONLY,       true  },
+        { "/proc/bus",                  READONLY,       true  },
+        { "/proc/fs",                   READONLY,       true  },
+        { "/proc/irq",                  READONLY,       true  },
         { "/sys",                       READONLY,       false },
+        { "/sys/kernel/debug",          READONLY,       true  },
+        { "/sys/kernel/tracing",        READONLY,       true  },
         { "/sys/fs/cgroup",             READWRITE,      false }, /* READONLY is set by ProtectControlGroups= option */
 };