namespace: implicitly adds DeviceAllow= when RootImage= is set

RootImage= may require the following settings
```
DeviceAllow=/dev/loop-control rw
DeviceAllow=block-loop rwm
DeviceAllow=block-blkext rwm
```
This adds the following settings implicitly when RootImage= is
specified.

Fixes #9737.
This commit is contained in:
Yu Watanabe 2018-08-06 14:02:28 +09:00
parent fd870bac25
commit fe65e88ba6
2 changed files with 29 additions and 4 deletions

View File

@ -124,7 +124,16 @@
partition table, or a file system within an MBR/MS-DOS or GPT partition table with only a single
Linux-compatible partition, or a set of file systems within a GPT partition table that follows the <ulink
url="https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Discoverable Partitions
Specification</ulink>.</para></listitem>
Specification</ulink>.</para>
<para>When <varname>DevicePolicy=</varname> is set to <literal>closed</literal> or <literal>strict</literal>,
or set to <literal>auto</literal> and <varname>DeviceAllow=</varname> is set, then this setting adds
<filename>/dev/loop-control</filename> with <constant>rw</constant> mode, <literal>block-loop</literal> and
<literal>block-blkext</literal> with <constant>rwm</constant> mode to <varname>DeviceAllow=</varname>. See
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for the details about <varname>DevicePolicy=</varname> or <varname>DeviceAllow=</varname>. Also, see
<varname>PrivateDevices=</varname> below, as it may change the setting of <varname>DevicePolicy=</varname>.
</para></listitem>
</varlistentry>
<varlistentry>

View File

@ -4143,12 +4143,28 @@ int unit_patch_contexts(Unit *u) {
}
cc = unit_get_cgroup_context(u);
if (cc) {
if (cc && ec) {
if (ec &&
ec->private_devices &&
if (ec->private_devices &&
cc->device_policy == CGROUP_AUTO)
cc->device_policy = CGROUP_CLOSED;
if (ec->root_image &&
(cc->device_policy != CGROUP_AUTO || cc->device_allow)) {
/* When RootImage= is specified, the following devices are touched. */
r = cgroup_add_device_allow(cc, "/dev/loop-control", "rw");
if (r < 0)
return r;
r = cgroup_add_device_allow(cc, "block-loop", "rwm");
if (r < 0)
return r;
r = cgroup_add_device_allow(cc, "block-blkext", "rwm");
if (r < 0)
return r;
}
}
return 0;