Re: [libvirt] [PATCH 3/3] Do proper escaping of cgroup resource partitions
On 04/26/2013 04:45 AM, Daniel P. Berrange wrote:
From: "Daniel P. Berrange" <berrange(a)redhat.com>
If a user cgroup name begins with "cgroup.", "_" or with any of
the controllers from /proc/cgroups followed by a dot, then they
need to be prefixed with a single underscore. eg if there is
an object "cpu.service", then this would end up as "_cpu.service"
in the cgroup filesystem tree, however, "waldo.service" would
stay "waldo.service", at least as long as nobody comes up with
a cgroup controller called "waldo".
Do we also need to consider cgroup names beginning with leading '.'?
Since we require a '.XXXX' suffix on all partitions, there is
no scope for clashing with the kernel 'tasks' and 'release_agent'
files.
Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com>
---
src/util/vircgroup.c | 86 +++++++++++++++++++++++++++++++++++++++++++++++++++
tests/vircgroupmock.c | 27 +++++++++++++---
tests/vircgrouptest.c | 54 ++++++++++++++++++++++++++++++++
3 files changed, 163 insertions(+), 4 deletions(-)
#if defined HAVE_MNTENT_H && defined HAVE_GETMNTENT_R
+static int virCgroupNeedEscape(const char *path)
NeedsEscape sounds a bit better than NeedEscape, if you want to make the
tweak.
+static int virCgroupEscape(char **path)
+{
+ size_t len = strlen(*path);
+ int rc;
+
+ if ((rc = virCgroupNeedEscape(*path)) <= 0)
+ return rc;
+
From here...
+ if (VIR_REALLOC_N(*path, len + 2) < 0)
+ return -ENOMEM;
+
+ memmove((*path) + 1,
+ *path,
+ len + 1);
+ (*path)[0] = '_';
...to here could be simplified to:
char escape = '_';
VIR_INSERT_ELEMENT(*path, 0, len, escape);
+++ b/tests/vircgroupmock.c
@@ -66,7 +66,7 @@ static char *fakesysfsdir;
* Co-mounting cpu & cpuacct controllers
* An anonymous controller for systemd
*/
-const char *mounts =
+const char *procmounts =
I didn't closely inspect the test; but at least the fact that it is
there gives us reassurance that the change is right.
--
Eric Blake eblake redhat com +1-919-301-3266
Libvirt virtualization library http://libvirt.org
Attachments:
- signature.asc (application/pgp-signature — 621 bytes)