[libvirt] [PATCH v3 10/12] LXC: controller: change the owner of devices created on host

[Richard RW. Weinberger]

Hi!

----- Ursprüngliche Mail -----
> Since these devices are created for the container.
> the owner should be the root user of the container.
> 
> Signed-off-by: Gao feng <gaofeng at cn.fujitsu.com>
> ---
>  src/lxc/lxc_controller.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/src/lxc/lxc_controller.c b/src/lxc/lxc_controller.c
> index f892ce3..b2ace20 100644
> --- a/src/lxc/lxc_controller.c
> +++ b/src/lxc/lxc_controller.c
> @@ -1260,6 +1260,8 @@ static int
> virLXCControllerPopulateDevices(virLXCControllerPtr ctrl)
>      size_t i;
>      int ret = -1;
>      char *path = NULL;
> +    uid_t uid = (uid_t)-1;
> +    gid_t gid = (gid_t)-1;
>      const struct {
>          int maj;
>          int min;
> @@ -1276,6 +1278,11 @@ static int
> virLXCControllerPopulateDevices(virLXCControllerPtr ctrl)
>      if (virLXCControllerSetupDev(ctrl) < 0)
>          goto out;
>  
> +    if (ctrl->def->idmap.uidmap) {
> +        uid = ctrl->def->idmap.uidmap[0].target;
> +        gid = ctrl->def->idmap.gidmap[0].target;
> +    }
> +
>      /* Populate /dev/ with a few important bits */
>      for (i = 0 ; i < ARRAY_CARDINALITY(devs) ; i++) {
>          if (virAsprintf(&path, "/%s/%s.dev/%s",
> @@ -1293,6 +1300,13 @@ static int
> virLXCControllerPopulateDevices(virLXCControllerPtr ctrl)
>                                   devs[i].path);
>              goto out;
>          }
> +
> +        if (chown(path, uid, gid) < 0) {
> +            virReportSystemError(errno,
> +                                 _("Failed to change owner of %s to
> %u:%u"),
> +                                 devs[i].path, uid, gid);
> +            goto out;
> +        }
>          VIR_FREE(path);

This looks suspicious.
If you free path in the exit path you end up with a double free.
If not you may leak memory if chown() fails.

>      }

Thanks,
//richard