[libvirt] [PATCH] lxc: Bind mount container TTYs

[Richard Weinberger]

On Fri, Jul 3, 2015 at 1:55 PM, Martin Kletzander <mkletzan at redhat.com> wrote:
> On Tue, Jun 23, 2015 at 04:38:57PM +0200, Richard Weinberger wrote:
>>
>> Instead of creating symlinks, bind mount the devices to
>> /dev/pts/XY.
>> Using bind mounts it is no longer needed to add pts devices
>> to files like /dev/securetty.
>>
>> Signed-off-by: Richard Weinberger <richard at nod.at>
>> ---
>> src/lxc/lxc_container.c | 38 +++++++++++++++++++++-----------------
>> 1 file changed, 21 insertions(+), 17 deletions(-)
>>
>
> I spent ridiculously excessive time on this not working for me, but I
> just figured out that simple check whether that file is a symlink or
> not (inside the container) is enough.  Ant it works.
>
> ACK then, sorry for wasting your time with this as well.
>
>
>> diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
>> index 7d531e2..ea76370 100644
>> --- a/src/lxc/lxc_container.c
>> +++ b/src/lxc/lxc_container.c
>> @@ -1141,6 +1141,20 @@ static int
>> lxcContainerMountFSDevPTS(virDomainDefPtr def,
>>     return ret;
>> }
>>
>> +static int lxcContainerBindMountDevice(const char *src, const char *dst)
>> +{
>> +    if (virFileTouch(dst, 0666) < 0)
>> +        return -1;
>> +
>> +    if (mount(src, dst, "none", MS_BIND, NULL) < 0) {
>> +        virReportSystemError(errno, _("Failed to bind %s on to %s"), src,
>> +                             dst);
>> +        return -1;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> static int lxcContainerSetupDevices(char **ttyPaths, size_t nttyPaths)
>> {
>>     size_t i;
>> @@ -1164,34 +1178,24 @@ static int lxcContainerSetupDevices(char
>> **ttyPaths, size_t nttyPaths)
>>     }
>>
>>     /* We have private devpts capability, so bind that */
>> -    if (virFileTouch("/dev/ptmx", 0666) < 0)
>> +    if (lxcContainerBindMountDevice("/dev/pts/ptmx", "/dev/ptmx") < 0)
>>         return -1;
>>
>> -    if (mount("/dev/pts/ptmx", "/dev/ptmx", "ptmx", MS_BIND, NULL) < 0) {
>> -        virReportSystemError(errno, "%s",
>> -                             _("Failed to bind /dev/pts/ptmx on to
>> /dev/ptmx"));
>> -        return -1;
>> -    }
>> -
>>     for (i = 0; i < nttyPaths; i++) {
>>         char *tty;
>>         if (virAsprintf(&tty, "/dev/tty%zu", i+1) < 0)
>>             return -1;
>> -        if (symlink(ttyPaths[i], tty) < 0) {
>> -            virReportSystemError(errno,
>> -                                 _("Failed to symlink %s to %s"),
>> -                                 ttyPaths[i], tty);
>> -            VIR_FREE(tty);
>> +
>> +        if (lxcContainerBindMountDevice(ttyPaths[i], tty) < 0) {
>>             return -1;
>> +            VIR_FREE(tty);
>>         }
>> +
>>         VIR_FREE(tty);
>> +
>>         if (i == 0 &&
>> -            symlink(ttyPaths[i], "/dev/console") < 0) {
>> -            virReportSystemError(errno,
>> -                                 _("Failed to symlink %s to
>> /dev/console"),
>> -                                 ttyPaths[i]);
>> +            lxcContainerBindMountDevice(ttyPaths[i], "/dev/console") < 0)
>>             return -1;
>> -        }
>>     }
>>     return 0;
>> }
>> --
>> 2.4.2
>>
>> --
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>> libvir-list at redhat.com
>> https://www.redhat.com/mailman/listinfo/libvir-list

Ping?

-- 
Thanks,
//richard