Bug#781602: systemd: Invalid DBus call causes systemd to stop responding to DBus alltogether

[Christian Seiler]

On 03/31/2015 04:44 PM, Michael Biebl wrote:
> Am 31.03.2015 um 15:52 schrieb Christian Seiler:
>> Package: systemd
>> Version: 215-12
>> Severity: normal
>>
>> Dear Maintainers,
>>
>> while I was trying to set a different log level for systemd via DBus, I
>> accidentally forgot that the 'Set' method for DBus properties expects a
>> variant as a data type. So when using the following (wrong) command:
>>
>> dbus-send --print-reply --system --dest=org.freedesktop.systemd1 \
>>      /org/freedesktop/systemd1 org.freedesktop.DBus.Properties.Set \
>>      string:org.freedesktop.systemd1.Manager string:LogLevel \
>>      string:info
>>
>> It won't complete (no answer is given) and systemd stops responding to
>> DBus alltogether (at least on the systemd bus, the private socket is
>> apparently still working, and systemd itself still does things, so it
>> isn't completely crashed).
>>
>> The only thing (besides a reboot) that could make systemd respond to
>> DBus again was
>>
>
> Hm, that's indeed nasty. Have you tried if v219 is affected by this as
> well? If so, it would be worth raising this upstream.

I don't have anything here running Debian experimental, but I still have
a VM with Fedora Rawhide (systemd-219) and there I get the following error:

Error org.freedesktop.DBus.Error.InvalidArgs: Incorrect parameters for 
property 'LogLevel', expected 's', got ''.
(which is what I would have expected, so v219 doesn't appear to be
affected by this bug)

So it appears this is fixed upstream already. Unfortunately, I don't
have time to investigate right now (maybe next week).

Christian