[libvirt] [PATCH] daemon: Fix domain name leak in error path

[John Ferlan]

On 04/13/2017 06:44 AM, Wang King wrote:
> domain name duplicated in make_nonnull_domain, but not freed when virTypedParamsSerialize return negative.
> ---
>  daemon/remote.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/daemon/remote.c b/daemon/remote.c
> index 1610fea..edee981 100644
> --- a/daemon/remote.c
> +++ b/daemon/remote.c
> @@ -1066,8 +1066,10 @@ remoteRelayDomainEventTunable(virConnectPtr conn,
>      if (virTypedParamsSerialize(params, nparams,
>                                  (virTypedParameterRemotePtr *) &data.params.params_val,
>                                  &data.params.params_len,
> -                                VIR_TYPED_PARAM_STRING_OKAY) < 0)
> +                                VIR_TYPED_PARAM_STRING_OKAY) < 0) {
> +        VIR_FREE(data.dom.name);
>          return -1;
> +    }

While true this does "fix" this instance, it also doesn't seem to be the
only instance [1] of this and isn't handled via "normal" error path
using virObjectUnref(dom); [2]

[1] example of another instance w/ similar code/leak/issue
See also remoteRelayDomainEventJobCompleted

I'll assume this one borrowed from remoteRelayDomainEventTunable
considering which came first.

[2] example of another instance w/ similar code, but no leak
See also remoteDispatchConnectGetAllDomainStats

FWIW: The sequence I used to search on is:

make_nonnull_domain
virTypedParamsSerialize


While looking through the code during review, I noticed a couple of
other possible cleanups. So, if you're feeling adventurous, there's also
two instances where a VIR_STRDUP error is followed by a goto error where
all the error label does is VIR_FREE the address that failed the
VIR_STRDUP and there's no other way to get to the error label... See:

remoteRelayDomainEventBlockJob2
remoteRelayDomainEventBlockJob

It would seem those two could just have a return -1 instead to follow
other similar such error paths:

remoteRelayDomainEventDeviceRemovalFailed
remoteRelayDomainEventDeviceAdded
remoteRelayDomainEventDeviceRemoved
remoteRelayDomainEventTrayChange


John
>  
>      remoteDispatchObjectEventSend(callback->client, remoteProgram,
>                                    REMOTE_PROC_DOMAIN_EVENT_CALLBACK_TUNABLE,
>