Re: [libvirt] [PATCH 2/2] rpc: Fix segmentation fault when no worker pool is available

On Fri, Jun 15, 2018 at 01:39 PM +0200, Marc Hartmayer <mhartmay(a)linux.ibm.com&gt; wrote: > If srv->workers is a NULL pointer, as it is the case if there are no > workers, then don't try to dereference it. > > Signed-off-by: Marc Hartmayer <mhartmay(a)linux.ibm.com&gt; > Reviewed-by: Boris Fiuczynski <fiuczy(a)linux.ibm.com&gt; > --- > src/rpc/virnetserver.c | 22 +++++++++++++++------- > 1 file changed, 15 insertions(+), 7 deletions(-) > > diff --git a/src/rpc/virnetserver.c b/src/rpc/virnetserver.c > index 5ae809e372..be6f610880 100644 > --- a/src/rpc/virnetserver.c > +++ b/src/rpc/virnetserver.c > @@ -933,13 +933,21 @@ virNetServerGetThreadPoolParameters(virNetServerPtr srv, > size_t *jobQueueDepth) > { > virObjectLock(srv); > - > - *minWorkers = virThreadPoolGetMinWorkers(srv->workers); > - *maxWorkers = virThreadPoolGetMaxWorkers(srv->workers); > - *freeWorkers = virThreadPoolGetFreeWorkers(srv->workers); > - *nWorkers = virThreadPoolGetCurrentWorkers(srv->workers); > - *nPrioWorkers = virThreadPoolGetPriorityWorkers(srv->workers); > - *jobQueueDepth = virThreadPoolGetJobQueueDepth(srv->workers); > + if (srv->workers) { > + *minWorkers = virThreadPoolGetMinWorkers(srv->workers); > + *maxWorkers = virThreadPoolGetMaxWorkers(srv->workers); > + *freeWorkers = virThreadPoolGetFreeWorkers(srv->workers); > + *nWorkers = virThreadPoolGetCurrentWorkers(srv->workers); > + *nPrioWorkers = virThreadPoolGetPriorityWorkers(srv->workers); > + *jobQueueDepth = virThreadPoolGetJobQueueDepth(srv->workers); > + } else { > + *minWorkers = 0; > + *maxWorkers = 0; > + *freeWorkers = 0; > + *nWorkers = 0; > + *nPrioWorkers = 0; > + *jobQueueDepth = 0; > + } > > virObjectUnlock(srv); > return 0; > -- > 2.13.6 After thinking again it probably makes more sense (and the code more beautiful) to initialize the worker pool even for maxworker=0 (within

virNetServerNew) (=> we'll have to adapt virNetServerDispatchNewMessage as well). BTW, there is also a segmentation fault in virThreadPoolSetParameters… And currently it’s not possible to start with maxworkers set to 0 and then increase it via