Re: [libvirt] [PATCH] qemu: Don't increment jobs counter before DomainObj ref count is incremented

Currently, if domain is being destroyed, it's private data can be freed. If there's however another thread waiting to start a job, it may lead to a NULL dereference and SIGSEGV. Check if reference counter on domain object was successfully incremented. Reported-By: Scott Sullivan <ssullivan(a)liquidweb.com&gt; --- Reported here: https://www.redhat.com/archives/libvir-list/2012-December/msg00931.html src/qemu/qemu_domain.c | 11 +++++++---- 1 files changed, 7 insertions(+), 4 deletions(-) diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 8d8cf02..5cc5bf7 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -764,18 +764,21 @@ qemuDomainObjBeginJobInternal(virQEMUDriverPtr driver, enum qemuDomainJob job, enum qemuDomainAsyncJob asyncJob) { - qemuDomainObjPrivatePtr priv = obj->privateData; + qemuDomainObjPrivatePtr priv; unsigned long long now; unsigned long long then; bool nested = job == QEMU_JOB_ASYNC_NESTED; - priv->jobs_queued++; - if (virTimeMillisNow(&now) < 0) return -1; then = now + QEMU_JOB_WAIT_TIME; - virObjectRef(obj); + if (!virObjectRef(obj)) + return -1;

+ + priv = obj->privateData; + priv->jobs_queued++; +