[libvirt] [PATCH] qemu_migration: Avoid writing to freed memory

[Jiri Denemark]

When a domain is killed on the source host while it is being migrated
and libvirtd is waiting for the migration to finish (waiting for the
domain condition in qemuMigrationSrcWaitForCompletion), the run-time
state including priv->job.current may already be freed once
virDomainObjWait returns with -1. Thus the priv->job.current pointer
cached in jobInfo is no longer valid and setting jobInfo->status may
crash the daemon.

https://bugzilla.redhat.com/show_bug.cgi?id=1593137

Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
---
 src/qemu/qemu_migration.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
index 435cd174af..825a9d399b 100644
--- a/src/qemu/qemu_migration.c
+++ b/src/qemu/qemu_migration.c
@@ -1584,7 +1584,8 @@ qemuMigrationSrcWaitForCompletion(virQEMUDriverPtr driver,
 
         if (events) {
             if (virDomainObjWait(vm) < 0) {
-                jobInfo->status = QEMU_DOMAIN_JOB_STATUS_FAILED;
+                if (virDomainObjIsActive(vm))
+                    jobInfo->status = QEMU_DOMAIN_JOB_STATUS_FAILED;
                 return -2;
             }
         } else {
-- 
2.18.0