[PATCH 3/3] qemu: back up the path in qemuMonitorOpen

[Jiang Jiacheng]

In the case of concurrent VM operations, it is possible to have a null pointer
reference in qemuMonitorOpen. In the case of concurrent VM shutdown, the
priv->monconf will be changed in qemuProcessStop. qemuMonitorOpen releases the
lock before calling qemuMonitorOpenUnix and then references priv->monconf. The
path variable in monconf will cause a null pointer, so it's better to back up the
path content in monconf before releasing the lock.

Signed-off-by: Jiang Jiacheng <jiangjiacheng at huawei.com>
---
 src/qemu/qemu_monitor.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c
index c2808c75a3..792b895570 100644
--- a/src/qemu/qemu_monitor.c
+++ b/src/qemu/qemu_monitor.c
@@ -679,6 +679,7 @@ qemuMonitorOpen(virDomainObj *vm,
 {
     VIR_AUTOCLOSE fd = -1;
     qemuMonitor *ret = NULL;
+    g_aurofree char *path = NULL;
 
     if (config->type != VIR_DOMAIN_CHR_TYPE_UNIX) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -687,8 +688,10 @@ qemuMonitorOpen(virDomainObj *vm,
         return NULL;
     }
 
+    path = g_strdup(config->data.nix.path);
+
     virObjectUnlock(vm);
-    fd = qemuMonitorOpenUnix(config->data.nix.path);
+    fd = qemuMonitorOpenUnix(path);
     virObjectLock(vm);
 
     if (fd < 0)
-- 
2.33.0