[libvirt] [PATCH] rpc : fix a access for null pointer

[Peng Hao]

virNetSocketRemoveIOCallback get sock's ObjectLock and will call
virNetSocketEventFree. virNetSocketEventFree may be free sock
object and virNetSocketRemoveIOCallback will access a null pointer
in release sock's ObjectLock.

Signed-off-by: Liu Yun <liu.yunh at zte.com.cn>
Signed-off-by: Peng Hao <peng.hao2 at zte.com.cn>
---
 src/rpc/virnetsocket.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/rpc/virnetsocket.c b/src/rpc/virnetsocket.c
index d228c8a..8b550e8 100644
--- a/src/rpc/virnetsocket.c
+++ b/src/rpc/virnetsocket.c
@@ -2140,14 +2140,12 @@ static void virNetSocketEventFree(void *opaque)
     virFreeCallback ff;
     void *eopaque;
 
-    virObjectLock(sock);
     ff = sock->ff;
     eopaque = sock->opaque;
     sock->func = NULL;
     sock->ff = NULL;
     sock->opaque = NULL;
-    virObjectUnlock(sock);
-
+  
     if (ff)
         ff(eopaque);
 
@@ -2207,6 +2205,7 @@ void virNetSocketUpdateIOCallback(virNetSocketPtr sock,
 
 void virNetSocketRemoveIOCallback(virNetSocketPtr sock)
 {
+    virObjectRef(sock);
     virObjectLock(sock);
 
     if (sock->watch < 0) {
@@ -2220,6 +2219,7 @@ void virNetSocketRemoveIOCallback(virNetSocketPtr sock)
     sock->watch = -1;
 
     virObjectUnlock(sock);
+    virObjectRef(sock);
 }
 
 void virNetSocketClose(virNetSocketPtr sock)
-- 
1.8.3.1