[libvirt] [PATCH] storage: fix crash caused by no check return before set close

[Luyao Huang]

https://bugzilla.redhat.com/show_bug.cgi?id=1087104#c5

When try to use a invalid offset do volupload, libvirt will
get failed in virFDStreamOpenFileInternal, but seems libvirt do not
check the return in storageVolUpload, and call virFDStreamSetInternalCloseCb
, but stream doesn't have a privateData (is NULL), then crash.
Although libvirt have a check for invalid offset in cmdVolUpload, but i think
there should have some other way to touch off this crash.

0  0x00007f09429a9c10 in pthread_mutex_lock () from /lib64/libpthread.so.0
1  0x00007f094514dbf5 in virMutexLock (m=<optimized out>) at util/virthread.c:88
2  0x00007f09451cb211 in virFDStreamSetInternalCloseCb at fdstream.c:795
3  0x00007f092ff2c9eb in storageVolUpload at storage/storage_driver.c:2098
4  0x00007f09451f46e0 in virStorageVolUpload at libvirt.c:14000
5  0x00007f0945c78fa1 in remoteDispatchStorageVolUpload at remote_dispatch.h:14339
6  remoteDispatchStorageVolUploadHelper at remote_dispatch.h:14309
7  0x00007f094524a192 in virNetServerProgramDispatchCall at rpc/virnetserverprogram.c:437

Signed-off-by: Luyao Huang <lhuang at redhat.com>
---
 src/storage/storage_driver.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
index 7f33d6f..7f4de19 100644
--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
@@ -2111,8 +2111,9 @@ storageVolUpload(virStorageVolPtr obj,
             goto cleanup;
     }
 
-    ret = backend->uploadVol(obj->conn, pool, vol, stream,
-                             offset, length, flags);
+    if ((ret = backend->uploadVol(obj->conn, pool, vol, stream,
+                                  offset, length, flags)) < 0)
+        goto cleanup;
 
     /* Add cleanup callback - call after uploadVol since the stream
      * is then fully set up
-- 
1.8.3.1