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The best time to release FCB of file object created by IoCreateStreamFileObject

yu_shangyu_shang Member Posts: 41
edited June 2022 in NTFSD

Hi dear all,
If I understand it correctly , the best time (maybe only?) to release FCB of an ordinary file object is in response to IRP_MJ_CLOSE. But for file object created from IoCreateStreamFileObject by FSD , the receiver of IRP_MJ_CLOSE is not FSD. So what's the best time to release FCB in this case ?
I have the following use case

in response to IRP_MN_MOUNT_VOLUME
1. Fo=IoCreateStreamFileObject 
2. allocate and fill FsContext / SectionObjectPointer etc.
3. CcInitializeCacheMap
4. use cache
5. CcUninitializeCacheMap
6. ObDereferenceObject(Fo)
7. release FsContext / SectionObjectPointer allocated in step 2

In this scenario I am experiencing system crash. Because at step 7 there still exists active reference to Fo which is held by Cc. Cc will use FsContext later but it has been released.


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