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Weird minifilter leak?

Mauro_LeggieriMauro_Leggieri Member Posts: 107

Hi,

Today, on an updated Windows 10 VM, when shutting down my driver first I got this:

FLT_FILTER: ffffd38587602c60 "TestFlt" "[ERROR READING NAME]"
   InstanceList             : (ffffd38587602cc8)
      Resource (ffffd38587602d30) List [ffffd38587602d30-ffffd38587602d30] rCount=0 
   Object usage/reference information: 
      References to FLT_CONTEXT                : 0 
      Allocations of FLT_CALLBACK_DATA         : 0 
      Allocations of FLT_DEFERRED_IO_WORKITEM  : 0 
      Allocations of FLT_GENERIC_WORKITEM      : 2364 
      References to FLT_FILE_NAME_INFORMATION  : 0 
      Open files                               : 0 
      References to FLT_OBJECT                 : 0 
   List of objects used/referenced:: 
      FLT_VERIFIER_OBJECT: ffffd38592854fb0 
         Object: ffffd38572b56f90  Type: FLT_GENERIC_WORKITEM  RefCount: 00000001
      FLT_VERIFIER_OBJECT: ffffd385bcebefb0 
         Object: ffffd38572bc4f90  Type: FLT_GENERIC_WORKITEM  RefCount: 00000001
      FLT_VERIFIER_OBJECT: ffffd3859922cfb0

(lots of work items, some of them with refcount > 1)

After checking my code, I'm sure I'm not leaking any work item.

But then, then I run !fltkd.work

Throttled Work Ctrl: fffff80067b3b720 
   ThrottleLock             : (fffff80067b3b720)
   Queues                   : (fffff80067b3b728)
      CriticalQueue            : (fffff80067b3b728)
         RunningCount             : 0 
         RunningLimit             : 30 
         PendingWorkList          : (fffff80067b3b728)  Count=0
      DelayedQueue             : (fffff80067b3b740)
         RunningCount             : 2 
         RunningLimit             : 30 
         PendingWorkList          : (fffff80067b3b740)  Count=0
      HyperCriticalQue         : (fffff80067b3b758)
         RunningCount             : 0 
         RunningLimit             : 10 
         PendingWorkList          : (fffff80067b3b758)  Count=0
      FltpCriticalQueue        : (fffff80067b3b770)
         RunningCount             : -2023740080 
         RunningLimit             : -11387 
         PendingWorkList          : (fffff80067b3b770)  Count=1130501511
      FltpDelayedQueue         : (fffff80067b3b788)
         RunningCount             : 1726174024 
         RunningLimit             : -2048 
         PendingWorkList          : (fffff80067b3b788)  Count=3449555
      FltpHyperCriticalQue     : (fffff80067b3b7a0)
         RunningCount             : 0 
         RunningLimit             : 0 
         PendingWorkList          : (fffff80067b3b7a0)  Count=4531204

(I have to press ctrl+break several times in order to stop the query else takes forever)

Are those negative numbers ok or minifilter verifier is broken?

Regards,
Mauro.

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