[cifs-protocol] [REG:120030321000983] SMB2: opening file for READ_CONTROL doesn't trigger lease break

[Jeff McCashland]

Hi slow,

I love the trace you sent, it's beautiful. I've verified that Frame 139 unexpectedly does not break lease. 

I thought it was interesting that READ_EA access also breaks the lease, but I'm not certain why. 

Thank you for pointing this out and providing the trace. I will file a request to update the doc.

Best regards,
Jeff McCashland | Senior Escalation Engineer | Microsoft Protocol Open Specifications Team 
Phone: +1 (425) 703-8300 x38300 | Hours: 9am-5pm | Time zone: (UTC-08:00) Pacific Time (US and Canada)
Local country phone number found here: http://support.microsoft.com/globalenglish | Extension 1138300
We value your feedback.  My manager is Jeremy Chapman (jeremyc), +1 (469) 775-2475

-----Original Message-----
From: Jeff McCashland <jeffm at microsoft.com> 
Sent: Tuesday, March 3, 2020 6:33 AM
To: Ralph Boehme <slow at samba.org>
Cc: cifs-protocol at lists.samba.org; support <support at mail.support.microsoft.com>
Subject: [REG:120030321000983] SMB2: opening file for READ_CONTROL doesn't trigger lease break

[DocHelp to BCC, support on CC, SR ID on Subject]

Hi slow,

Thank you for sending in your question and trace. We have created SR 120030321000983 to track this issue. I will review your trace and follow up.

Best regards,
Jeff McCashland | Senior Escalation Engineer | Microsoft Protocol Open Specifications Team
Phone: +1 (425) 703-8300 x38300 | Hours: 9am-5pm | Time zone: (UTC-08:00) Pacific Time (US and Canada) Local country phone number found here: https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fsupport.microsoft.com%2Fglobalenglish&data=02%7C01%7Cjeffm%40microsoft.com%7C667b2ec88e304d007fa608d7bf7fc3b0%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637188427782105524&sdata=MWDwCaq3xZCb9LVntik9EFZO%2Fpbj%2BCg2NU63US1uciw%3D&reserved=0 | Extension 1138300 We value your feedback.  My manager is Jeremy Chapman (jeremyc), +1 (469) 775-2475

-----Original Message-----
From: Ralph Boehme <slow at samba.org>
Sent: Tuesday, March 3, 2020 2:57 AM
To: Interoperability Documentation Help <dochelp at microsoft.com>
Cc: cifs-protocol at lists.samba.org
Subject: [EXTERNAL] SMB2: opening file for READ_CONTROL doesn't trigger lease break

Hello dochelp,

according to MS-FSA 2.1.4.12 opening a file with at most FILE_READ_ATTRIBUTES, FILE_WRITE_ATTRIBUTES, or SYNCHRONIZE avoids triggering an oplock break:

  If OpParams.DesiredAccess contains no flags other than
  FILE_READ_ATTRIBUTES, FILE_WRITE_ATTRIBUTES, or SYNCHRONIZE
  the algorithm returns at this point.

However, testing all valid file access bits individually against a Windows 2016 server reveals that an access mask of READ_CONTROL also doesn't trigger an oplock break.

Attached is a network trace of a testcase that tests all possible file access masks.

The testcase with READ_CONTROL begins in packet 137 (request open with RWH lease), the open with READ_CONTROL is in packet 139.

Can you clarify?

Thanks!
-slow

--
Ralph Boehme, Samba Team                https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsamba.org%2F&data=02%7C01%7Cjeffm%40microsoft.com%7C667b2ec88e304d007fa608d7bf7fc3b0%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637188427782105524&sdata=U%2BoR4clzvSJDabbx%2FkvQvH0YZsxNN4dAB49qq8FozaU%3D&reserved=0
Samba Developer, SerNet GmbH   https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsernet.de%2Fen%2Fsamba%2F&data=02%7C01%7Cjeffm%40microsoft.com%7C667b2ec88e304d007fa608d7bf7fc3b0%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637188427782105524&sdata=75szehwAWdQPCIYOiboZmgr7t6hjlqiW3Bnemvw9oBg%3D&reserved=0
GPG-Fingerprint   FAE2C6088A24252051C559E4AA1E9B7126399E46