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

[Ralph Boehme]

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://samba.org/
Samba Developer, SerNet GmbH   https://sernet.de/en/samba/
GPG-Fingerprint   FAE2C6088A24252051C559E4AA1E9B7126399E46
-------------- next part --------------
A non-text attachment was scrubbed...
Name: windows2016-READ_CONTROL-no-lease-break.pcapng
Type: application/x-pcapng
Size: 47024 bytes
Desc: not available
URL: <http://lists.samba.org/pipermail/cifs-protocol/attachments/20200303/174557aa/windows2016-READ_CONTROL-no-lease-break-0001.bin>