A client that supports SMB3 will do a signed FSCTL_VALIDATE_NEGOTIATE_INFO after a tree connect. This FSCTL_VALIDATE_NEGOTIATE_INFO call contains the client capabilities, client guid, security mode and the array of supported dialects. But if SMB 2.02 is negotiated the doesn't send these values to the server in the first connection attempt (when the client starts with a SMB1 Negotiate). Windows servers that only support SMB2 just return NT_STATUS_FILE_CLOSED as answer to FSCTL_VALIDATE_NEGOTIATE_INFO. We should do the same if we just pretend to support SMB 2.02, as SMB 2.10 always include an SMB2 Negotiate request we can leave it as is.
Created attachment 13200 [details] Possible patch for master (needs regression tests)
Created attachment 13327 [details] Patch for v4-6-test
Created attachment 13328 [details] Patch for v4-5-test
Reassigning to Karolin for inclusion in 4.5 and 4.6
(In reply to Ralph Böhme from comment #4) Pushed to autobuild-v4-{6,5}-test.
(In reply to Karolin Seeger from comment #5) Pushed to both branches. Closing out bug report. Thanks!