smbd/ioctl: match WS2016 ReFS set compression behaviour

ReFS doesn't support compression, but responds to set-compression FSCTLs
with NT_STATUS_OK if (and only if) the requested compression format is
COMPRESSION_FORMAT_NONE.

Bug: https://bugzilla.samba.org/show_bug.cgi?id=12144

Reported-by: Nick Barrett <nick@barrett.org.nz>
Signed-off-by: David Disseldorp <ddiss@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Mon Jan  9 23:14:28 CET 2017 on sn-devel-144

diff --git a/source3/smbd/smb2_ioctl_filesys.c b/source3/smbd/smb2_ioctl_filesys.c
index f2a05540c77f8d0c792024586371a7d8888933d3..64b54548197d1f51bcb9f69b1255f76eeaceb2a6 100644 (file)
--- a/source3/smbd/smb2_ioctl_filesys.c
+++ b/source3/smbd/smb2_ioctl_filesys.c
@@ -104,11 +104,6 @@ static NTSTATUS fsctl_set_cmprn(TALLOC_CTX *mem_ctx,
                return status;
        }
 
-       if ((fsp->conn->fs_capabilities & FILE_FILE_COMPRESSION) == 0) {
-               DEBUG(4, ("FS does not advertise compression support\n"));
-               return NT_STATUS_NOT_SUPPORTED;
-       }
-
        ndr_ret = ndr_pull_struct_blob(in_input, mem_ctx, &cmpr_state,
                        (ndr_pull_flags_fn_t)ndr_pull_compression_state);
        if (ndr_ret != NDR_ERR_SUCCESS) {
@@ -116,15 +111,22 @@ static NTSTATUS fsctl_set_cmprn(TALLOC_CTX *mem_ctx,
                return NT_STATUS_INVALID_PARAMETER;
        }
 
-       status = SMB_VFS_SET_COMPRESSION(fsp->conn,
-                                        mem_ctx,
-                                        fsp,
-                                        cmpr_state.format);
-       if (!NT_STATUS_IS_OK(status)) {
-               return status;
+       status = NT_STATUS_NOT_SUPPORTED;
+       if (fsp->conn->fs_capabilities & FILE_FILE_COMPRESSION) {
+               status = SMB_VFS_SET_COMPRESSION(fsp->conn,
+                                                mem_ctx,
+                                                fsp,
+                                                cmpr_state.format);
+       } else if (cmpr_state.format == COMPRESSION_FORMAT_NONE) {
+               /*
+                * bso#12144: The underlying filesystem doesn't support
+                * compression. We should still accept set(FORMAT_NONE) requests
+                * (like WS2016 ReFS).
+                */
+               status = NT_STATUS_OK;
        }
 
-       return NT_STATUS_OK;
+       return status;
 }
 
 static NTSTATUS fsctl_zero_data(TALLOC_CTX *mem_ctx,