regression in handlig of export table

[kofemann]

The current master (commit eb9a7e3) contains a regression in the handling of export tables and reject mounting of the nfs server. The issue was discovered during testing with dCache integration.

[DmitryLitvintsev]

How could that commit that fixed a typo in the comment could have caused this bug?

[kofemann]

It's not that commit, it's more currently know bad state (as in bisec).

[kofemann]

bisected to

9e8063234e4b649d3e748474d8d425f53ce64b8 is the first bad commit
commit 09e8063234e4b649d3e748474d8d425f53ce64b8
Author: Christian Kohlschütter <christian@kohlschutter.com>
Date:   Fri Jun 27 19:34:32 2025 +0200

    core: PseudoFS: Properly resolve the inner root inode
    
    When we try to resolve the inner FS's root inode given a pseudo inode in
    PseudoFS, we can directly return the inner FS's root inode as returned
    by VirtualFileSystem#getRootInode(), which is most likely cached,
    instead of creating new Inode instances all over again.
    
    This further reduces the number of Inode allocations.
    
    Also fail with BadHandleException for any other pseudo inode because
    they will by definition be invalid in the underlying file system.
    
    Related: https://github.com/dCache/nfs4j/discussions/149
    Signed-off-by: Christian Kohlschütter <chrixxxcom>

 core/src/main/java/org/dcache/nfs/vfs/PseudoFs.java | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

tast case:

package org.dcache.nfs.vfs;

import org.dcache.nfs.ExportTable;
import org.dcache.nfs.FsExport;
import org.dcache.oncrpc4j.rpc.RpcAuth;
import org.dcache.oncrpc4j.rpc.RpcAuthType;
import org.dcache.oncrpc4j.rpc.RpcCall;
import org.dcache.oncrpc4j.rpc.RpcTransport;
import org.junit.Before;
import org.junit.Test;

import javax.security.auth.Subject;
import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.util.stream.Stream;

import static org.dcache.nfs.util.UnixSubjects.toSubject;
import static org.mockito.BDDMockito.given;
import static org.mockito.Mockito.mock;


public class PseudoFsTestOne {

    private final Subject ROOT = toSubject(0, 0);

    private final static InetSocketAddress localAddress = new InetSocketAddress(31415);
    private VirtualFileSystem vfs;
    private FsExport mockedExport;
    private RpcTransport mockedTransport;
    private RpcCall mockedRpc;
    private RpcAuth mockedAuth;
    private PseudoFs pseudoFs;
    private Inode fsRoot;

    @Before
    public void setUp() throws IOException {

        vfs = new DummyVFS();
        fsRoot = vfs.getRootInode();

        mockedTransport = mock(RpcTransport.class);
        mockedRpc = mock(RpcCall.class);
        mockedAuth = mock(RpcAuth.class);
        mockedExport = mock(FsExport.class);
        given(mockedExport.getAnonUid()).willReturn(FsExport.DEFAULT_ANON_UID);
        given(mockedExport.getAnonGid()).willReturn(FsExport.DEFAULT_ANON_GID);
    }


    @Test
    public void shouldAllowListing() throws IOException {
        InetSocketAddress clientEndpoint = new InetSocketAddress("192.168.1.1", 314);

        Subject subject = toSubject(17, 17);
        Inode parent = vfs.mkdir(fsRoot, "exports", subject, 0755);
        vfs.mkdir(parent, "data", subject, 0755);

        given(mockedTransport.getRemoteSocketAddress()).willReturn(clientEndpoint);
        given(mockedAuth.getSubject()).willReturn(ROOT);
        given(mockedAuth.type()).willReturn(RpcAuthType.UNIX);
        given(mockedRpc.getTransport()).willReturn(mockedTransport);
        given(mockedRpc.getCredential()).willReturn(mockedAuth);

        FsExport export1 = new FsExport.FsExportBuilder()
                .rw()
                .trusted()
                .withoutAcl()
                .withSec(FsExport.Sec.SYS)
                .forClient("192.168.1.0/24")
                .build("/exports/data");

        var exportTable = new ExportTable() {

            @Override
            public Stream<FsExport> exports() {
                throw new RuntimeException("not used in this test");
            }

            @Override
            public Stream<FsExport> exports(InetAddress client) {
                return Stream.of(export1);
            }

            @Override
            public FsExport getExport(String path, InetAddress client) {
                return export1.getPath().equals(path) ? export1 : null;
            }

            @Override
            public FsExport getExport(int index, InetAddress client) {
                return  export1.getIndex() == index ? export1 : null;
            }
        };

        pseudoFs = new PseudoFs(vfs, mockedRpc, exportTable);
        Inode pseudoRoot = pseudoFs.getRootInode();
        pseudoFs.list(pseudoRoot, DirectoryStream.ZERO_VERIFIER, 0);
    }
}

[kohlschuetter]

I have a fix, forthcoming

[kohlschuetter]

Please ignore b7f4379

The proper fix is to simply not throw a BadHandleException.