NullPointerException seen in the field for jcifs.util.transport.Response.isReceived()

[courville]

Seen in the field with nova my android video player app reported on my sentry crashnalytics backend (no clue what triggers it). Here is the stacktrace collected:

java.lang.NullPointerException: Attempt to invoke interface method 'boolean jcifs.util.transport.Response.isReceived()' on a null object reference
    at jcifs.smb.SmbTransportImpl.sendrecv(SmbTransportImpl.java:1053)
    at jcifs.smb.SmbTransportImpl.send(SmbTransportImpl.java:1549)
    at jcifs.smb.SmbTransportImpl.send(SmbTransportImpl.java:1513)
    at jcifs.smb.SmbSessionImpl.sessionSetupSMB1(SmbSessionImpl.java:907)
    at jcifs.smb.SmbSessionImpl.sessionSetup(SmbSessionImpl.java:494)
    at jcifs.smb.SmbSessionImpl.send(SmbSessionImpl.java:369)
    at jcifs.smb.SmbSessionImpl.send(SmbSessionImpl.java:347)
    at jcifs.smb.SmbTreeImpl.treeConnect(SmbTreeImpl.java:611)
    at jcifs.smb.SmbTreeConnection.connectTree(SmbTreeConnection.java:614)
    at jcifs.smb.SmbTreeConnection.connectHost(SmbTreeConnection.java:568)
    at jcifs.smb.SmbTreeConnection.connectHost(SmbTreeConnection.java:489)
    at jcifs.smb.SmbTreeConnection.connect(SmbTreeConnection.java:465)
    at jcifs.smb.SmbTreeConnection.connectWrapException(SmbTreeConnection.java:426)
    at jcifs.smb.SmbFile.ensureTreeConnected(SmbFile.java:559)
    at jcifs.smb.SmbEnumerationUtil.doEnum(SmbEnumerationUtil.java:221)
    at jcifs.smb.SmbEnumerationUtil.listFiles(SmbEnumerationUtil.java:279)
    at jcifs.smb.SmbFile.listFiles(SmbFile.java:1287)
    at com.archos.filecorelibrary.jcifs.JcifListingEngine$JcifListingThread.run(JcifListingEngine.java:113)

jcifs master is used.

[mbechler]

Analysis revealed one situtation in which that exception can occur, but I'm not sure that could have been reached in your case, and therefore whether this is the proper fix.

[courville]

Thanks, I will deploy the current master in the field and monitor if the issue is reproduced.

[mbechler]

Going after that NPE I also came across a logic error that prevented SMB1's AndX chaining from being used which was supposed to be enabled by default. Currently that is enabled in master, but I'm not sure we should by default at this point. If you see any other SMB1 related errors that would be very helpful information as well.