Nate Collins <ncollins@xxxxxxxxxxx> writes: > I initially posted this to the Samba mailing list, where it didn't > receive much attention, but it might be more appropriate for a > CIFS-specific mailing list. Per the subject, this may be an > Ubuntu-specific bug, but I don't have the familiarity with CIFS to > claim this is so and that nothing is wrong with my setup. You can try to look at what happens in Wireshark. If you are getting STATUS_ACCESS_DENIED during session setup it could be a signing problem or kerberos issue. I would be interesting to see to which request are you getting that error back from anyway. Ubuntu 18 is from 2018 right? There have been multiple regressions and fixes related to signing since then. After a quick scan I see these fixes (from most recent to oldest): 05946d4b7a73 cifs: Fix preauth hash corruption edad734c74a4 smb3: use SMB2_SIGNATURE_SIZE define cc95b6772790 cifs: fix channel signing ff6b6f3f9160 cifs: Always update signing key of first channel 46f17d17687e smb3: fix signing verification of large reads 8c11a607d1d9 SMB3: Fix SMB3.1.1 guest mounts to Samba e71ab2aa06f7 cifs: allow guest mounts to work for smb3.11 a5c62f4833c2 CIFS: fix uninitialized ptr deref in smb2 signing a12d0c590cc7 cifs: Make sure all data pages are signed correctly 8de8c4608fe9 cifs: Fix validation of signed data in smb2 27c32b49c3db cifs: Fix validation of signed data in smb3+ 83ffdeadb46b cifs: Fix invalid check in __cifs_calc_signature() ... For debugging keyrings you can write a shell script wrapper for all the cifs keys defined in /etc/request-keys.conf. This allows you to log calls, strace the bins, etc. See Sashin's blog: http://sprabhu.blogspot.com/2014/12/debugging-calls-to-cifsupcall.html If you can recompile the cifs-utils upcall bins you can add calls to log PID and sleep so you can attach gdb and step into it, can be really useful as well. Cheers, -- Aurélien Aptel / SUSE Labs Samba Team GPG: 1839 CB5F 9F5B FB9B AA97 8C99 03C8 A49B 521B D5D3 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg, DE GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 247165 (AG München)
