[Pkg-samba-maint] Bug#943903: samba 2:4.11.1+dfsg-1 server breaks mount.cifs from cifs-utils 2:6.9-1

[Marvin Renich]

Package: samba
Version: 2:4.11.1+dfsg-1
Severity: normal

I plan to clone this bug to cifs-utils, as it is unclear which package has the bug.

After upgrading from samba 2:4.9.13+dfsg-1 to 2:4.11.0+dfsg-10 on a server machine, mount.cifs from cifs-utils 2:6.9-1
on a different machine fails to connect with "mount error(13): Permission denied".  Subsequently upgrading samba to
2:4.11.1+dfsg-1 did not help.

Downgrading samba to stable 2:4.9.5+dfsg-5+deb10u1 on the server fixes the problem.  Adding a snapshot version to figure
out what needed to be downgraded to get version 2:4.9.13+dfsg-1 was deemed not worth the effort, as my daily backup on
the client machine (which mounts the remote cifs share) was running fine when the server had 2:4.9.13+dfsg-1.

-- Package-specific info:
* /etc/samba/smb.conf present, but not attached
* /var/lib/samba/dhcp.conf present, but not attached

-- System Information:
Debian Release: bullseye/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'stable-updates'), (500, 'oldstable-updates'), (500, 'stable'), (500, 'oldstable'), (200, 'unstable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 5.2.0-3-amd64 (SMP w/8 CPU cores)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)
LSM: AppArmor: enabled

Versions of packages samba depends on:
ii  adduser              3.118
ii  dpkg                 1.19.7
ii  init-system-helpers  1.57
ii  libbsd0              0.10.0-1
ii  libc6                2.29-2
ii  libgnutls30          3.6.9-5+b1
ii  libldb2              2:2.0.7-3
ii  libpam-modules       1.3.1-5
ii  libpam-runtime       1.3.1-5
ii  libpopt0             1.16-14
ii  libpython3.7         3.7.5~rc1-2
ii  libtalloc2           2.3.0-2
ii  libtasn1-6           4.14-3
ii  libtdb1              1.4.2-2
ii  libtevent0           0.10.1-3
ii  libwbclient0         2:4.11.1+dfsg-1
ii  lsb-base             11.1.0
ii  procps               2:3.3.15-2+b1
ii  python3              3.7.5-1
ii  python3-dnspython    1.16.0-1
ii  python3-samba        2:4.11.1+dfsg-1
ii  samba-common         2:4.11.1+dfsg-1
ii  samba-common-bin     2:4.11.1+dfsg-1
ii  samba-libs           2:4.11.1+dfsg-1
ii  tdb-tools            1.4.2-2

Versions of packages samba recommends:
ii  attr                1:2.4.48-5
ii  logrotate           3.15.1-1
ii  samba-dsdb-modules  2:4.11.1+dfsg-1
ii  samba-vfs-modules   2:4.11.1+dfsg-1

Versions of packages samba suggests:
pn  bind9          <none>
pn  bind9utils     <none>
pn  ctdb           <none>
pn  ldb-tools      <none>
ii  ntp            1:4.2.8p13+dfsg-2
pn  smbldap-tools  <none>
ii  ufw            0.36-1
ii  winbind        2:4.11.1+dfsg-1

-- debconf information:
  samba/run_mode: daemons
  samba-common/title: