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

[Mathieu Parent]

Le jeu. 31 oct. 2019 à 17:03, Marvin Renich <mrvn at renich.org> a écrit :
>
> 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.

What is the kernel version on the client side?

Try to force the CIFS version with vers= in the mount options.

> vers=arg
>   SMB protocol version. Allowed values are:
>
>   • 1.0 - The classic CIFS/SMBv1 protocol.
>
>   • 2.0  -  The  SMBv2.002 protocol. This was initially introduced in Windows Vista Service Pack 1, and Windows Server 2008. Note that
>     the initial release version of Windows Vista spoke a slightly different dialect (2.000) that is not supported.
>
>   • 2.1 - The SMBv2.1 protocol that was introduced in Microsoft Windows 7 and Windows Server 2008R2.
>
>   • 3.0 - The SMBv3.0 protocol that was introduced in Microsoft Windows 8 and Windows Server 2012.
>
>   • 3.1.1 or 3.11 - The SMBv3.1.1 protocol that was introduced in Microsoft Windows Server 2016.
>
>   Note too that while this option governs the protocol version used, not all features of each version are available.
>
>   The default since v4.13.5 is for the client and server to negotiate the highest possible version greater than or equal  to  2.1.  In
>   kernels prior to v4.13, the default was 1.0. For kernels between v4.13 and v4.13.5 the default is 3.0.


Ref: https://manpages.debian.org/buster/cifs-utils/mount.cifs.8.en.html

Regards

-- 
Mathieu Parent