Kernel 3.0.101-0.47.55 cifs mounts broken (KERNEL CIFS)

This document (7016703) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 11 Service Pack 3 (SLES 11 SP3)
SUSE Linux Enterprise Server 11 Service Pack 4 (SLES 11 SP4)

Situation

After a Kernel update from any Kernel to Kernel Version 3.0.101-0.47.55 mounts of cifs and smb shares to the Server are not working anymore. Typical Errors in /var/log/messages are :

Jul 4 11:19:07 mercury kernel: [41870.280427] CIFS VFS: cifs_calc_signature2: Can't generate signature
Jul 4 11:19:07 mercury kernel: [41870.280432]
Jul 4 11:19:07 mercury kernel: [41870.280439] CIFS VFS: Send error in SessSetup = -1
Jul 4 11:19:07 mercury kernel: [41870.280626] CIFS VFS: cifs_mount failed w/return code = -1

other services are unaffected and everything was working perfectly until after the server reboot or loading of the new cifs kernel module.

After patching, when encountering the additional error (listed below) about packet signing, it may be required to add the sec=ntlmv2i option to the mount command or edit the security flags to enable signing. This is do to the fact that in this scenario the server *REQUIRES* SMB signatures or packet signing.

Aug 7 14:26:30 srv01 kernel: [90560.145451] CIFS VFS: cifs_calc_signature2: Can't generate signature
Aug 7 14:26:30 srv01 kernel: [90560.145452]
Aug 7 14:26:30 srv01 kernel: [90560.145454] CIFS VFS: Send error in SessSetup = -1
Aug 7 14:26:30 srv01 kernel: [90560.145486] CIFS VFS: cifs_mount failed w/return code = -1
Aug 7 14:27:16 srv01 kernel: [90606.436709] CIFS VFS: Server requires packet signing to be enabled in /proc/fs/cifs/SecurityFlags.
Aug 7 14:27:16 srv01 kernel: [90606.436746] CIFS VFS: cifs_mount failed w/return code = -95

When receiving the following error (as listed below) when using the option sec=ntlmv2i, then please proceed using the option sec=ntlmsspi instead.

Aug 12 20:12:56 sles11 kernel: [ 3725.415369] Status code returned 0xc000000d NT_STATUS_INVALID_PARAMETER
Aug 12 20:12:56 sles11 kernel: [ 3725.415376] CIFS VFS: Send error in SessSetup = -22
Aug 12 20:12:56 sles11 kernel: [ 3725.415428] CIFS VFS: cifs_mount failed w/return code = -22

Resolution

For SLES 11 SP3 :

Update to any SLES 11 SP3 Kernel with a higher version than 3.0.101-0.47.55 if available.

Until this is available download and install PTF Kernels from

x86_64 Kernel:

https://ptf.suse.com/f2cf38b50ed714a8409693060195b235/sles11-sp3/8843/x86_64/20150717

s390x Kernel:

https://ptf.suse.com/f2cf38b50ed714a8409693060195b235/sles11-sp3/8843/s390x/20150723

For SLES 11 SP4:

PTFs are available at:

x86_64 kernel:
https://ptf.suse.com/f2cf38b50ed714a8409693060195b235/sles11-sp4/9197/x86_64/20150831/

s390x kernel:
https://ptf.suse.com/f2cf38b50ed714a8409693060195b235/sles11-sp4/9197/s390x/20150831/

Cause

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.