VERSION: Re-enable GIT_SNAPSHOTS.

[Samba.git] / WHATSNEW.txt

                   =============================
                   Release Notes for Samba 4.6.1
                           March 23, 2017
                   =============================


This is a security release in order to address the following defect:

o  CVE-2017-2619 (Symlink race allows access outside share definition)

=======
Details
=======

o  CVE-2017-2619:
   All versions of Samba prior to 4.6.1, 4.5.7, 4.4.11 are vulnerable to
   a malicious client using a symlink race to allow access to areas of
   the server file system not exported under the share definition.

   Samba uses the realpath() system call to ensure when a client requests
   access to a pathname that it is under the exported share path on the
   server file system.

   Clients that have write access to the exported part of the file system
   via SMB1 unix extensions or NFS to create symlinks can race the server
   by renaming a realpath() checked path and then creating a symlink. If
   the client wins the race it can cause the server to access the new
   symlink target after the exported share path check has been done. This
   new symlink target can point to anywhere on the server file system.

   This is a difficult race to win, but theoretically possible. Note that
   the proof of concept code supplied wins the race reliably only when
   the server is slowed down using the strace utility running on the
   server. Exploitation of this bug has not been seen in the wild.


Changes since 4.6.0:
--------------------

o  Jeremy Allison <jra@samba.org>
   * BUG 12496: CVE-2017-2619: Symlink race permits opening files outside share
     directory.

o  Ralph Boehme <slow@samba.org>
   * BUG 12496: CVE-2017-2619: Symlink race permits opening files outside share
     directory.


#######################################
Reporting bugs & Development Discussion
#######################################

Please discuss this release on the samba-technical mailing list or by
joining the #samba-technical IRC channel on irc.freenode.net.

If you do report problems then please try to send high quality
feedback. If you don't provide vital information to help us track down
the problem then you will probably be ignored.  All bug reports should
be filed under the "Samba 4.1 and newer" product in the project's Bugzilla
database (https://bugzilla.samba.org/).


======================================================================
== Our Code, Our Bugs, Our Responsibility.
== The Samba Team
======================================================================


Release notes for older releases follow:
----------------------------------------

                   ==============================
                   Release Notes for Samba 4.6.0
                           March 7, 2017
                   ==============================


This is the first stable release of Samba 4.6.
Please read the release notes carefully before upgrading.


UPGRADING
=========

ID Mapping
----------
We discovered that the majority of users have an invalid or incorrect
ID mapping configuration. We implemented checks in the 'testparm' tool to
validate the ID mapping configuration. You should run it and check if it prints
any warnings or errors after upgrading! If it does you should fix them. See the
'IDENTITY MAPPING CONSIDERATIONS' section in the smb.conf manpage.
There are some ID mapping backends which are not allowed to be used for the
default backend. Winbind will no longer start if an invalid backend is
configured as the default backend.

To avoid problems in future we advise all users to run 'testparm' after
changing the smb.conf file!

vfs_fruit option "fruit:resource" spelling correction
-----------------------------------------------------

Due to a spelling error in the vfs_fruit option parsing for the "fruit:resource"
option, users who have set this option in their smb.conf were still using the
default setting "fruit:resource = file" as the parser was looking for the string
"fruit:ressource" (two "s").

After upgrading to this Samba version 4.6, you MUST either remove the option
from your smb.conf or set it to the default "fruit:resource = file", otherwise
your macOS clients will not be able to access the resource fork data.

This version Samba 4.6 accepts both the correct and incorrect spelling, but the
next Samba version 4.7 will not accept the wrong spelling.

Users who were using the wrong spelling "ressource" with two "s" can keep the
setting, but are advised to switch to the correct spelling.

vfs_fruit Netatalk metadata xattr name on *BSD
----------------------------------------------

Users on *BSD must rename the metadata xattr used by vfs_fruit when
using the default setting "fruit:metadata = netatalk".

Due to a glitch in the Samba xattr API compatibility layer for FreeBSD and a
mistake in vfs_fruit, vfs_fruit ended up using the wrong xattr name when
configured with "fruit:metadata = netatalk" (default). Instead of the correct

  org.netatalk.Metadata

it used

  netatalk.Metadata

Starting with Samba 4.6 vfs_fruit will use the correct "org.netatalk.Metadata"
which means existing installations must rename this xattrs. For this purpose
Samba now includes a new tool `mvxattr`. See below for further details.


NEW FEATURES/CHANGES
====================

Kerberos client encryption types
--------------------------------
Some parts of Samba (most notably winbindd) perform Kerberos client
operations based on a Samba-generated krb5.conf file. A new
parameter, "kerberos encryption types" allows configuring the
encryption types set in this file, thereby allowing the user to
enforce strong or legacy encryption in Kerberos exchanges.

The default value of "all" is compatible with previous behavior, allowing
all encryption algorithms to be negotiated. Setting the parameter to "strong"
only allows AES-based algorithms to be negotiated. Setting the parameter to
"legacy" allows only RC4-HMAC-MD5 - the legacy algorithm for Active Directory.
This can solves some corner cases of mixed environments with Server 2003R2 and
newer DCs.

Printing
--------
Support for uploading printer drivers from newer Windows clients (Windows 10)
has been added until our implementation of [MS-PAR] protocol is ready.
Several issues with uploading different printing drivers have been addressed.

The OS Version for the printing server has been increased to announce
Windows Server 2003 R2 SP2. If a driver needs a newer version then you should
check the smb.conf manpage for details.

New option for owner inheritance
--------------------------------
The "inherit owner" smb.conf parameter instructs smbd to set the
owner of files to be the same as the parent directory's owner.
Up until now, this parameter could be set to "yes" or "no".
A new option, "unix only", enables this feature only for the UNIX owner
of the file, not affecting the SID owner in the Windows NT ACL of the
file. This can be used to emulate something very similar to folder quotas.

Multi-process Netlogon support
------------------------------

The Netlogon server in the Samba AD DC can now run as multiple
processes.  The Netlogon server is a part of the AD DC that handles
NTLM authentication on behalf of domain members, including file
servers, NTLM-authenticated web servers and 802.1x gateways.  The
previous restriction to running as a single process has been removed,
and it will now run in the same process model as the rest of the
'samba' binary.

As part of this change, the NETLOGON service will now run on a distinct
TCP port, rather than being shared with all other RPC services (LSA,
SAMR, DRSUAPI etc).

New options for controlling TCP ports used for RPC services
-----------------------------------------------------------

The new 'rpc server port' option controls the default port used for
RPC services other than Netlogon.  The Netlogon server honours instead
the 'rpc server port:netlogon' option.  The default value for both
these options is the first available port including or after 1024.

AD LDAP and replication performance improvements
------------------------------------------------

Samba's LDB (the database holding the AD directory tree, as seen via
LDAP) and our DRSUAPI replication code continues to improve,
particularly in respect to the handling of large numbers of objects or
linked attributes.

 * We now respect an 'uptodateness vector' which will dramatically
   reduce the over-replication of links from new DCs.

 * We have also made the parsing of on-disk linked attributes much
   more efficient.

 * We rely on ldb 1.1.28.  This ldb version has improved memory
   handling for ldb search results, improving poorly indexed and
   unindexed search result processing speed by around 20%.

DNS improvements
----------------

The samba-tool dns subcommand is now much more robust and can delete
records in a number of situations where it was not possible to do so
in the past.

On the server side, DNS names are now more strictly validated.

CTDB changes
------------

* "ctdb event" is a new top-level command for interacting with event scripts

  "ctdb event status" replaces "ctdb scriptstatus" - the latter is
  maintained for backward compatibility but the output format has been
  cleaned up

  "ctdb event run" replaces "ctdb eventscript"

  "ctdb event script enable" replaces "ctdb enablescript"

  "ctdb event script disable" replaces "ctdb disablescript"

  The new command "ctdb event script list" lists event scripts.

* CTDB's back-end for running event scripts has been replaced by a
  separate, long-running daemon ctdbd_eventd.

* Running ctdb interactively will log to stderr

* CTDB logs now include process id for each process

* CTDB tags log messages differently.  Changes include:

  ctdb-recoverd: Messages from CTDB's recovery daemon
  ctdb-recovery: Messages from CTDB database recovery
  ctdb-eventd: Messages from CTDB's event daemon
  ctdb-takeover: Messages from CTDB's public IP takeover subsystem

* The mapping between symbolic and numeric debug levels has changed

  Configurations containing numeric debug levels should be updated.
  Symbolic debug levels are recommended.  See the DEBUG LEVEL section
  of ctdb(7) for details.

* Tunable IPAllocAlgorithm replaces LCP2PublicIPs, DeterministicIPs

  See ctdb-tunables(7) for details.

* CTDB's configuration tunables should be consistently set across a cluster

  This has always been the cases for most tunables but this fact is
  now documented.

* CTDB ships with recovery lock helper call-outs for etcd and Ceph RADOS

  To build/install these, use the "--enable-etcd-reclock" and
  "--enable-ceph-reclock" configure options.

winbind changes
---------------

winbind contains code that tries to emulate the group membership calculation
that domain controllers do when a user logs in. This group membership calculation
is a very complex process, in particular for domain trust relationship
situations. Also, in many scenarios it is impossible for winbind to
correctly do this calculation due to access restrictions in the
domains: winbind using its machine account simply does not have the
rights to ask for an arbitrary user's group memberships.

When a user logs in to a Samba server, the domain controller correctly
calculates the user's group memberships authoritatively and makes the
information available to the Samba server. This is the only reliable
way Samba can get informed about the groups a user is member of.

Because of its flakiness, the fallback group membership code is unwished,
and our code pathes try hard to only use of the group memberships
calculated by the domain controller.

However, a lot of admins rely on the fallback behavior in order to support
access for nfs access, ssh public key authentication and passwordless sudo.

That's the reason for changing this back between 4.6.0rc4 and 4.6.0
(See BUG 12612).

The winbind change to simplify the calculation of supplementary groups to make
it more reliable and predictable has been deferred to 4.7 or later.

This means that 'id <username>' without the user having logged in
previously works similar to 4.5.

winbind primary group and nss info
----------------------------------

With 4.6, it will be possible to optionally use the primary group as
set in the "Unix Attributes" tab for the local unix token of a domain
user.  Before 4.6, the Windows primary group was always chosen as
primary group for the local unix token.

To activate the unix primary group, set

idmap config <DOMAIN> : unix_primary_group = yes

Similarly, set

idmap config <DOMAIN> : unix_nss_info = yes

to retrieve the home directory and login shell from the "Unix
Attributes" of the user. This supersedes the "winbind nss info"
parameter with a per-domain configuration option.

mvxattr
-------

mvxattr is a simple utility to recursively rename extended attributes of all
files and directories in a directory tree.

  Usage: mvxattr -s STRING -d STRING PATH [PATH ...]
    -s, --from=STRING         xattr source name
    -d, --to=STRING           xattr destination name
    -l, --follow-symlinks     follow symlinks, the default is to ignore them
    -p, --print               print files where the xattr got renamed
    -v, --verbose             print files as they are checked
    -f, --force               force overwriting of destination xattr

  Help options:
    -?, --help                Show this help message
    --usage                   Display brief usage message

idmap_hash
----------

The idmap_hash module is marked as deprecated with this release and will be
removed in a future version. See the manpage of the module for details.


smb.conf changes
================

  Parameter Name                Description             Default
  --------------                -----------             -------
  kerberos encryption types     New                     all
  inherit owner                 New option
  fruit:resource                Spelling correction
  lsa over netlogon             New (deprecated)        no
  rpc server port               New                     0


KNOWN ISSUES
============

https://wiki.samba.org/index.php/Release_Planning_for_Samba_4.6#Release_blocking_bugs


CHANGES SINCE 4.6.0rc4
======================

o  Jeremy Allison <jra@samba.org>
   * BUG 12592: Fix several issues found by covscan.
   * BUG 12608: s3: smbd: Restart reading the incoming SMB2 fd when the send
     queue is drained.

o  Ralph Boehme <slow@samba.org>
   * BUG 12427: vfs_fruit doesn't work with fruit:metadata=stream.
   * BUG 12526: vfs_fruit: Only veto AppleDouble files if "fruit:resource" is
     set to "file".
   * BUG 12604: vfs_fruit: Enabling AAPL extensions must be a global switch.

o  Volker Lendecke <vl@samba.org>
   * BUG 12612: Re-enable token groups fallback.

o  Stefan Metzmacher <metze@samba.org>
   * BUG 9048: Samba4 ldap error codes.
   * BUG 12557: gensec:spnego: Add debug message for the failed principal.
   * BUG 12605: s3:winbindd: Fix endless forest trust scan.
   * BUG 12612: winbindd: Find the domain based on the sid within
     wb_lookupusergroups_send().

o  Andreas Schneider <asn@samba.org>
   * BUG 12557: s3:librpc: Handle gss_min in gse_get_client_auth_token()
     correctly.
   * BUG 12582: idmap_hash: Add a deprecation message, improve the idmap_hash
     manpage.
   * BUG 12592: Fix several issues found by covscan.

o  Martin Schwenke <martin@meltin.net>
   * BUG 12592: ctdb-logging: CID 1396883 Dereference null return value
     (NULL_RETURNS).


CHANGES SINCE 4.6.0rc3
======================

o  Jeremy Allison <jra@samba.org>
   * BUG 12545: s3: rpc_server/mdssvc: Add attribute "kMDItemContentType".
   * BUG 12572: s3: smbd: Don't loop infinitely on bad-symlink resolution.

o  Ralph Boehme <slow@samba.org>
   * BUG 12490: vfs_fruit: Correct Netatalk metadata xattr on FreeBSD.
   * BUG 12536: s3/smbd: Check for invalid access_mask
     smbd_calculate_access_mask().
   * BUG 12591: vfs_streams_xattr: use fsp, not base_fsp.

o  Amitay Isaacs <amitay@gmail.com>
   * BUG 12580: ctdb-common: Fix use-after-free error in comm_fd_handler().
   * BUG 12595: build: Fix generation of CTDB manpages while creating tarball.

o  Bryan Mason <bmason@redhat.com>
   * BUG 12575: Modify smbspool_krb5_wrapper to just fall through to smbspool if
     AUTH_INFO_REQUIRED is not set or is not "negotiate".

o  Stefan Metzmacher <metze@samba.org>
   * BUG 11830: s3:winbindd: Try a NETLOGON connection with noauth over NCACN_NP
     against trusted domains.
   * BUG 12262: 'net ads testjoin' and smb access fails after winbindd changed the
     trust password.
   * BUG 12585: librpc/rpc: fix regression in
     NT_STATUS_RPC_ENUM_VALUE_OUT_OF_RANGE error mapping.
   * BUG 12586: netlogon_creds_cli_LogonSamLogon doesn't work without
     netr_LogonSamLogonEx.
   * BUG 12587: winbindd child segfaults on connect to an NT4 domain.
   * BUG 12588: s3:winbindd: Make sure cm_prepare_connection() only returns OK
     with a valid tree connect.
   * BUG 12598: winbindd (as member) requires kerberos against trusted ad domain,
     while it shouldn't.
   * BUG 12601: Backport pytalloc_GenericObject_reference() related changes to
     4.6.

o  Garming Sam <garming@catalyst.net.nz>
   * BUG 12600: dbchecker: Stop ignoring linked cases where both objects are
     alive.

o  Andreas Schneider <asn@samba.org>
   * BUG 12571: s3-vfs: Only walk the directory once in open_and_sort_dir().

o  Martin Schwenke <martin@meltin.net>
   * BUG 12589: CTDB statd-callout does not cause grace period when
     CTDB_NFS_CALLOUT="".
   * BUG 12595: ctdb-build: Fix RPM build.


CHANGES SINCE 4.6.0rc2
======================

o  Jeremy Allison <jra@samba.org>
   * BUG 12499: s3: vfs: dirsort doesn't handle opendir of "." correctly.
   * BUG 12546: s3: VFS: vfs_streams_xattr.c: Make streams_xattr_open() store
     the same path as streams_xattr_recheck().
   * BUG 12531: Make vfs_shadow_copy2 cope with server changing directories.

o  Andrew Bartlett <abartlet@samba.org>
   * BUG 12543: samba-tool: Correct handling of default value for use_ntvfs and
     use_xattrs.
   * BUG 12573: Samba < 4.7 does not know about compatibleFeatures and
     requiredFeatures.
   * BUG 12577: 'samba-tool dbcheck' gives errors on one-way links after a
     rename.

o  Ralph Boehme <slow@samba.org>
   * BUG 12184: s3/rpc_server: Shared rpc modules loading.
   * BUG 12520: Ensure global "smb encrypt = off" is effective.
   * BUG 12524: s3/rpc_server: Move rpc_modules.c to its own subsystem.
   * BUG 12541: vfs_fruit: checks wrong AAPL config state and so always uses
     readdirattr.

o  Volker Lendecke <vl@samba.org>
   * BUG 12551: smbd: Fix "map acl inherit" = yes.

o  Stefan Metzmacher <metze@samba.org>
   * BUG 12398: Replication with DRSUAPI_DRS_CRITICAL_ONLY and
     DRSUAPI_DRS_GET_ANC results in WERR_DS_DRA_MISSING_PARENT S
   * BUG 12540: s3:smbd: allow "server min protocol = SMB3_00" to go via "SMB
     2.???" negprot.

o  John Mulligan <jmulligan@nasuni.com>
   * BUG 12542: docs: Improve description of "unix_primary_group" parameter in
     idmap_ad manpage.

o  Andreas Schneider <asn@samba.org>
   * BUG 12552: waf: Do not install the unit test binary for krb5samba.

o  Amitay Isaacs <amitay@gmail.com>
   * BUG 12547: ctdb-build: Install CTDB tests correctly from toplevel.
   * BUG 12549: ctdb-common: ioctl(.. FIONREAD ..) returns an int value.

o  Garming Sam <garming@catalyst.net.nz>
   * BUG 12577: 'samba-tool dbcheck' gives errors on one-way links after a
     rename.

o  Uri Simchoni <uri@samba.org>
   * BUG 12529: waf: Backport finding of pkg-config.


CHANGES SINCE 4.6.0rc1
======================

o  Amitay Isaacs <amitay@gmail.com>
   * BUG 12469: CTDB lock helper getting stuck trying to lock a record.
   * BUG 12500: ctdb-common: Fix a bug in packet reading code for generic socket
     I/O.
   * BUG 12510: sock_daemon_test 4 crashes with SEGV.
   * BUG 12513: ctdb-daemon: Remove stale eventd socket.

o  Björn Jacke <bj@sernet.de>
   * BUG 12535: vfs_default: Unlock the right file in copy chunk.

o  Volker Lendecke <vl@samba.org>
   * BUG 12509: messaging: Fix dead but not cleaned-up-yet destination sockets.
   * BUG 12538: Backport winbind fixes.

o  Stefan Metzmacher <metze@samba.org>
   * BUG 12501: s3:winbindd: talloc_steal the extra_data in
     winbindd_list_users_recv().

o  Martin Schwenke <martin@meltin.net>
   * BUG 12511: ctdb-takeover: Handle case where there are no RELEASE_IPs to
     send.
   * BUG 12512: ctdb-scripts: Fix remaining uses of "ctdb gratiousarp".
   * BUG 12516: ctdb-scripts: /etc/iproute2/rt_tables gets populated with multiple
     'default' entries.


#######################################
Reporting bugs & Development Discussion
#######################################

Please discuss this release on the samba-technical mailing list or by
joining the #samba-technical IRC channel on irc.freenode.net.

If you do report problems then please try to send high quality
feedback. If you don't provide vital information to help us track down
the problem then you will probably be ignored.  All bug reports should
be filed under the Samba 4.1 and newer product in the project's Bugzilla
database (https://bugzilla.samba.org/).


======================================================================
== Our Code, Our Bugs, Our Responsibility.
== The Samba Team
======================================================================