docs: add v2021.1.2 release notes (#2488)

docs/releases/index.rst

@@ -5,6 +5,7 @@ Release Notes
    :caption: Gluon 2021.1
    :maxdepth: 2
 
+   v2021.1.2
    v2021.1.1
    v2021.1
 

docs/releases/v2021.1.2.rst

+Gluon 2021.1.2 (unreleased)
+===========================
+
+Important notes
+---------------
+
+Upgrades to v2021.1 and later releases are only supported from releases v2018.2
+and later. Migration code for upgrades from older versions has been removed to
+simplify maintenance.
+
+
+Updates
+-------
+
+- The Linux kernel was updated to version 4.14.275
+- The mac80211 wireless driver stack was updated to a version based on kernel
+  4.19.237
+
+Various minor package updates are not listed here and can be found in the commit
+log.
+
+
+Bugfixes
+--------
+
+* **[SECURITY]** This release will fix a critical security vulnerability
+
+  This bugfix has not been pushed to the public Gluon repository yet to avoid
+  disclosing information on the issue. A detailed advisory will be published at
+  the same time as the Gluon release.
+
+* **[SECURITY]** Config Mode: Prevent Cross-Site Request Forgery (CSRF)
+
+  The Config Mode was not validating the *Origin* header of POST requests.
+  This allowed arbitrary websites to modify   configuration (including SSH keys)
+  on a Gluon node in Config Mode reachable from a user's browser by sending POST
+  requests with form data to 192.168.1.1.
+
+  The impact of this issue is considered low, as nodes are only vulnerable while
+  in Config Mode.
+
+* Config Mode: Fix occasionally hanging page load after submitting the
+  configuration wizard causing the reboot message and VPN key not to be
+  displayed
+
+* Config Mode (OSM): Update default OpenLayers source URL
+
+  The OSM feature of the Config Mode was broken when the default source URL was
+  used for OpenLayers, as the old URL has become unavailable. The default was
+  updated to a URL that should not become unavailable again.
+
+* Config Mode (OSM): Fix error when using ``"`` character in attribution text
+
+* respondd-module-airtime: Fix respondd crash on devices with disabled WLAN
+  interfaces
+
+  Several improvements were made to the error handling of the
+  *respondd-module-airtime* package. The "PHY ID" field (introduced in Gluon
+  2021.1) was removed again.
+
+* ipq40xx: Fix bad WLAN performance on Plasma Cloud PA1200 and PA2200 devices
+
+* Fix occasional build failure in "perl" package with high number of threads
+  (``-j32`` or higher)
+
+
+Other improvements
+------------------
+
+* Several improvements were made to the status page:
+
+  - WLAN channel display does not require the *respondd-module-airtime* package
+    anymore
+  - The "gateway nexthop" label now links to the status page of the nexthop node
+  - The timeout to retrieve information from neighbour nodes was increased,
+    making the display of the name
+    of overloaded, slow or otherwise badly reachable nodes more likely to
+    succeed
+
+
+Known issues
+------------
+
+* Upgrading EdgeRouter-X from versions before v2020.1.x may lead to a
+  soft-bricked state due to bad blocks on the NAND flash which the NAND driver
+  before this release does not handle well.
+  (`#1937 <https://github.com/freifunk-gluon/gluon/issues/1937>`_)
+
+* The integration of the BATMAN_V routing algorithm is incomplete.
+
+  - Mesh neighbors don't appear on the status page.
+    (`#1726 <https://github.com/freifunk-gluon/gluon/issues/1726>`_)
+    Many tools have the BATMAN_IV metric hardcoded, these need to be updated to
+    account for the new throughput metric.
+  - Throughput values are not correctly acquired for different interface types.
+    (`#1728 <https://github.com/freifunk-gluon/gluon/issues/1728>`_)
+    This affects virtual interface types like bridges and VXLAN.
+
+* Default TX power on many Ubiquiti devices is too high, correct offsets are
+  unknown (`#94 <https://github.com/freifunk-gluon/gluon/issues/94>`_)
+
+  Reducing the TX power in the Advanced Settings is recommended.
+
+* In configurations without VXLAN, the MAC address of the WAN interface is
+  modified even when Mesh-on-WAN is disabled
+  (`#496 <https://github.com/freifunk-gluon/gluon/issues/496>`_)
+
+  This may lead to issues in environments where a fixed MAC address is expected
+  (like VMware when promiscuous mode is disallowed).