First-draft release notes for 18.3.

As usual, the release notes for other branches will be made by cutting
these down, but put them up for community review first.

diff --git a/doc/src/sgml/release-18.sgml b/doc/src/sgml/release-18.sgml
index 923001f0a55e08dbb86d32fc95822b4cc90a2528..e952716b5eb642f8e4d53977696bee259d5ce0ad 100644 (file)
--- a/doc/src/sgml/release-18.sgml
+++ b/doc/src/sgml/release-18.sgml
@@ -1,6 +1,262 @@
 <!-- doc/src/sgml/release-18.sgml -->
 <!-- See header comment in release.sgml about typical markup -->
 
+ <sect1 id="release-18-3">
+  <title>Release 18.3</title>
+
+  <formalpara>
+  <title>Release date:</title>
+  <para>2026-02-26</para>
+  </formalpara>
+
+  <para>
+   This release contains a small number of fixes from 18.2.
+   For information about new features in major release 18, see
+   <xref linkend="release-18"/>.
+  </para>
+
+  <sect2 id="release-18-3-migration">
+   <title>Migration to Version 18.3</title>
+
+   <para>
+    A dump/restore is not required for those running 18.X.
+   </para>
+
+   <para>
+    However, if you are upgrading from a version earlier than 18.2,
+    see <xref linkend="release-18-2"/>.
+   </para>
+  </sect2>
+
+  <sect2 id="release-18-3-changes">
+   <title>Changes</title>
+
+   <itemizedlist>
+
+    <listitem>
+<!--
+Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
+Branch: REL_18_STABLE [817f74600] 2026-02-16 17:16:59 +0200
+Branch: REL_17_STABLE [4a36c89f1] 2026-02-16 17:18:17 +0200
+Branch: REL_16_STABLE [23064542f] 2026-02-16 17:20:29 +0200
+Branch: REL_15_STABLE [899de38d8] 2026-02-16 17:20:51 +0200
+Branch: REL_14_STABLE [547a8aaa7] 2026-02-16 17:20:56 +0200
+-->
+     <para>
+      Fix failure after replaying a multixid truncation record from WAL
+      that was generated by an older minor version (Heikki Linnakangas)
+      <ulink url="&commit_baseurl;817f74600">&sect;</ulink>
+     </para>
+
+     <para>
+      Erroneous logic for coping with the way that previous versions
+      handled multixid wraparound led to replay failure, with messages
+      like <quote>could not access status of transaction</quote>.
+      A typical scenario in which this could occur is a standby server of
+      the latest minor version consuming WAL from a primary server of an
+      older version.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Noah Misch <noah@leadboat.com>
+Branch: master [9f4fd119b] 2026-02-14 12:16:16 -0800
+Branch: REL_18_STABLE [6e045e1a6] 2026-02-14 12:16:19 -0800
+Branch: REL_17_STABLE [5d5232bc3] 2026-02-14 12:16:20 -0800
+Branch: REL_16_STABLE [bdfb37228] 2026-02-14 12:16:20 -0800
+Branch: REL_15_STABLE [a20eb248c] 2026-02-14 12:16:21 -0800
+Branch: REL_14_STABLE [14b1fd617] 2026-02-14 12:16:21 -0800
+Branch: master [8cef93d8a] 2026-02-16 18:04:58 -0800
+Branch: REL_18_STABLE [d04b34d68] 2026-02-16 18:05:01 -0800
+Branch: REL_17_STABLE [50d361f62] 2026-02-16 18:05:02 -0800
+Branch: REL_16_STABLE [2280ab354] 2026-02-16 18:05:02 -0800
+Branch: REL_15_STABLE [ec86152e0] 2026-02-16 18:05:02 -0800
+Branch: REL_14_STABLE [a0769e74d] 2026-02-16 18:05:03 -0800
+Branch: master [4644f8b23] 2026-02-14 12:16:16 -0800
+Branch: REL_18_STABLE [4174e41b9] 2026-02-14 12:16:19 -0800
+Branch: REL_17_STABLE [8e73530f1] 2026-02-14 12:16:20 -0800
+Branch: REL_16_STABLE [45eb47230] 2026-02-14 12:16:20 -0800
+Branch: REL_15_STABLE [5b305ebcc] 2026-02-14 12:16:20 -0800
+Branch: REL_14_STABLE [44fc85bbf] 2026-02-14 12:16:21 -0800
+-->
+     <para>
+      Avoid incorrect complaint of invalid encoding
+      when <function>substring()</function> is applied
+      to <quote>toasted</quote> data (Noah Misch)
+      <ulink url="&commit_baseurl;6e045e1a6">&sect;</ulink>
+      <ulink url="&commit_baseurl;d04b34d68">&sect;</ulink>
+      <ulink url="&commit_baseurl;4174e41b9">&sect;</ulink>
+     </para>
+
+     <para>
+      The fix for CVE-2026-2006 was too aggressive and could raise an
+      error about an incomplete character in cases that are actually
+      valid.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
+Branch: master [18bcdb75d] 2026-02-20 11:56:42 +0200
+Branch: REL_18_STABLE [041e02e6a] 2026-02-20 11:56:50 +0200
+-->
+     <para>
+      Fix oversight in the fix for CVE-2026-2007 (Zsolt Parragi)
+      <ulink url="&commit_baseurl;041e02e6a">&sect;</ulink>
+     </para>
+
+     <para>
+      If the <quote>bounds</quote> array needed to be expanded, because
+      the input contained more trigrams than the initial guess,
+      <function>generate_trgm_only</function> didn't return the modified
+      array pointer to its caller.  That would lead to incorrect output
+      from <function>strict_word_similarity()</function> and related
+      functions, or in rare cases a crash.  The faulty code is reached if
+      the input string becomes longer when it's converted to lower case.
+      The only known instances of that occur when an ICU locale is used
+      with certain single-byte encodings.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Tom Lane <tgl@sss.pgh.pa.us>
+Branch: master [759b03b24] 2026-02-18 14:14:44 -0500
+Author: Andrew Dunstan <andrew@dunslane.net>
+Branch: REL_18_STABLE [2f6ee7b38] 2026-02-18 10:31:03 -0500
+-->
+     <para>
+      Fix the volatility marking
+      of <function>json_strip_nulls()</function>
+      and <function>jsonb_strip_nulls()</function> (Andrew Dunstan)
+      <ulink url="&commit_baseurl;2f6ee7b38">&sect;</ulink>
+     </para>
+
+     <para>
+      These functions have always been considered immutable, but
+      refactoring in version 18 accidentally marked them stable instead.
+      That prevents their use in index expressions and could cause
+      unnecessary repeat evaluations in queries.  This fix corrects the
+      marking in newly-initialized database clusters (including clusters
+      that are <application>pg_upgrade</application>'d to 18.3 or later).
+      However it will not help existing clusters made using 18.0 through
+      18.2.
+     </para>
+
+     <para>
+      If this mistake affects your usage of these functions, the
+      recommended fix for an existing cluster is a manual catalog update.
+      As superuser, perform
+<programlisting>
+UPDATE pg_catalog.pg_proc SET provolatile = 'i' WHERE oid IN ('3261','3262');
+</programlisting>
+      in each affected database.  Update <literal>template0</literal>
+      and <literal>template1</literal> as well, so that databases made in
+      future will have the fix.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Richard Guo <rguo@postgresql.org>
+Branch: master [691977d37] 2026-02-20 17:57:53 +0900
+Branch: REL_18_STABLE [ed57c207c] 2026-02-20 18:00:02 +0900
+Branch: REL_17_STABLE [bcaf1b510] 2026-02-20 18:01:56 +0900
+Branch: REL_16_STABLE [ec20a4552] 2026-02-20 18:04:26 +0900
+-->
+     <para>
+      Fix computation of the set of potentially-nulling outer joins for
+      the output of a <literal>LATERAL UNION ALL</literal> subquery
+      (Richard Guo)
+      <ulink url="&commit_baseurl;ed57c207c">&sect;</ulink>
+     </para>
+
+     <para>
+      This error could lead to skipping <literal>NOT NULL</literal> tests
+      in the mistaken belief that they were unnecessary, resulting in
+      wrong query output.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
+Branch: master [78a5e3074] 2026-02-11 18:50:57 +0200
+Branch: REL_18_STABLE [53463b4b2] 2026-02-11 18:51:06 +0200
+Branch: REL_17_STABLE [842473337] 2026-02-11 18:51:12 +0200
+Branch: REL_16_STABLE [2332911ae] 2026-02-11 18:51:19 +0200
+Branch: REL_15_STABLE [ebc53ca7b] 2026-02-11 18:51:25 +0200
+Branch: REL_14_STABLE [82b495cdd] 2026-02-11 18:51:32 +0200
+-->
+     <para>
+      Fix <function>pg_stat_get_backend_wait_event()</function>
+      and <function>pg_stat_get_backend_wait_event_type()</function>
+      to report values for auxiliary processes (Heikki Linnakangas)
+      <ulink url="&commit_baseurl;53463b4b2">&sect;</ulink>
+     </para>
+
+     <para>
+      Previously these functions returned NULL for auxiliary processes,
+      but that's inconsistent with
+      the <structname>pg_stat_activity</structname> view.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Tom Lane <tgl@sss.pgh.pa.us>
+Branch: master [9863c9075] 2026-02-11 16:53:14 -0500
+Branch: REL_18_STABLE [ce4b7e3a1] 2026-02-11 16:53:14 -0500
+Branch: REL_17_STABLE [dfd850980] 2026-02-11 16:53:14 -0500
+Branch: REL_16_STABLE [c66f4cff1] 2026-02-11 16:53:14 -0500
+Branch: REL_15_STABLE [254b15cbf] 2026-02-11 16:53:14 -0500
+Branch: REL_14_STABLE [2b93d3820] 2026-02-11 16:53:14 -0500
+-->
+     <para>
+      Fix casting a composite-type variable to a domain type when
+      returning its value from a PL/pgSQL function (Tom Lane)
+      <ulink url="&commit_baseurl;ce4b7e3a1">&sect;</ulink>
+     </para>
+
+     <para>
+      If the variable's value is NULL, a <quote>cache lookup failed for
+      type 0</quote> error resulted.
+     </para>
+    </listitem>
+
+    <listitem>
+<!--
+Author: Michael Paquier <michael@paquier.xyz>
+Branch: master [a6f823e77] 2026-02-17 08:41:26 +0900
+Branch: REL_18_STABLE [4a0843c53] 2026-02-17 08:41:30 +0900
+Branch: REL_17_STABLE [0dfbe42da] 2026-02-17 08:41:32 +0900
+Branch: REL_16_STABLE [31d0b917d] 2026-02-17 08:41:34 +0900
+Branch: REL_15_STABLE [63c05e03b] 2026-02-17 08:41:35 +0900
+Branch: REL_14_STABLE [f604cc695] 2026-02-17 08:41:37 +0900
+-->
+     <para>
+      Fix potential null pointer dereference
+      in <filename>contrib/hstore</filename>'s binary input function
+      (Michael Paquier)
+      <ulink url="&commit_baseurl;4a0843c53">&sect;</ulink>
+     </para>
+
+     <para>
+      <type>hstore</type>'s receive function crashed on input containing
+      duplicate keys.  <type>hstore</type> values generated by Postgres
+      would never contain duplicate keys, so this mistake has gone
+      unnoticed.  The crash could be provoked by malicious or corrupted
+      data.
+     </para>
+    </listitem>
+
+   </itemizedlist>
+
+  </sect2>
+ </sect1>
+
  <sect1 id="release-18-2">
   <title>Release 18.2</title>