Backport of Correct Default for MaximumPageSize into release/1.12.x

changelog/20453.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+auth/ldap: Set default value for `max_page_size` properly
+```

sdk/helper/ldaputil/client.go

@@ -536,7 +536,7 @@ func (c *Client) GetLdapGroups(cfg *ConfigEntry, conn Connection, userDN string,
 	if cfg.UseTokenGroups {
 		entries, err = c.performLdapTokenGroupsSearch(cfg, conn, userDN)
 	} else {
-		if paging, ok := conn.(PagingConnection); ok && cfg.MaximumPageSize >= 0 {
+		if paging, ok := conn.(PagingConnection); ok && cfg.MaximumPageSize > 0 {
 			entries, err = c.performLdapFilterGroupsSearchPaging(cfg, paging, userDN, username)
 		} else {
 			entries, err = c.performLdapFilterGroupsSearch(cfg, conn, userDN, username)

sdk/helper/ldaputil/config.go

@@ -6,7 +6,6 @@ import (
 	"encoding/pem"
 	"errors"
 	"fmt"
-	"math"
 	"strings"
 	"text/template"
 
@@ -236,8 +235,8 @@ Default: ({{.UserAttr}}={{.Username}})`,
 
 		"max_page_size": {
 			Type:        framework.TypeInt,
-			Description: "The maximum number of results to return for a single paged query. If not set, the server default will be used for paged searches. A requested max_page_size of 0 is interpreted as no limit by LDAP servers. If set to a negative value, search requests will not be paged.",
-			Default:     math.MaxInt32,
+			Description: "If set to a value greater than 0, the LDAP backend will use the LDAP server's paged search control to request pages of up to the given size. This can be used to avoid hitting the LDAP server's maximum result size limit. Otherwise, the LDAP backend will not use the paged search control.",
+			Default:     0,
 		},
 	}
 }

sdk/helper/ldaputil/config_test.go

@@ -171,7 +171,7 @@ var jsonConfigDefault = []byte(`
   "username_as_alias": false,
   "request_timeout": 90,
   "connection_timeout": 30,
-  "max_page_size": 2147483647,
+  "max_page_size": 0,
   "CaseSensitiveNames": false,
   "ClientTLSCert": "",
   "ClientTLSKey": ""

website/content/api-docs/auth/ldap.mdx

@@ -94,11 +94,10 @@ This endpoint configures the LDAP auth method.
   returning _user_ objects, use: `memberOf`. The default is `cn`.
 - `username_as_alias` `(bool: false)` - If set to true, forces the auth method
   to use the username passed by the user as the alias name.
-- `max_page_size` `(int: math.MaxInt32)` - If set to a value greater than 0, the LDAP
+- `max_page_size` `(int: 0)` - If set to a value greater than 0, the LDAP
   backend will use the LDAP server's paged search control to request pages of
   up to the given size. This can be used to avoid hitting the LDAP server's
-  maximum result size limit. A value of 0 will be interpreted by the LDAP
-  server as unlimited. If set to -1, the LDAP backend will not use the
+  maximum result size limit. Otherwise, the LDAP backend will not use the
   paged search control.
 
 @include 'tokenfields.mdx'

website/content/docs/auth/ldap.mdx

@@ -152,7 +152,7 @@ Use `vault path-help` for more details.
 ### Other
 
 - `username_as_alias` (bool, optional) - If set to true, forces the auth method to use the username passed by the user as the alias name.
-- `max_page_size` (int, optional) - The maximum number of results to return for a single LDAP query. This is useful for preventing large queries from being run against the LDAP server. The default is the maximum value for an int32.
+- `max_page_size` (int, optional) - If set to a value greater than 0, the LDAP backend will use the LDAP server's paged search control to request pages of up to the given size. This can be used to avoid hitting the LDAP server's maximum result size limit. Otherwise, the LDAP backend will not use the paged search control.
 
 ## Examples:
 

website/content/docs/upgrading/upgrade-to-1.11.x.mdx

@@ -27,4 +27,19 @@ API path by setting the [bool config option](/api-docs/secret/databases/elasticd
 
 @include 'raft-retry-join-failure.mdx'
 
-@include 'tokenization-rotation-persistence.mdx'
+@include 'tokenization-rotation-persistence.mdx'
+
+### LDAP Pagination Issue
+
+There was a regression introduced in 1.11.10 relating to LDAP maximum page sizes, resulting in
+an error `no LDAP groups found in groupDN [...] only policies from locally-defined groups available`.  The issue
+occurs when upgrading Vault with an instance that has an existing LDAP Auth configuration.
+
+As a workaround, disable paged searching using the following:
+```shell-session
+vault write auth/ldap/config max_page_size=-1
+```
+
+#### Impacted Versions
+
+Affects Vault 1.11.10.

website/content/docs/upgrading/upgrade-to-1.12.x.mdx

@@ -152,7 +152,7 @@ It will produce errors in Vault Server's logs such as:
   error=
   | 1 error occurred:
   | 	* panic generating audit log
-  | 
+  |
 ```
 
 As a workaround, [listing plugins by type](/api-docs/system/plugins-catalog#list-plugins-1)
@@ -184,3 +184,18 @@ Affects version 1.12.3. A fix will be released in 1.12.4.
 @include 'tokenization-rotation-persistence.mdx'
 
 @include 'ocsp-redirect.mdx'
+
+### LDAP Pagination Issue
+
+There was a regression introduced in 1.12.6 relating to LDAP maximum page sizes, resulting in
+an error `no LDAP groups found in groupDN [...] only policies from locally-defined groups available`.  The issue
+occurs when upgrading Vault with an instance that has an existing LDAP Auth configuration.
+
+As a workaround, disable paged searching using the following:
+```shell-session
+vault write auth/ldap/config max_page_size=-1
+```
+
+#### Impacted Versions
+
+Affects Vault 1.12.6.