Add LWIP RIO patch to patch dir. (#12623)

* Add LWIP RIO patch to patch dir.

Also readme

* Canadian -> US spelling + function names.

* Added extra  works in wordlist, removed duplicates (that differed by case), resorted

* Actually remove wordlist duplicates

* Add forgotten words

Co-authored-by: Andrei Litvin <andy314@gmail.com>

.github/.wordlist.txt

@@ -29,7 +29,6 @@ aef
 AES
 algs
 alloc
-ameba
 Ameba
 amebad
 amebaiot
@@ -88,7 +87,6 @@ BeagleBone
 befc
 bitbake
 bld
-ble
 BLE
 BleApplicationDelegate
 BleLayer
@@ -160,7 +158,6 @@ CHIPTest
 CHIPTool
 chmod
 chrpath
-cipd
 CIPD
 CircleCI
 cJTAG
@@ -331,7 +328,6 @@ ee
 EEE
 eef
 ef
-efr
 EFR
 eg
 EjQ
@@ -347,6 +343,7 @@ eno
 entrypoint
 enum
 env
+eq
 esd
 ESPPORT
 Espressif
@@ -390,7 +387,6 @@ flashdebug
 focusable
 forkpty
 formatOnSave
-fota
 FOTA
 FreeRTOS
 FreeRTOSConfig
@@ -421,7 +417,6 @@ gn
 GND
 gni
 GNinja
-gnuarmemb
 GNUARMEMB
 gnueabihf
 googleapis
@@ -463,7 +458,6 @@ ifdef
 ifdefs
 IGMP
 ihex
-im
 IM
 imager
 imagetool
@@ -501,7 +495,6 @@ itemName
 iterable
 JDK
 jinja
-jlink
 JLink
 JLinkExe
 JLinkRTTClient
@@ -654,6 +647,7 @@ navpad
 ncs
 nding
 NDK
+netcmp
 netif
 netplan
 NetworkCommissioning
@@ -856,12 +850,11 @@ ScriptBinding
 SDC
 SDHC
 SDK
-SDK's
 sdkconfig
+SDK's
 SDKs
 SDKTARGETSYSROOT
 sdl
-segger
 SEGGER
 semver
 sendto
@@ -932,7 +925,6 @@ sysconfdir
 SysConfig
 sysctl
 sysdeps
-sysroot
 SYSROOT
 systemctl
 systemd
@@ -992,7 +984,6 @@ ttyUSB
 TvChannel
 TXD
 txt
-uart
 UART
 udhcpc
 UDP
@@ -1001,7 +992,6 @@ udpPort
 ug
 ui
 uint
-unblur
 UNBLUR
 uncommissioned
 unfocus

src/lwip/patches/README.md

@@ -0,0 +1,41 @@
+# LwIP patches
+
+This directory contains patch files for LwIP that enable required or desired
+functionality in Matter. Patches that are not yet integrated into mainline LwIP
+are provided as a patch file. This file also contains a list of helpful patches
+that may not be present in vendor forks of the LwIP codebase
+
+## Un-merged patches
+
+### Route information options (RIO)
+
+Required for wifi devices to support communication with a thread device behind
+an open thread border router.
+
+- patch file: rio_patch_updated.patch
+- savannah link: https://savannah.nongnu.org/patch/?10114
+
+Troubleshooting: The patch uses the `ip6_addr_net_eq` function, which is a
+recent API change on upstream LwIP. The previous version of this function is
+`ip6_addr_netcmp`, so this function call may need to be replaced on older forks.
+
+## Important upstream patches
+
+### Malformed neighbor solicitation packet fix
+
+- issue raised here
+ https://github.com/project-chip/connectedhomeip/issues/9791
+- fixed in matter fork by
+ https://github.com/project-chip/connectedhomeip/pull/10160
+- fixed in upstream by
+ https://git.savannah.nongnu.org/cgit/lwip.git/commit/?id=bc08c1d2b79b4763fc0f8f0bf0ed58e0c2899b3a
+
+### DHCPv6 DNS bug
+
+There was a bug in the DHCPv6 code where if the router sent a DNS using DHCPv6
+stateless, it would set the DNS server as an ipv4 address, which ended up being
+garbage. This would invalidate the whole DNS table, and lwip does not have a
+default backup.
+
+- fixed in upstream here:
+ https://git.savannah.nongnu.org/cgit/lwip.git/commit/?id=941300c21c45a4dbf1c074b29a9ca3c88c9f6553