2 files changed, 83 insertions, 0 deletions

diff --git a/meta/recipes-connectivity/dhcpcd/dhcpcd_9.4.1.bb b/meta/recipes-connectivity/dhcpcd/dhcpcd_9.4.1.bb
index ab6ffe986c..1d03de09c8 100644
--- a/meta/recipes-connectivity/dhcpcd/dhcpcd_9.4.1.bb
+++ b/meta/recipes-connectivity/dhcpcd/dhcpcd_9.4.1.bb
@@ -13,6 +13,7 @@ UPSTREAM_CHECK_URI = "https://roy.marples.name/downloads/dhcpcd/"
 
 SRC_URI = "https://roy.marples.name/downloads/${BPN}/${BPN}-${PV}.tar.xz \
            file://0001-remove-INCLUDEDIR-to-prevent-build-issues.patch \
+           file://0001-20-resolv.conf-improve-the-sitation-of-working-with-.patch \
            file://dhcpcd.service \
            file://dhcpcd@.service \
            "
diff --git a/meta/recipes-connectivity/dhcpcd/files/0001-20-resolv.conf-improve-the-sitation-of-working-with-.patch b/meta/recipes-connectivity/dhcpcd/files/0001-20-resolv.conf-improve-the-sitation-of-working-with-.patch
new file mode 100644
index 0000000000..6f90c88249
--- /dev/null
+++ b/meta/recipes-connectivity/dhcpcd/files/0001-20-resolv.conf-improve-the-sitation-of-working-with-.patch
@@ -0,0 +1,82 @@
+From 02acc4d875ee81e6fd19ef66d69c9f55b4b4a7e7 Mon Sep 17 00:00:00 2001
+From: Chen Qi <Qi.Chen@windriver.com>
+Date: Wed, 9 Nov 2022 16:33:18 +0800
+Subject: [PATCH] 20-resolv.conf: improve the sitation of working with systemd
+
+systemd's resolvconf implementation ignores the protocol part.
+See https://github.com/systemd/systemd/issues/25032.
+
+When using 'dhcp server + dns server + dhcpcd + systemd', we
+get an integration issue, that is dhcpcd runs 'resolvconf -d eth0.ra',
+yet systemd's resolvconf treats it as eth0. This will delete the
+DNS information set by 'resolvconf -a eth0.dhcp'.
+
+Fortunately, 20-resolv.conf has the ability to build the resolv.conf
+file contents itself. We can just pass the generated contents to
+systemd's resolvconf. This way, the DNS information is not incorrectly
+deleted. Also, it does not cause behavior regression for dhcpcd
+in other cases.
+
+Upstream-Status: Inappropriate [OE Specific]
+This patch has been rejected by dhcpcd upstream.
+See details in https://github.com/NetworkConfiguration/dhcpcd/pull/152
+
+Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
+---
+ hooks/20-resolv.conf | 17 +++++++++++++----
+ 1 file changed, 13 insertions(+), 4 deletions(-)
+
+diff --git a/hooks/20-resolv.conf b/hooks/20-resolv.conf
+index 504a6c53..eb6e5845 100644
+--- a/hooks/20-resolv.conf
++++ b/hooks/20-resolv.conf
+@@ -11,8 +11,12 @@ nocarrier_roaming_dir="$state_dir/roaming"
+ NL="
+ "
+ : ${resolvconf:=resolvconf}
++resolvconf_from_systemd=false
+ if type "$resolvconf" >/dev/null 2>&1; then
+        have_resolvconf=true
++       if [ $(basename $(readlink -f $(which $resolvconf))) = resolvectl ]; then
++               resolvconf_from_systemd=true
++       fi
+ else
+        have_resolvconf=false
+ fi
+@@ -69,8 +73,13 @@ build_resolv_conf()
+        else
+                echo "# /etc/resolv.conf.tail can replace this line" >> "$cf"
+        fi
+-       if change_file /etc/resolv.conf "$cf"; then
+-               chmod 644 /etc/resolv.conf
++       if $resolvconf_from_systemd; then
++               [ -n "$ifmetric" ] && export IF_METRIC="$ifmetric"
++               "$resolvconf" -a "$ifname" <"$cf"
++       else
++               if change_file /etc/resolv.conf "$cf"; then
++                       chmod 644 /etc/resolv.conf
++               fi
+        fi
+        rm -f "$cf"
+ }
+@@ -170,7 +179,7 @@ add_resolv_conf()
+        for x in ${new_domain_name_servers}; do
+                conf="${conf}nameserver $x$NL"
+        done
+-       if $have_resolvconf; then
++       if $have_resolvconf && ! $resolvconf_from_systemd; then
+                [ -n "$ifmetric" ] && export IF_METRIC="$ifmetric"
+                printf %s "$conf" | "$resolvconf" -a "$ifname"
+                return $?
+@@ -186,7 +195,7 @@ add_resolv_conf()
+ 
+ remove_resolv_conf()
+ {
+-       if $have_resolvconf; then
++       if $have_resolvconf && ($if_down || ! $resolvconf_from_systemd); then
+                "$resolvconf" -d "$ifname" -f
+        else
+                if [ -e "$resolv_conf_dir/$ifname" ]; then
+-- 
+2.17.1
+