From 31214674545c3703c1171a02a1949a5d3162bdee Mon Sep 17 00:00:00 2001
From: Daniel Golle <daniel@makrotopia.org>
Date: Mon, 19 Oct 2020 13:43:23 +0100
Subject: [PATCH] early: run ubusd non-root as user ubus, group ubus

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
 service/service.c | 7 ++++++-
 service/service.h | 2 +-
 state.c           | 9 ++++++++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/service/service.c b/service/service.c
index cabc69c..b3286dc 100644
--- a/service/service.c
+++ b/service/service.c
@@ -972,7 +972,7 @@ static struct ubus_object main_object = {
 };
 
 int
-service_start_early(char *name, char *cmdline)
+service_start_early(char *name, char *cmdline, char *user, char *group)
 {
 	void *instances, *instance, *command, *respawn;
 	char *t;
@@ -993,6 +993,11 @@ service_start_early(char *name, char *cmdline)
 	blobmsg_add_string(&b, NULL, "1");
 	blobmsg_add_string(&b, NULL, "0");
 	blobmsg_close_array(&b, respawn);
+	if (user)
+		blobmsg_add_string(&b, "user", user);
+	if (group)
+		blobmsg_add_string(&b, "group", group);
+
 	blobmsg_close_table(&b, instance);
 	blobmsg_close_table(&b, instances);
 
diff --git a/service/service.h b/service/service.h
index fac5da9..48157cc 100644
--- a/service/service.h
+++ b/service/service.h
@@ -55,7 +55,7 @@ struct service {
 void service_validate_add(struct service *s, struct blob_attr *attr);
 void service_validate_dump(struct blob_buf *b, struct service *s);
 void service_validate_dump_all(struct blob_buf *b, char *p, char *s);
-int service_start_early(char *name, char *cmdline);
+int service_start_early(char *name, char *cmdline, char *user, char *group);
 void service_stopped(struct service *s);
 void service_validate_del(struct service *s);
 void service_event(const char *type, const char *service, const char *instance);
diff --git a/state.c b/state.c
index e117ea3..6ca1d5e 100644
--- a/state.c
+++ b/state.c
@@ -13,6 +13,7 @@
  */
 
 #include <fcntl.h>
+#include <pwd.h>
 #include <sys/reboot.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -125,6 +126,7 @@ static void perform_halt()
 static void state_enter(void)
 {
 	char ubus_cmd[] = "/sbin/ubusd";
+	struct passwd *p;
 
 	switch (state) {
 	case STATE_EARLY:
@@ -139,8 +141,13 @@ static void state_enter(void)
 		watchdog_init(0);
 		set_stdio("console");
 		LOG("- ubus -\n");
+		p = getpwnam("ubus");
+		if (p) {
+			mkdir(p->pw_dir, 0755);
+			chown(p->pw_dir, p->pw_uid, p->pw_gid);
+		}
 		procd_connect_ubus();
-		service_start_early("ubus", ubus_cmd);
+		service_start_early("ubus", ubus_cmd, p?"ubus":NULL, p?"ubus":NULL);
 		break;
 
 	case STATE_INIT:
-- 
2.30.2