Fiz sizeof() confusion in 527c3c7d0d

When destroying the UBus context, private fields of our ubus_object were
being reset to 0 while UBus was still owning those objects. While this
seems to work out fine, it seems cleaner to first release the object so
that UBus no longer owns it, before proceding to reset those fields.

Signed-off-by: Etan Kissling <etan.kissling@gmail.com>

CHANGELOG

@@ -1,6 +1,6 @@
 version 2.86
 	Handle DHCPREBIND requests in the DHCPv6 server code.
-	Thanks to Aichun Li for spotting this ommision, and the initial
+	Thanks to Aichun Li for spotting this omission, and the initial
 	patch.
 
 	Fix bug which caused dnsmasq to lose track of processes forked
@@ -33,7 +33,7 @@ version 2.86
 	address=/example.com/1.2.3.4
 	address=/example.com/5.6.7.8
 	It also handles multiple upstream servers for a domain better; using
-	the same try/retry alogrithms as non domain-specific servers. This
+	the same try/retry algorithms as non domain-specific servers. This
 	also applies to DNSSEC-generated queries.
 	Finally, some of the oldest and gnarliest code in dnsmasq has had
 	a significant clean-up. It's far from perfect, but it _is_ better.
@@ -76,12 +76,16 @@ version 2.86
 	Disallowed queries are not forwarded; they are rejected
 	with a REFUSED error code.
 
-	Allow smaller then 64 prefix lengths in synth-domain, with caveats.
+	Allow smaller than 64 prefix lengths in synth-domain, with caveats.
 	--synth-domain=1234:4567::/56,example.com is now valid.
 
 	Make domains generated by --synth-domain appear in replies
 	when in authoritative mode.
 
+	Ensure CAP_NET_ADMIN capability is available when
+	conntrack is configured. Thanks to Yick Xie for spotting
+	the lack of this.
+
 	
 version 2.85
         Fix problem with DNS retries in 2.83/2.84.

contrib/lease-tools/dhcp_lease_time.c

@@ -153,7 +153,11 @@ int main(int argc, char **argv)
       exit(1);
     }
  
-  lease.s_addr = inet_addr(argv[1]);
+  if (inet_pton(AF_INET, argv[1], &lease) < 1)
+    {
+      fprintf(stderr, "invalid address: %s\n", argv[1]);
+      exit(1);
+    }
    
   memset(&packet, 0, sizeof(packet));
  
@@ -177,7 +181,7 @@ int main(int argc, char **argv)
   *(p++) = OPTION_END;
  
   dest.sin_family = AF_INET;
-  dest.sin_addr.s_addr = inet_addr("127.0.0.1");
+  (void)inet_pton(AF_INET, "127.0.0.1", &dest.sin_addr);
   dest.sin_port = ntohs(DHCP_SERVER_PORT);
   
   if (sendto(fd, &packet, sizeof(packet), 0, 

contrib/lease-tools/dhcp_release.c

@@ -288,13 +288,12 @@ int main(int argc, char **argv)
       exit(1);
     }
   
-  if (inet_addr(argv[2]) == INADDR_NONE)
+  if (inet_pton(AF_INET, argv[2], &lease.s_addr) < 1)
     {
       perror("invalid ip address");
       exit(1);
     }
   
-  lease.s_addr = inet_addr(argv[2]);
   server = find_interface(lease, nl, if_nametoindex(argv[1]), fd, &ifr);
   
   memset(&packet, 0, sizeof(packet));

src/dhcp.c

@@ -468,8 +468,11 @@ void dhcp_packet(time_t now, int pxe_fd)
 
   /* This can fail when, eg, iptables DROPS destination 255.255.255.255 */
   if (errno != 0)
+    {
+      inet_ntop(AF_INET, &dest.sin_addr, daemon->addrbuff, ADDRSTRLEN);
       my_syslog(MS_DHCP | LOG_WARNING, _("Error sending DHCP packet to %s: %s"),
-	      inet_ntoa(dest.sin_addr), strerror(errno));
+		daemon->addrbuff, strerror(errno));
+    }
 }
 
 /* check against secondary interface addresses */
@@ -521,10 +524,11 @@ static void guess_range_netmask(struct in_addr addr, struct in_addr netmask)
 	    !(is_same_net(addr, context->start, netmask) &&
 	      is_same_net(addr, context->end, netmask)))
 	  {
-	    strcpy(daemon->dhcp_buff, inet_ntoa(context->start));
+	    inet_ntop(AF_INET, &context->start, daemon->dhcp_buff, DHCP_BUFF_SZ);
-	    strcpy(daemon->dhcp_buff2, inet_ntoa(context->end));
+	    inet_ntop(AF_INET, &context->end, daemon->dhcp_buff2, DHCP_BUFF_SZ);
+	    inet_ntop(AF_INET, &netmask, daemon->addrbuff, ADDRSTRLEN);
 	    my_syslog(MS_DHCP | LOG_WARNING, _("DHCP range %s -- %s is not consistent with netmask %s"),
-		      daemon->dhcp_buff, daemon->dhcp_buff2, inet_ntoa(netmask));
+		      daemon->dhcp_buff, daemon->dhcp_buff2, daemon->addrbuff);
 	  }	
 	context->netmask = netmask;
       }
@@ -922,7 +926,7 @@ void dhcp_read_ethers(void)
       
       if (!*cp)
 	{
-	  if ((addr.s_addr = inet_addr(ip)) == (in_addr_t)-1)
+	  if (inet_pton(AF_INET, ip, &addr.s_addr) < 1)
 	    {
 	      my_syslog(MS_DHCP | LOG_ERR, _("bad address at %s line %d"), ETHERSFILE, lineno); 
 	      continue;
@@ -1097,7 +1101,8 @@ static int  relay_upstream4(struct dhcp_relay *relay, struct dhcp_packet *mess,
       if (option_bool(OPT_LOG_OPTS))
 	{
 	  inet_ntop(AF_INET, &relay->local, daemon->addrbuff, ADDRSTRLEN);
-	  my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay %s -> %s"), daemon->addrbuff, inet_ntoa(relay->server.addr4));
+	  inet_ntop(AF_INET, &relay->server.addr4, daemon->dhcp_buff2, DHCP_BUFF_SZ);
+	  my_syslog(MS_DHCP | LOG_INFO, _("DHCP relay %s -> %s"), daemon->addrbuff, daemon->dhcp_buff2);
 	}
       
       /* Save this for replies */

src/dnsmasq.c

@@ -109,7 +109,6 @@ int main (int argc, char **argv)
   daemon->packet_buff_sz = daemon->edns_pktsz + MAXDNAME + RRFIXEDSZ;
   daemon->packet = safe_malloc(daemon->packet_buff_sz);
   
-  daemon->addrbuff = safe_malloc(ADDRSTRLEN);
   if (option_bool(OPT_EXTRALOG))
     daemon->addrbuff2 = safe_malloc(ADDRSTRLEN);
   
@@ -212,8 +211,13 @@ int main (int argc, char **argv)
 #endif
 
 #ifdef HAVE_CONNTRACK
-  if (option_bool(OPT_CONNTRACK) && (daemon->query_port != 0 || daemon->osport))
+  if (option_bool(OPT_CONNTRACK))
+    {
+      if (daemon->query_port != 0 || daemon->osport)
 	die (_("cannot use --conntrack AND --query-port"), NULL, EC_BADCONF);
+
+      need_cap_net_admin = 1;
+    }
 #else
   if (option_bool(OPT_CONNTRACK))
     die(_("conntrack support not available: set HAVE_CONNTRACK in src/config.h"), NULL, EC_BADCONF);

src/forward.c

@@ -255,29 +255,25 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
   /* new query */
   if (!forward)
     {
-      /* new query */
+      if (lookup_domain(daemon->namebuff, gotname, &first, &last))
+	flags = is_local_answer(now, first, daemon->namebuff);
+      else
+	{
+	  /* no available server. */
+	  ede = EDE_NOT_READY;
+	  flags = 0;
+	}
        
       /* don't forward A or AAAA queries for simple names, except the empty name */
-      if (option_bool(OPT_NODOTS_LOCAL) &&
+      if (!flags &&
+	  option_bool(OPT_NODOTS_LOCAL) &&
 	  (gotname & (F_IPV4 | F_IPV6)) &&
 	  !strchr(daemon->namebuff, '.') &&
 	  strlen(daemon->namebuff) != 0)
-	{
+	flags = check_for_local_domain(daemon->namebuff, now) ? F_NOERR : F_NXDOMAIN;
-	  flags = F_NOERR;
-	  goto reply;
-	}
-      
-      flags = 0;
-
-      /* no available server. */
-      if (!lookup_domain(daemon->namebuff, gotname, &first, &last))
-	{
-	  ede = EDE_NOT_READY;
-	  goto reply;
-	}
       
       /* Configured answer. */
-      if ((flags = is_local_answer(now, first, daemon->namebuff)))
+      if (flags || ede == EDE_NOT_READY)
 	goto reply;
       
       master = daemon->serverarray[first];
@@ -2038,15 +2034,24 @@ unsigned char *tcp_request(int confd, time_t now,
 	      struct server *master;
 	      int start;
 
+	      if (lookup_domain(daemon->namebuff, gotname, &first, &last))
+		flags = is_local_answer(now, first, daemon->namebuff);
+	      else
+		{
+		  /* No configured servers */
+		  ede = EDE_NOT_READY;
+		  flags = 0;
+		}
+	      
 	      /* don't forward A or AAAA queries for simple names, except the empty name */
-	      if (option_bool(OPT_NODOTS_LOCAL) &&
+	      if (!flags &&
+		  option_bool(OPT_NODOTS_LOCAL) &&
 		  (gotname & (F_IPV4 | F_IPV6)) &&
 		  !strchr(daemon->namebuff, '.') &&
 		  strlen(daemon->namebuff) != 0)
-		flags = F_NOERR;
+		flags = check_for_local_domain(daemon->namebuff, now) ? F_NOERR : F_NXDOMAIN;
-	      else if (!lookup_domain(daemon->namebuff, gotname, &first, &last))
+		
-		ede = EDE_NOT_READY;  /* No configured servers */
+	      if (!flags && ede != EDE_NOT_READY)
-	      else if (!(flags = is_local_answer(now, first, daemon->namebuff)))
 		{
 		  master = daemon->serverarray[first];
 		  

src/helper.c

@@ -432,7 +432,8 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 		buf = grab_extradata_lua(buf, end, "relay_address");
 	      else if (data.giaddr.s_addr != 0)
 		{
-		  lua_pushstring(lua, inet_ntoa(data.giaddr));
+		  inet_ntop(AF_INET, &data.giaddr, daemon->addrbuff, ADDRSTRLEN);
+		  lua_pushstring(lua, daemon->addrbuff);
 		  lua_setfield(lua, -2, "relay_address");
 		}
 	      
@@ -611,7 +612,12 @@ int create_helper(int event_fd, int err_fd, uid_t uid, gid_t gid, long max_fd)
 	  if (is6)
 	    buf = grab_extradata(buf, end, "DNSMASQ_RELAY_ADDRESS", &err);
 	  else
-	    my_setenv("DNSMASQ_RELAY_ADDRESS", data.giaddr.s_addr != 0 ? inet_ntoa(data.giaddr) : NULL, &err); 
+	    {
+	      const char *giaddr = NULL;
+	      if (data.giaddr.s_addr != 0)
+		  giaddr = inet_ntop(AF_INET, &data.giaddr, daemon->addrbuff, ADDRSTRLEN);
+	      my_setenv("DNSMASQ_RELAY_ADDRESS", giaddr, &err);
+	    }
 	  
 	  for (i = 0; buf; i++)
 	    {

src/network.c

@@ -1688,7 +1688,7 @@ int reload_servers(char *fname)
       memset(&addr, 0, sizeof(addr));
       memset(&source_addr, 0, sizeof(source_addr));
       
-      if ((addr.in.sin_addr.s_addr = inet_addr(token)) != (in_addr_t) -1)
+      if (inet_pton(AF_INET, token, &addr.in.sin_addr) > 0)
 	{
 #ifdef HAVE_SOCKADDR_SA_LEN
 	  source_addr.in.sin_len = addr.in.sin_len = sizeof(source_addr.in);

src/option.c

@@ -3612,7 +3612,9 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 		for (configs = daemon->dhcp_conf; configs; configs = configs->next) 
 		  if ((configs->flags & CONFIG_ADDR) && configs->addr.s_addr == in.s_addr)
 		    {
-		      sprintf(errstr, _("duplicate dhcp-host IP address %s"),  inet_ntoa(in));
+		      inet_ntop(AF_INET, &in, daemon->addrbuff, ADDRSTRLEN);
+		      sprintf(errstr, _("duplicate dhcp-host IP address %s"),
+			      daemon->addrbuff);
 		      return 0;
 		    }	      
 	      }
@@ -5234,6 +5236,7 @@ void read_opts(int argc, char **argv, char *compile_opts)
   daemon = opt_malloc(sizeof(struct daemon));
   memset(daemon, 0, sizeof(struct daemon));
   daemon->namebuff = buff;
+  daemon->addrbuff = safe_malloc(ADDRSTRLEN);
   
   /* Set defaults - everything else is zero or NULL */
   daemon->cachesize = CACHESIZ;

src/rfc2131.c

@@ -372,9 +372,22 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
   
   if (!context)
     {
+      const char *via;
+      if (subnet_addr.s_addr)
+	{
+	  via = _("with subnet selector");
+	  inet_ntop(AF_INET, &subnet_addr, daemon->addrbuff, ADDRSTRLEN);
+	}
+      else
+	{
+	  via = _("via");
+	  if (mess->giaddr.s_addr)
+	    inet_ntop(AF_INET, &mess->giaddr, daemon->addrbuff, ADDRSTRLEN);
+	  else
+	    safe_strncpy(daemon->addrbuff, iface_name, ADDRSTRLEN);
+	}
       my_syslog(MS_DHCP | LOG_WARNING, _("no address range available for DHCP request %s %s"),
-		subnet_addr.s_addr ? _("with subnet selector") : _("via"),
+		via, daemon->addrbuff);
-		subnet_addr.s_addr ? inet_ntoa(subnet_addr) : (mess->giaddr.s_addr ? inet_ntoa(mess->giaddr) : iface_name));
       return 0;
     }
 
@@ -383,13 +396,19 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
       struct dhcp_context *context_tmp;
       for (context_tmp = context; context_tmp; context_tmp = context_tmp->current)
 	{
-	  strcpy(daemon->namebuff, inet_ntoa(context_tmp->start));
+	  inet_ntop(AF_INET, &context_tmp->start, daemon->namebuff, MAXDNAME);
 	  if (context_tmp->flags & (CONTEXT_STATIC | CONTEXT_PROXY))
+	    {
+	      inet_ntop(AF_INET, &context_tmp->netmask, daemon->addrbuff, ADDRSTRLEN);
 	      my_syslog(MS_DHCP | LOG_INFO, _("%u available DHCP subnet: %s/%s"),
-		      ntohl(mess->xid), daemon->namebuff, inet_ntoa(context_tmp->netmask));
+			ntohl(mess->xid), daemon->namebuff, daemon->addrbuff);
+	    }
 	  else
+	    {
+	      inet_ntop(AF_INET, &context_tmp->end, daemon->addrbuff, ADDRSTRLEN);
 	      my_syslog(MS_DHCP | LOG_INFO, _("%u available DHCP range: %s -- %s"),
-		      ntohl(mess->xid), daemon->namebuff, inet_ntoa(context_tmp->end));
+			ntohl(mess->xid), daemon->namebuff, daemon->addrbuff);
+	    }
 	}
     }
   
@@ -1031,8 +1050,9 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	  config->addr.s_addr == option_addr(opt).s_addr)
 	{
 	  prettyprint_time(daemon->dhcp_buff, DECLINE_BACKOFF);
+	  inet_ntop(AF_INET, &config->addr, daemon->addrbuff, ADDRSTRLEN);
 	  my_syslog(MS_DHCP | LOG_WARNING, _("disabling DHCP static address %s for %s"), 
-		    inet_ntoa(config->addr), daemon->dhcp_buff);
+		    daemon->addrbuff, daemon->dhcp_buff);
 	  config->flags |= CONFIG_DECLINED;
 	  config->decline_time = now;
 	}
@@ -1078,7 +1098,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 	  
 	  if (have_config(config, CONFIG_ADDR))
 	    {
-	      char *addrs = inet_ntoa(config->addr);
+	      inet_ntop(AF_INET, &config->addr, daemon->addrbuff, ADDRSTRLEN);
 	      
 	      if ((ltmp = lease_find_by_addr(config->addr)) && 
 		  ltmp != lease &&
@@ -1088,7 +1108,7 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		  unsigned char *mac = extended_hwaddr(ltmp->hwaddr_type, ltmp->hwaddr_len,
 						       ltmp->hwaddr, ltmp->clid_len, ltmp->clid, &len);
 		  my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it is leased to %s"),
-			    addrs, print_mac(daemon->namebuff, mac, len));
+			    daemon->addrbuff, print_mac(daemon->namebuff, mac, len));
 		}
 	      else
 		{
@@ -1097,10 +1117,10 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		    if (context->router.s_addr == config->addr.s_addr)
 		      break;
 		  if (tmp)
-		    my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it is in use by the server or relay"), addrs);
+		    my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it is in use by the server or relay"), daemon->addrbuff);
 		  else if (have_config(config, CONFIG_DECLINED) &&
 			   difftime(now, config->decline_time) < (float)DECLINE_BACKOFF)
-		    my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it was previously declined"), addrs);
+		    my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it was previously declined"), daemon->addrbuff);
 		  else
 		    conf = config->addr;
 		}
@@ -1303,9 +1323,10 @@ size_t dhcp_reply(struct dhcp_context *context, char *iface_name, int int_index,
 		 a lease from one of it's MACs to give the address to another. */
 	      if (config && config_has_mac(config, ltmp->hwaddr, ltmp->hwaddr_len, ltmp->hwaddr_type))
 		{
+		  inet_ntop(AF_INET, &ltmp->addr, daemon->addrbuff, ADDRSTRLEN);
 		  my_syslog(MS_DHCP | LOG_INFO, _("abandoning lease to %s of %s"),
 			    print_mac(daemon->namebuff, ltmp->hwaddr, ltmp->hwaddr_len), 
-			    inet_ntoa(ltmp->addr));
+			    daemon->addrbuff);
 		  lease = ltmp;
 		}
 	      else
@@ -1674,23 +1695,21 @@ static void add_extradata_opt(struct dhcp_lease *lease, unsigned char *opt)
 static void log_packet(char *type, void *addr, unsigned char *ext_mac, 
 		       int mac_len, char *interface, char *string, char *err, u32 xid)
 {
-  struct in_addr a;
- 
   if (!err && !option_bool(OPT_LOG_OPTS) && option_bool(OPT_QUIET_DHCP))
     return;
   
-  /* addr may be misaligned */
+  daemon->addrbuff[0] = 0;
   if (addr)
-    memcpy(&a, addr, sizeof(a));
+    inet_ntop(AF_INET, addr, daemon->addrbuff, ADDRSTRLEN);
   
   print_mac(daemon->namebuff, ext_mac, mac_len);
   
-  if(option_bool(OPT_LOG_OPTS))
+  if (option_bool(OPT_LOG_OPTS))
     my_syslog(MS_DHCP | LOG_INFO, "%u %s(%s) %s%s%s %s%s",
 	      ntohl(xid), 
 	      type,
 	      interface, 
-	       addr ? inet_ntoa(a) : "",
+	      daemon->addrbuff,
 	      addr ? " " : "",
 	      daemon->namebuff,
 	      string ? string : "",
@@ -1699,7 +1718,7 @@ static void log_packet(char *type, void *addr, unsigned char *ext_mac,
     my_syslog(MS_DHCP | LOG_INFO, "%s(%s) %s%s%s %s%s",
 	      type,
 	      interface, 
-	      addr ? inet_ntoa(a) : "",
+	      daemon->addrbuff,
 	      addr ? " " : "",
 	      daemon->namebuff,
 	      string ? string : "",
@@ -1707,9 +1726,9 @@ static void log_packet(char *type, void *addr, unsigned char *ext_mac,
   
 #ifdef HAVE_UBUS
   if (!strcmp(type, "DHCPACK"))
-		ubus_event_bcast("dhcp.ack", daemon->namebuff, addr ? inet_ntoa(a) : NULL, string ? string : NULL, interface);
+    ubus_event_bcast("dhcp.ack", daemon->namebuff, addr ? daemon->addrbuff : NULL, string, interface);
   else if (!strcmp(type, "DHCPRELEASE"))
-		ubus_event_bcast("dhcp.release", daemon->namebuff, addr ? inet_ntoa(a) : NULL, string ? string : NULL, interface);
+    ubus_event_bcast("dhcp.release", daemon->namebuff, addr ? daemon->addrbuff : NULL, string, interface);
 #endif
 }
 
@@ -1861,7 +1880,10 @@ static size_t dhcp_packet_size(struct dhcp_packet *mess, unsigned char *agent_id
   if (option_bool(OPT_LOG_OPTS))
     {
       if (mess->siaddr.s_addr != 0)
-	my_syslog(MS_DHCP | LOG_INFO, _("%u next server: %s"), ntohl(mess->xid), inet_ntoa(mess->siaddr));
+	{
+	  inet_ntop(AF_INET, &mess->siaddr, daemon->addrbuff, ADDRSTRLEN);
+	  my_syslog(MS_DHCP | LOG_INFO, _("%u next server: %s"), ntohl(mess->xid), daemon->addrbuff);
+	}
       
       if ((mess->flags & htons(0x8000)) && mess->ciaddr.s_addr == 0)
 	my_syslog(MS_DHCP | LOG_INFO, _("%u broadcast response"), ntohl(mess->xid));

src/ubus.c

@@ -21,7 +21,6 @@
 #include <libubus.h>
 
 static struct blob_buf b;
-static int notify;
 static int error_logged = 0;
 
 static int ubus_handle_metrics(struct ubus_context *ctx, struct ubus_object *obj,
@@ -78,17 +77,16 @@ static void ubus_subscribe_cb(struct ubus_context *ctx, struct ubus_object *obj)
   (void)ctx;
 
   my_syslog(LOG_DEBUG, _("UBus subscription callback: %s subscriber(s)"), obj->has_subscribers ? "1" : "0");
-  notify = obj->has_subscribers;
 }
 
 static void ubus_destroy(struct ubus_context *ubus)
 {
+  ubus_free(ubus);
+  daemon->ubus = NULL;
+  
   // Forces re-initialization when we're reusing the same definitions later on.
   ubus_object.id = 0;
   ubus_object_type.id = 0;
-
-  ubus_free(ubus);
-  daemon->ubus = NULL;
 }
 
 static void ubus_disconnect_cb(struct ubus_context *ubus)
@@ -312,7 +310,7 @@ void ubus_event_bcast(const char *type, const char *mac, const char *ip, const c
   struct ubus_context *ubus = (struct ubus_context *)daemon->ubus;
   int ret;
 
-  if (!ubus || !notify)
+  if (!ubus || !ubus_object.has_subscribers)
     return;
 
   blob_buf_init(&b, BLOBMSG_TYPE_TABLE);
@@ -336,7 +334,7 @@ void ubus_event_bcast_connmark_allowlist_refused(u32 mark, const char *name)
   struct ubus_context *ubus = (struct ubus_context *)daemon->ubus;
   int ret;
 
-  if (!ubus || !notify)
+  if (!ubus || !ubus_object.has_subscribers)
     return;
 
   blob_buf_init(&b, 0);
@@ -353,7 +351,7 @@ void ubus_event_bcast_connmark_allowlist_resolved(u32 mark, const char *name, co
   struct ubus_context *ubus = (struct ubus_context *)daemon->ubus;
   int ret;
 
-  if (!ubus || !notify)
+  if (!ubus || !ubus_object.has_subscribers)
     return;
 
   blob_buf_init(&b, 0);