Re: relayd: check proc_compose return values

On Sat, 25 Jul 2026 21:05:33 +0200,
Rafael Sadowski <[email protected]> wrote:
> 
> OK?
>

reads OK kirill@

> commit d7c2b3a44c48d2759fa510be891cefd49dece2ea
> Author: Rafael Sadowski <[email protected]>
> Date:   Sat Jul 25 20:46:57 2026 +0200
> 
>     relayd: check proc_compose return values
>     
>     Fatal on config, setup, and startup imsg send failures. Inconsistent
>     state means we can't recover.
>     
>     Warn on per-request responses and sync messages. A single dropped
>     message shouldn't kill the whole process.
> 
> diff --git a/agentx_control.c b/agentx_control.c
> index 7af1c0e..a6f5ef4 100644
> --- a/agentx_control.c
> +++ b/agentx_control.c
> @@ -427,9 +427,11 @@ agentx_init(struct relayd *nenv)
>  void
>  agentx_nofd(struct agentx *usa, void *cookie, int close)
>  {
> -	if (!close)
> -		proc_compose(env->sc_ps, PROC_PARENT, IMSG_AGENTXSOCK, NULL, 0);
> -	else {
> +	if (!close) {
> +		if (proc_compose(env->sc_ps, PROC_PARENT, IMSG_AGENTXSOCK,
> +		    NULL, 0) == -1)
> +			log_warn("%s: proc_compose", __func__);
> +	} else {
>  		sa = NULL;
>  		agentx_init(env);
>  		event_del(&(env->sc_agentxev));
> @@ -456,7 +458,9 @@ agentx_setsock(struct relayd *lenv, enum privsep_procid id)
>  		s = -1;
>  	}
>   done:
> -	proc_compose_imsg(lenv->sc_ps, id, -1, IMSG_AGENTXSOCK, -1, s, NULL, 0);
> +	if (proc_compose_imsg(lenv->sc_ps, id, -1, IMSG_AGENTXSOCK, -1, s,
> +	    NULL, 0) == -1)
> +		log_warn("%s: proc_compose_imsg", __func__);
>  }
>  
>  void
> @@ -485,7 +489,9 @@ void
>  agentx_sock(int fd, short event, void *arg)
>  {
>  	if (event & EV_TIMEOUT) {
> -		proc_compose(env->sc_ps, PROC_PARENT, IMSG_AGENTXSOCK, NULL, 0);
> +		if (proc_compose(env->sc_ps, PROC_PARENT, IMSG_AGENTXSOCK,
> +		    NULL, 0) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  		return;
>  	}
>  	if (event & EV_WRITE) {
> diff --git a/config.c b/config.c
> index b273fd7..b4ec0aa 100644
> --- a/config.c
> +++ b/config.c
> @@ -230,7 +230,9 @@ config_setreset(struct relayd *env, u_int reset)
>  		if ((reset & ps->ps_what[id]) == 0 ||
>  		    id == privsep_process)
>  			continue;
> -		proc_compose(ps, id, IMSG_CTL_RESET, &reset, sizeof(reset));
> +		if (proc_compose(ps, id, IMSG_CTL_RESET, &reset,
> +		    sizeof(reset)) == -1)
> +			fatal("%s: proc_compose", __func__);
>  
>  		/*
>  		 * XXX Make sure that the reset message is sent
> @@ -294,7 +296,9 @@ config_getcfg(struct relayd *env, struct imsg *imsg)
>  	}
>  
>  	if (privsep_process != PROC_PARENT)
> -		proc_compose(env->sc_ps, PROC_PARENT, IMSG_CFG_DONE, NULL, 0);
> +		if (proc_compose(env->sc_ps, PROC_PARENT, IMSG_CFG_DONE, NULL,
> +		    0) == -1)
> +			fatal("%s: proc_compose", __func__);
>  
>  	return (0);
>  }
> @@ -327,11 +331,13 @@ config_settable(struct relayd *env, struct table *tb)
>  			iov[c++].iov_len = strlen(tb->sendbuf);
>  		}
>  
> -		proc_composev(ps, id, IMSG_CFG_TABLE, iov, c);
> +		if (proc_composev(ps, id, IMSG_CFG_TABLE, iov, c) == -1)
> +			fatal("%s: proc_composev", __func__);
>  
>  		TAILQ_FOREACH(host, &tb->hosts, entry) {
> -			proc_compose(ps, id, IMSG_CFG_HOST,
> -			    &host->conf, sizeof(host->conf));
> +			if (proc_compose(ps, id, IMSG_CFG_HOST, &host->conf,
> +			    sizeof(host->conf)) == -1)
> +				fatal("%s: proc_compose", __func__);
>  		}
>  	}
>  
> @@ -445,13 +451,15 @@ config_setrdr(struct relayd *env, struct rdr *rdr)
>  		DPRINTF("%s: sending rdr %s to %s", __func__,
>  		    rdr->conf.name, ps->ps_title[id]);
>  
> -		proc_compose(ps, id, IMSG_CFG_RDR,
> -		    &rdr->conf, sizeof(rdr->conf));
> +		if (proc_compose(ps, id, IMSG_CFG_RDR, &rdr->conf,
> +		    sizeof(rdr->conf)) == -1)
> +			fatal("%s: proc_compose", __func__);
>  
>  		TAILQ_FOREACH(virt, &rdr->virts, entry) {
>  			virt->rdrid = rdr->conf.id;
> -			proc_compose(ps, id, IMSG_CFG_VIRT,
> -			    virt, sizeof(*virt));
> +			if (proc_compose(ps, id, IMSG_CFG_VIRT, virt,
> +			    sizeof(*virt)) == -1)
> +				fatal("%s: proc_compose", __func__);
>  		}
>  	}
>  
> @@ -539,12 +547,14 @@ config_setrt(struct relayd *env, struct router *rt)
>  		DPRINTF("%s: sending router %s to %s tbl %d", __func__,
>  		    rt->rt_conf.name, ps->ps_title[id], rt->rt_conf.gwtable);
>  
> -		proc_compose(ps, id, IMSG_CFG_ROUTER,
> -		    &rt->rt_conf, sizeof(rt->rt_conf));
> +		if (proc_compose(ps, id, IMSG_CFG_ROUTER,
> +		    &rt->rt_conf, sizeof(rt->rt_conf)) == -1)
> +			fatal("%s: proc_compose", __func__);
>  
>  		TAILQ_FOREACH(nr, &rt->rt_netroutes, nr_entry) {
> -			proc_compose(ps, id, IMSG_CFG_ROUTE,
> -			    &nr->nr_conf, sizeof(nr->nr_conf));
> +			if (proc_compose(ps, id, IMSG_CFG_ROUTE,
> +			    &nr->nr_conf, sizeof(nr->nr_conf)) == -1)
> +				fatal("%s: proc_compose", __func__);
>  		}
>  	}
>  
> @@ -650,7 +660,8 @@ config_setproto(struct relayd *env, struct protocol *proto)
>  			iov[c++].iov_len = strlen(proto->style) + 1;
>  		}
>  
> -		proc_composev(ps, id, IMSG_CFG_PROTO, iov, c);
> +		if (proc_composev(ps, id, IMSG_CFG_PROTO, iov, c) == -1)
> +			fatal("%s: proc_composev", __func__);
>  	}
>  
>  	return (0);
> @@ -701,7 +712,8 @@ config_setrule(struct relayd *env, struct protocol *proto)
>  					rule->rule_ctl.kvlen[i].value = -1;
>  			}
>  
> -			proc_composev(ps, id, IMSG_CFG_RULE, iov, c);
> +			if (proc_composev(ps, id, IMSG_CFG_RULE, iov, c) == -1)
> +				fatal("%s: proc_composev", __func__);
>  		}
>  	}
>  
> @@ -1012,7 +1024,9 @@ config_setrelay(struct relayd *env, struct relay *rlay)
>  			iov[c].iov_base = &crt;
>  			iov[c++].iov_len = sizeof(crt);
>  
> -			proc_composev(ps, id, IMSG_CFG_RELAY_TABLE, iov, c);
> +			if (proc_composev(ps, id, IMSG_CFG_RELAY_TABLE, iov,
> +			    c) == -1)
> +				fatal("%s: proc_composev", __func__);
>  		}
>  	}
>  
> diff --git a/control.c b/control.c
> index 1d4a3e6..3757bd0 100644
> --- a/control.c
> +++ b/control.c
> @@ -362,8 +362,9 @@ control_dispatch_imsg(int fd, short event, void *arg)
>  			proc_forward_imsg(env->sc_ps, &imsg, PROC_PARENT);
>  			break;
>  		case IMSG_CTL_POLL:
> -			proc_compose(env->sc_ps, PROC_HCE,
> -			    IMSG_CTL_POLL, NULL, 0);
> +			if (proc_compose(env->sc_ps, PROC_HCE, IMSG_CTL_POLL,
> +			    NULL, 0) == -1)
> +				log_warn("%s: proc_compose", __func__);
>  			imsg_compose_event(&c->iev, IMSG_CTL_OK,
>  			    0, ps->ps_instance + 1, -1, NULL, 0);
>  			break;
> diff --git a/hce.c b/hce.c
> index 05c1555..af4e7b0 100644
> --- a/hce.c
> +++ b/hce.c
> @@ -136,7 +136,8 @@ hce_launch_checks(int fd, short event, void *arg)
>  	/*
>  	 * notify pfe checks are done and schedule next check
>  	 */
> -	proc_compose(env->sc_ps, PROC_PFE, IMSG_SYNC, NULL, 0);
> +	if (proc_compose(env->sc_ps, PROC_PFE, IMSG_SYNC, NULL, 0) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  	TAILQ_FOREACH(table, env->sc_tables, entry) {
>  		TAILQ_FOREACH(host, &table->hosts, entry) {
>  			if ((host->flags & F_CHECK_DONE) == 0)
> @@ -246,7 +247,9 @@ hce_notify_done(struct host *host, enum host_error he)
>  	if (msg)
>  		log_debug("%s: %s (%s)", __func__, host->conf.name, msg);
>  
> -	proc_compose(env->sc_ps, PROC_PFE, IMSG_HOST_STATUS, &st, sizeof(st));
> +	if (proc_compose(env->sc_ps, PROC_PFE, IMSG_HOST_STATUS, &st,
> +	    sizeof(st)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  	if (host->up != host->last_up)
>  		logopt = RELAYD_OPT_LOGUPDATE;
>  
> diff --git a/pfe.c b/pfe.c
> index c66ad06..d527e3c 100644
> --- a/pfe.c
> +++ b/pfe.c
> @@ -151,8 +151,9 @@ pfe_dispatch_hce(int fd, struct privsep_proc *p, struct imsg *imsg)
>  			break;
>  
>  		/* Forward to relay engine(s) */
> -		proc_compose(env->sc_ps, PROC_RELAY,
> -		    IMSG_HOST_STATUS, &st, sizeof(st));
> +		if (proc_compose(env->sc_ps, PROC_RELAY, IMSG_HOST_STATUS, &st,
> +		    sizeof(st)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  
>  		if ((table = table_find(env, host->conf.tableid)) ==
>  		    NULL)
> @@ -279,8 +280,9 @@ pfe_dispatch_relay(int fd, struct privsep_proc *p, struct imsg *imsg)
>  			fatalx("%s: invalid relay proc", __func__);
>  		if (natlook(env, &cnl) != 0)
>  			cnl.in = -1;
> -		proc_compose_imsg(env->sc_ps, PROC_RELAY, cnl.proc,
> -		    IMSG_NATLOOK, -1, -1, &cnl, sizeof(cnl));
> +		if (proc_compose_imsg(env->sc_ps, PROC_RELAY, cnl.proc,
> +		    IMSG_NATLOOK, -1, -1, &cnl, sizeof(cnl)) == -1)
> +			log_warn("%s: proc_compose_imsg", __func__);
>  		break;
>  	case IMSG_STATISTICS:
>  		if (imsg_get_data(imsg, &crs, sizeof(crs)) == -1)
> @@ -455,8 +457,9 @@ show_sessions(struct ctl_conn *c)
>  		/*
>  		 * Request all the running sessions from the process
>  		 */
> -		proc_compose_imsg(env->sc_ps, PROC_RELAY, proc,
> -		    IMSG_CTL_SESSION, -1, -1, &cid, sizeof(cid));
> +		if (proc_compose_imsg(env->sc_ps, PROC_RELAY, proc,
> +		    IMSG_CTL_SESSION, -1, -1, &cid, sizeof(cid)) == -1)
> +			log_warn("%s: proc_compose_imsg", __func__);
>  		c->waiting++;
>  	}
>  }
> @@ -544,12 +547,14 @@ disable_table(struct ctl_conn *c, struct ctl_id *id)
>  	table->up = 0;
>  	TAILQ_FOREACH(host, &table->hosts, entry)
>  		host->up = HOST_UNKNOWN;
> -	proc_compose(env->sc_ps, PROC_HCE, IMSG_TABLE_DISABLE,
> -	    &table->conf.id, sizeof(table->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_HCE, IMSG_TABLE_DISABLE,
> +	    &table->conf.id, sizeof(table->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	/* Forward to relay engine(s) */
> -	proc_compose(env->sc_ps, PROC_RELAY, IMSG_TABLE_DISABLE,
> -	    &table->conf.id, sizeof(table->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_RELAY, IMSG_TABLE_DISABLE,
> +	    &table->conf.id, sizeof(table->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	log_debug("%s: table %d", __func__, table->conf.id);
>  	pfe_sync();
> @@ -580,12 +585,14 @@ enable_table(struct ctl_conn *c, struct ctl_id *id)
>  	table->up = 0;
>  	TAILQ_FOREACH(host, &table->hosts, entry)
>  		host->up = HOST_UNKNOWN;
> -	proc_compose(env->sc_ps, PROC_HCE, IMSG_TABLE_ENABLE,
> -	    &table->conf.id, sizeof(table->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_HCE, IMSG_TABLE_ENABLE,
> +	    &table->conf.id, sizeof(table->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	/* Forward to relay engine(s) */
> -	proc_compose(env->sc_ps, PROC_RELAY, IMSG_TABLE_ENABLE,
> -	    &table->conf.id, sizeof(table->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_RELAY, IMSG_TABLE_ENABLE,
> +	    &table->conf.id, sizeof(table->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	log_debug("%s: table %d", __func__, table->conf.id);
>  	pfe_sync();
> @@ -627,12 +634,15 @@ disable_host(struct ctl_conn *c, struct ctl_id *id, struct host *host)
>  	host->check_cnt = 0;
>  	host->up_cnt = 0;
>  
> -	proc_compose(env->sc_ps, PROC_HCE, IMSG_HOST_DISABLE,
> -	    &host->conf.id, sizeof(host->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_HCE, IMSG_HOST_DISABLE,
> +	    &host->conf.id, sizeof(host->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	/* Forward to relay engine(s) */
> -	proc_compose(env->sc_ps, PROC_RELAY, IMSG_HOST_DISABLE,
> -	    &host->conf.id, sizeof(host->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_RELAY, IMSG_HOST_DISABLE,
> +	    &host->conf.id, sizeof(host->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
> +
>  	log_debug("%s: host %d", __func__, host->conf.id);
>  
>  	if (!host->conf.parentid) {
> @@ -680,12 +690,14 @@ enable_host(struct ctl_conn *c, struct ctl_id *id, struct host *host)
>  	host->flags &= ~(F_DEL);
>  	host->flags &= ~(F_ADD);
>  
> -	proc_compose(env->sc_ps, PROC_HCE, IMSG_HOST_ENABLE,
> -	    &host->conf.id, sizeof(host->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_HCE, IMSG_HOST_ENABLE,
> +	    &host->conf.id, sizeof(host->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	/* Forward to relay engine(s) */
> -	proc_compose(env->sc_ps, PROC_RELAY, IMSG_HOST_ENABLE,
> -	    &host->conf.id, sizeof(host->conf.id));
> +	if (proc_compose(env->sc_ps, PROC_RELAY, IMSG_HOST_ENABLE,
> +	    &host->conf.id, sizeof(host->conf.id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	log_debug("%s: host %d", __func__, host->conf.id);
>  
> @@ -808,8 +820,9 @@ pfe_sync(void)
>  		    demote.level, table->conf.name, table->conf.demote_group);
>  		(void)strlcpy(demote.group, table->conf.demote_group,
>  		    sizeof(demote.group));
> -		proc_compose(env->sc_ps, PROC_PARENT, IMSG_DEMOTE,
> -		    &demote, sizeof(demote));
> +		if (proc_compose(env->sc_ps, PROC_PARENT, IMSG_DEMOTE,
> +		    &demote, sizeof(demote)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  	}
>  }
>  
> diff --git a/pfe_route.c b/pfe_route.c
> index 5e0044c..aad82e4 100644
> --- a/pfe_route.c
> +++ b/pfe_route.c
> @@ -82,8 +82,10 @@ sync_routes(struct relayd *env, struct router *rt)
>  			memcpy(&crt.host, &host->conf, sizeof(host->conf));
>  			memcpy(&crt.rt, &rt->rt_conf, sizeof(rt->rt_conf));
>  
> -			proc_compose(env->sc_ps, PROC_PARENT,
> -			    IMSG_RTMSG, &crt, sizeof(crt));
> +			if (proc_compose(env->sc_ps, PROC_PARENT, IMSG_RTMSG,
> +			    &crt, sizeof(crt)) == -1) {
> +				log_warn("%s: proc_compose", __func__);
> +			}
>  		}
>  	}
>  }
> diff --git a/relay.c b/relay.c
> index 58e57b7..8469f8d 100644
> --- a/relay.c
> +++ b/relay.c
> @@ -359,14 +359,17 @@ relay_init(struct privsep *ps, struct privsep_proc *p, void *arg)
>  void
>  relay_session_publish(struct rsession *s)
>  {
> -	proc_compose(env->sc_ps, PROC_PFE, IMSG_SESS_PUBLISH, s, sizeof(*s));
> +	if (proc_compose(env->sc_ps, PROC_PFE, IMSG_SESS_PUBLISH, s,
> +	    sizeof(*s)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  }
>  
>  void
>  relay_session_unpublish(struct rsession *s)
>  {
> -	proc_compose(env->sc_ps, PROC_PFE, IMSG_SESS_UNPUBLISH,
> -	    &s->se_id, sizeof(s->se_id));
> +	if (proc_compose(env->sc_ps, PROC_PFE, IMSG_SESS_UNPUBLISH,
> +	    &s->se_id, sizeof(s->se_id)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  }
>  
>  void
> @@ -417,8 +420,9 @@ relay_statistics(int fd, short events, void *arg)
>  
>  		crs.id = rlay->rl_conf.id;
>  		crs.proc = ps->ps_instance;
> -		proc_compose(env->sc_ps, PROC_PFE, IMSG_STATISTICS,
> -		    &crs, sizeof(crs));
> +		if (proc_compose(env->sc_ps, PROC_PFE, IMSG_STATISTICS, &crs,
> +		    sizeof(crs)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  
>  		for (con = SPLAY_ROOT(&rlay->rl_sessions);
>  		    con != NULL; con = next_con) {
> @@ -1233,8 +1237,9 @@ relay_accept(int fd, short event, void *arg)
>  		memcpy(&cnl->src, &con->se_in.ss, sizeof(cnl->src));
>  		memcpy(&cnl->dst, &con->se_sockname, sizeof(cnl->dst));
>  
> -		proc_compose(env->sc_ps, PROC_PFE, IMSG_NATLOOK,
> -		    cnl, sizeof(*cnl));
> +		if (proc_compose(env->sc_ps, PROC_PFE, IMSG_NATLOOK,
> +		    cnl, sizeof(*cnl)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  
>  		/* Schedule timeout */
>  		evtimer_set(&con->se_ev, relay_natlook, con);
> @@ -1492,8 +1497,9 @@ relay_bindanyreq(struct rsession *con, in_port_t port, int proto)
>  	bnd.bnd_port = port;
>  	bnd.bnd_proto = proto;
>  	bcopy(&con->se_in.ss, &bnd.bnd_ss, sizeof(bnd.bnd_ss));
> -	proc_compose(env->sc_ps, PROC_PARENT, IMSG_BINDANY,
> -	    &bnd, sizeof(bnd));
> +	if (proc_compose(env->sc_ps, PROC_PARENT, IMSG_BINDANY,
> +	    &bnd, sizeof(bnd)) == -1)
> +		log_warn("%s: proc_compose", __func__);
>  
>  	/* Schedule timeout */
>  	evtimer_set(&con->se_ev, relay_bindany, con);
> @@ -1815,8 +1821,9 @@ relay_close(struct rsession *con, const char *msg, int err)
>  
>  	if (con->se_cnl != NULL) {
>  #if 0
> -		proc_compose_imsg(env->sc_ps, PROC_PFE, -1, IMSG_KILLSTATES, -1,
> -		    cnl, sizeof(*cnl));
> +		if (proc_compose_imsg(env->sc_ps, PROC_PFE, -1,
> +		    IMSG_KILLSTATES, -1, cnl, sizeof(*cnl)) == -1)
> +			log_warn("%s: proc_compose_imsg", __func__);
>  #endif
>  		free(con->se_cnl);
>  	}
> @@ -1965,12 +1972,14 @@ relay_dispatch_pfe(int fd, struct privsep_proc *p, struct imsg *imsg)
>  			    &rlay->rl_sessions) {
>  				memcpy(&se, con, sizeof(se));
>  				se.se_cid = cid;
> -				proc_compose(env->sc_ps, p->p_id,
> -				    IMSG_CTL_SESSION, &se, sizeof(se));
> +				if (proc_compose(env->sc_ps, p->p_id,
> +				    IMSG_CTL_SESSION, &se, sizeof(se)) == -1)
> +					log_warn("%s: proc_compose", __func__);
>  			}
>  		}
> -		proc_compose(env->sc_ps, p->p_id, IMSG_CTL_END,
> -		    &cid, sizeof(cid));
> +		if (proc_compose(env->sc_ps, p->p_id, IMSG_CTL_END,
> +		    &cid, sizeof(cid)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  		break;
>  	default:
>  		return (-1);
> diff --git a/relay_udp.c b/relay_udp.c
> index 7226861..7403fac 100644
> --- a/relay_udp.c
> +++ b/relay_udp.c
> @@ -316,8 +316,9 @@ relay_udp_server(int fd, short sig, void *arg)
>  		cnl->proto = IPPROTO_UDP;
>  		bcopy(&con->se_in.ss, &cnl->src, sizeof(cnl->src));
>  		bcopy(&rlay->rl_conf.ss, &cnl->dst, sizeof(cnl->dst));
> -		proc_compose(env->sc_ps, PROC_PFE,
> -		    IMSG_NATLOOK, cnl, sizeof(*cnl));
> +		if (proc_compose(env->sc_ps, PROC_PFE, IMSG_NATLOOK, cnl,
> +		    sizeof(*cnl)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  
>  		/* Schedule timeout */
>  		evtimer_set(&con->se_ev, relay_natlook, con);
> diff --git a/relayd.c b/relayd.c
> index b174fc8..5de0cc1 100644
> --- a/relayd.c
> +++ b/relayd.c
> @@ -314,8 +314,9 @@ parent_configure(struct relayd *env)
>  	for (id = 0; id < PROC_MAX; id++) {
>  		if (id == privsep_process)
>  			continue;
> -		proc_compose_imsg(env->sc_ps, id, -1, IMSG_CFG_DONE, -1,
> -		    -1, &env->sc_conf, sizeof(env->sc_conf));
> +		if (proc_compose_imsg(env->sc_ps, id, -1, IMSG_CFG_DONE, -1,
> +		    -1, &env->sc_conf, sizeof(env->sc_conf)) == -1)
> +			fatal("%s: proc_compose_imsg", __func__);
>  	}
>  
>  	ret = 0;
> @@ -373,7 +374,9 @@ parent_configure_done(struct relayd *env)
>  			if (id == privsep_process)
>  				continue;
>  
> -			proc_compose(env->sc_ps, id, IMSG_CTL_START, NULL, 0);
> +			if (proc_compose(env->sc_ps, id, IMSG_CTL_START, NULL,
> +			    0) == -1)
> +				fatal("%s: proc_compose", __func__);
>  		}
>  	}
>  }
> @@ -478,7 +481,9 @@ parent_dispatch_hce(int fd, struct privsep_proc *p, struct imsg *imsg)
>  		scr.name[sizeof(scr.name) - 1] = '\0';
>  		scr.path[sizeof(scr.path) - 1] = '\0';
>  		scr.retval = script_exec(env, &scr);
> -		proc_compose(ps, PROC_HCE, IMSG_SCRIPT, &scr, sizeof(scr));
> +		if (proc_compose(ps, PROC_HCE, IMSG_SCRIPT, &scr,
> +		    sizeof(scr)) == -1)
> +			log_warn("%s: proc_compose", __func__);
>  		break;
>  	case IMSG_CFG_DONE:
>  		parent_configure_done(env);
> @@ -518,8 +523,9 @@ parent_dispatch_relay(int fd, struct privsep_proc *p, struct imsg *imsg)
>  			/* NOTREACHED */
>  		}
>  		s = bindany(&bnd);
> -		proc_compose_imsg(ps, PROC_RELAY, bnd.bnd_proc,
> -		    IMSG_BINDANY, -1, s, &bnd.bnd_id, sizeof(bnd.bnd_id));
> +		if (proc_compose_imsg(ps, PROC_RELAY, bnd.bnd_proc,
> +		    IMSG_BINDANY, -1, s, &bnd.bnd_id, sizeof(bnd.bnd_id)) == -1)
> +			log_warn("%s: proc_compose_imsg", __func__);
>  		break;
>  	case IMSG_CFG_DONE:
>  		parent_configure_done(env);
> @@ -1931,8 +1937,9 @@ parent_tls_ticket_rekey(int fd, short events, void *arg)
>  	key.tt_keyrev = arc4random();
>  	arc4random_buf(key.tt_key, sizeof(key.tt_key));
>  
> -	proc_compose_imsg(env->sc_ps, PROC_RELAY, -1, IMSG_TLSTICKET_REKEY,
> -	    -1, -1, &key, sizeof(key));
> +	if (proc_compose_imsg(env->sc_ps, PROC_RELAY, -1, IMSG_TLSTICKET_REKEY,
> +	    -1, -1, &key, sizeof(key)) == -1)
> +		log_warn("%s: proc_compose_imsg", __func__);
>  
>  	evtimer_set(&rekeyev, parent_tls_ticket_rekey, env);
>  	timerclear(&tv);
> 

-- 
wbr, Kirill