From: Vsevolod Stakhov <vsevolod@rambler-co.ru>
Date: Thu, 24 Jun 2010 14:25:16 +0000 (+0400)
Subject: * Check return value of each rspamd_dispatcher_write as in case of write errors sessi... 
X-Git-Tag: 0.3.1~84
X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=9727678e705943da9e44130ce485b1bdab0a8e96;p=rspamd.git

* Check return value of each rspamd_dispatcher_write as in case of write errors sessions can be destroyed early
---

diff --git a/src/buffer.h b/src/buffer.h
index cbb6c190a..c63fb8c6a 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -93,7 +93,7 @@ void rspamd_set_dispatcher_policy (rspamd_io_dispatcher_t *d,
  */
 gboolean rspamd_dispatcher_write (rspamd_io_dispatcher_t *d,
 												  void *data,
-												  size_t len, gboolean delayed, gboolean allocated);
+												  size_t len, gboolean delayed, gboolean allocated) G_GNUC_WARN_UNUSED_RESULT;
 
 /**
  * Send specified descriptor to dispatcher
@@ -101,7 +101,7 @@ gboolean rspamd_dispatcher_write (rspamd_io_dispatcher_t *d,
  * @param fd descriptor of file
  * @param len length of data
  */
-gboolean rspamd_dispatcher_sendfile (rspamd_io_dispatcher_t *d, int fd, size_t len);
+gboolean rspamd_dispatcher_sendfile (rspamd_io_dispatcher_t *d, int fd, size_t len) G_GNUC_WARN_UNUSED_RESULT;
 
 /**
  * Pause IO events on dispatcher
diff --git a/src/controller.c b/src/controller.c
index 8239d5bad..2644a6d08 100644
--- a/src/controller.c
+++ b/src/controller.c
@@ -161,7 +161,9 @@ check_auth (struct controller_command *cmd, struct controller_session *session)
 
 	if (cmd->privilleged && !session->authorized) {
 		r = snprintf (out_buf, sizeof (out_buf), "not authorized" CRLF);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+			return 0;
+		}
 		return 0;
 	}
 
@@ -178,7 +180,9 @@ counter_write_callback (gpointer key, gpointer value, void *data)
 	int                             r;
 
 	r = snprintf (out_buf, sizeof (out_buf), "%s: %llu" CRLF, name, (unsigned long long int)cd->value);
-	rspamd_dispatcher_write (session->dispatcher, out_buf, r, TRUE, FALSE);
+	if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, TRUE, FALSE)) {
+		msg_warn ("cannot write to socket");
+	}
 }
 
 static gboolean
@@ -223,7 +227,9 @@ write_whole_statfile (struct controller_session *session, char *symbol, struct c
 	}
 
 	i = rspamd_snprintf (out_buf, sizeof (out_buf), "%uL %uL %uL" CRLF, rev, ti, pos);
-	rspamd_dispatcher_write (session->dispatcher, out_buf, i, TRUE, FALSE);
+	if (! rspamd_dispatcher_write (session->dispatcher, out_buf, i, TRUE, FALSE)) {
+		return FALSE;
+	}
 
 	if (!rspamd_dispatcher_write (session->dispatcher, out, pos, TRUE, TRUE)) {
 		return FALSE;
@@ -299,7 +305,12 @@ process_sync_command (struct controller_session *session, char **args)
 	
 	while (binlog_sync (binlog, rev, &time, &data)) {
 		r = snprintf (out_buf, sizeof (out_buf), "%lu %lu %lu" CRLF, (long unsigned)rev, (long unsigned)time, (long unsigned)data->len);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, TRUE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, TRUE, FALSE)) {
+			if (data != NULL) {
+				g_free (data);
+			}
+			return FALSE;
+		}
 		if (!rspamd_dispatcher_write (session->dispatcher, data->data, data->len, TRUE, FALSE)) {
 			if (data != NULL) {
 				g_free (data);
@@ -388,7 +399,7 @@ process_stat_command (struct controller_session *session)
 	return rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
 }
 
-static void
+static gboolean
 process_command (struct controller_command *cmd, char **cmd_args, struct controller_session *session)
 {
 	char                            out_buf[BUFSIZ], *arg, *err_str;
@@ -404,23 +415,31 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 		if (!arg || *arg == '\0') {
 			msg_debug ("empty password passed");
 			r = snprintf (out_buf, sizeof (out_buf), "password command requires one argument" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 		}
 		if (password == NULL) {
 			r = snprintf (out_buf, sizeof (out_buf), "password command disabled in config, authorized access unallowed" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 		}
 		if (strncmp (arg, password, strlen (arg)) == 0) {
 			session->authorized = 1;
 			r = snprintf (out_buf, sizeof (out_buf), "password accepted" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 		}
 		else {
 			session->authorized = 0;
 			r = snprintf (out_buf, sizeof (out_buf), "password NOT accepted" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 		}
 		break;
 	case COMMAND_QUIT:
@@ -429,19 +448,23 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 	case COMMAND_RELOAD:
 		if (check_auth (cmd, session)) {
 			r = snprintf (out_buf, sizeof (out_buf), "reload request sent" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 			kill (getppid (), SIGHUP);
 		}
 		break;
 	case COMMAND_STAT:
 		if (check_auth (cmd, session)) {
-			(void)process_stat_command (session);
+			return process_stat_command (session);
 		}
 		break;
 	case COMMAND_SHUTDOWN:
 		if (check_auth (cmd, session)) {
 			r = snprintf (out_buf, sizeof (out_buf), "shutdown request sent" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 			kill (getppid (), SIGTERM);
 		}
 		break;
@@ -466,7 +489,9 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 				uptime -= hours * 3600 + minutes * 60;
 				r = snprintf (out_buf, sizeof (out_buf), "%d hour%s %d minute%s %d second%s" CRLF, hours, hours > 1 ? "s" : " ", minutes, minutes > 1 ? "s" : " ", (int)uptime, uptime > 1 ? "s" : " ");
 			}
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 		}
 		break;
 	case COMMAND_LEARN:
@@ -475,30 +500,38 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 			if (!arg || *arg == '\0') {
 				msg_debug ("no statfile specified in learn command");
 				r = snprintf (out_buf, sizeof (out_buf), "learn command requires at least two arguments: stat filename and its size" CRLF);
-				rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-				return;
+				if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+					return FALSE;
+				}
+				return TRUE;
 			}
 			arg = *(cmd_args + 1);
 			if (arg == NULL || *arg == '\0') {
 				msg_debug ("no statfile size specified in learn command");
 				r = snprintf (out_buf, sizeof (out_buf), "learn command requires at least two arguments: stat filename and its size" CRLF);
-				rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-				return;
+				if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+					return FALSE;
+				}
+				return TRUE;
 			}
 			size = strtoul (arg, &err_str, 10);
 			if (err_str && *err_str != '\0') {
 				msg_debug ("message size is invalid: %s", arg);
 				r = snprintf (out_buf, sizeof (out_buf), "learn size is invalid" CRLF);
-				rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-				return;
+				if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+					return FALSE;
+				}
+				return TRUE;
 			}
 
 			session->learn_symbol = memory_pool_strdup (session->session_pool, *cmd_args);
 			cl = g_hash_table_lookup (session->cfg->classifiers_symbols, *cmd_args);
 			if (cl == NULL) {
 				r = snprintf (out_buf, sizeof (out_buf), "statfile %s is not defined" CRLF, *cmd_args);
-				rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-				return;
+				if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+					return FALSE;
+				}
+				return TRUE;
 
 			}
 			session->learn_classifier = cl;
@@ -515,8 +548,9 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 						arg = *(cmd_args + 1);
 						if (!arg || *arg == '\0') {
 							r = snprintf (out_buf, sizeof (out_buf), "recipient is not defined" CRLF);
-							rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-							return;
+							if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+								return FALSE;
+							}
 						}
 						session->learn_rcpt = memory_pool_strdup (session->session_pool, arg);
 						break;
@@ -524,8 +558,9 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 						arg = *(cmd_args + 1);
 						if (!arg || *arg == '\0') {
 							r = snprintf (out_buf, sizeof (out_buf), "from is not defined" CRLF);
-							rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-							return;
+							if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+								return FALSE;
+							}
 						}
 						session->learn_from = memory_pool_strdup (session->session_pool, arg);
 						break;
@@ -536,15 +571,18 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 						arg = *(cmd_args + 1);
 						if (!arg || *arg == '\0') {
 							r = snprintf (out_buf, sizeof (out_buf), "multiplier is not defined" CRLF);
-							rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-							return;
+							if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+								return FALSE;
+							}
 						}
 						session->learn_multiplier = strtod (arg, NULL);
 						break;
 					default:
 						r = snprintf (out_buf, sizeof (out_buf), "tokenizer is not defined" CRLF);
-						rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-						return;
+						if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+							return FALSE;
+						}
+						return TRUE;
 					}
 				}
 			}
@@ -558,29 +596,37 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 		if (!arg || *arg == '\0') {
 			msg_debug ("no statfile specified in weights command");
 			r = snprintf (out_buf, sizeof (out_buf), "weights command requires two arguments: statfile and message size" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 		}
 		arg = *(cmd_args + 1);
 		if (arg == NULL || *arg == '\0') {
 			msg_debug ("no message size specified in weights command");
 			r = snprintf (out_buf, sizeof (out_buf), "weights command requires two arguments: statfile and message size" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 		}
 		size = strtoul (arg, &err_str, 10);
 		if (err_str && *err_str != '\0') {
 			msg_debug ("message size is invalid: %s", arg);
 			r = snprintf (out_buf, sizeof (out_buf), "message size is invalid" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 		}
 
 		cl = g_hash_table_lookup (session->cfg->classifiers_symbols, *cmd_args);
 		if (cl == NULL) {
 			r = snprintf (out_buf, sizeof (out_buf), "statfile %s is not defined" CRLF, *cmd_args);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 
 		}
 		session->learn_classifier = cl;
@@ -591,8 +637,10 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 	case COMMAND_SYNC:
 		if (!process_sync_command (session, cmd_args)) {
 			r = snprintf (out_buf, sizeof (out_buf), "FAIL" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
-			return;
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
+			return TRUE;
 		}
 		break;
 	case COMMAND_HELP:
@@ -607,12 +655,15 @@ process_command (struct controller_command *cmd, char **cmd_args, struct control
 			"    stat - show different rspamd stat" CRLF 
 			"    counters - show rspamd counters" CRLF 
 			"    uptime - rspamd uptime" CRLF);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 		break;
 	case COMMAND_COUNTERS:
 		rspamd_hash_foreach (counters, counter_write_callback, session);
 		break;
 	}
+	return TRUE;
 }
 
 static                          gboolean
@@ -664,7 +715,9 @@ controller_read_socket (f_str_t * in, void *arg)
 			comp_list = g_completion_complete (comp, cmd, NULL);
 			switch (g_list_length (comp_list)) {
 			case 1:
-				process_command ((struct controller_command *)comp_list->data, &params[1], session);
+				if (! process_command ((struct controller_command *)comp_list->data, &params[1], session)) {
+					return FALSE;
+				}
 				break;
 			case 0:
 				if (!process_custom_command (cmd, &params[1], session)) {
@@ -708,7 +761,9 @@ controller_read_socket (f_str_t * in, void *arg)
 			free_task (task, FALSE);
 			session->state = STATE_REPLY;
 			r = snprintf (out_buf, sizeof (out_buf), "cannot process message" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 			return FALSE;
 		}
 		if ((s = g_hash_table_lookup (session->learn_classifier->opts, "header")) != NULL) {
@@ -805,7 +860,9 @@ controller_read_socket (f_str_t * in, void *arg)
 			free_task (task, FALSE);
 			session->state = STATE_REPLY;
 			r = snprintf (out_buf, sizeof (out_buf), "cannot process message" CRLF);
-			rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+				return FALSE;
+			}
 			return FALSE;
 		}
 
@@ -951,7 +1008,9 @@ accept_socket (int fd, short what, void *arg)
 	new_session->s = new_async_session (new_session->session_pool, free_session, new_session);
 
 	new_session->dispatcher = rspamd_create_dispatcher (nfd, BUFFER_LINE, controller_read_socket, controller_write_socket, controller_err_socket, io_tv, (void *)new_session);
-	rspamd_dispatcher_write (new_session->dispatcher, greetingbuf, strlen (greetingbuf), FALSE, FALSE);
+	if (! rspamd_dispatcher_write (new_session->dispatcher, greetingbuf, strlen (greetingbuf), FALSE, FALSE)) {
+		msg_warn ("cannot write greeting");
+	}
 }
 
 void
diff --git a/src/lmtp.c b/src/lmtp.c
index 385debfbb..47962ce93 100644
--- a/src/lmtp.c
+++ b/src/lmtp.c
@@ -147,10 +147,7 @@ lmtp_read_socket (f_str_t * in, void *arg)
 		r = process_message (lmtp->task);
 		r = process_filters (lmtp->task);
 		if (r == -1) {
-			task->last_error = "Filter processing error";
-			task->error_code = LMTP_FAILURE;
-			task->state = WRITE_ERROR;
-			lmtp_write_socket (lmtp);
+			return FALSE;
 		}
 		else if (r == 0) {
 			task->state = WAIT_FILTER;
@@ -262,7 +259,9 @@ accept_socket (int fd, short what, void *arg)
 	/* Set up dispatcher */
 	new_task->dispatcher = rspamd_create_dispatcher (nfd, BUFFER_LINE, lmtp_read_socket, lmtp_write_socket, lmtp_err_socket, &io_tv, (void *)lmtp);
 	new_task->dispatcher->peer_addr = new_task->client_addr.s_addr;
-	rspamd_dispatcher_write (lmtp->task->dispatcher, greetingbuf, strlen (greetingbuf), FALSE, FALSE);
+	if (! rspamd_dispatcher_write (lmtp->task->dispatcher, greetingbuf, strlen (greetingbuf), FALSE, FALSE)) {
+		msg_warn ("cannot write greeting");
+	}
 }
 
 /*
diff --git a/src/lmtp_proto.c b/src/lmtp_proto.c
index 20d02e4f9..c9a58a641 100644
--- a/src/lmtp_proto.c
+++ b/src/lmtp_proto.c
@@ -88,7 +88,7 @@ extract_mail (memory_pool_t * pool, f_str_t * line)
 	return match;
 }
 
-static void
+static gboolean
 out_lmtp_reply (struct worker_task *task, int code, char *rcode, char *msg)
 {
 	char                            outbuf[OUTBUFSIZ];
@@ -100,7 +100,10 @@ out_lmtp_reply (struct worker_task *task, int code, char *rcode, char *msg)
 	else {
 		r = snprintf (outbuf, OUTBUFSIZ, "%d %s %s\r\n", code, rcode, msg);
 	}
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+	if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE)) {
+		return FALSE;
+	}
+	return TRUE;
 }
 
 int
@@ -115,7 +118,7 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 		/* Search LHLO line */
 		if ((i = fstrstri (line, &lhlo_command)) == -1) {
 			msg_info ("LHLO expected but not found");
-			out_lmtp_reply (lmtp->task, LMTP_BAD_CMD, "5.0.0", "Need LHLO here");
+			(void)out_lmtp_reply (lmtp->task, LMTP_BAD_CMD, "5.0.0", "Need LHLO here");
 			return -1;
 		}
 		else {
@@ -130,7 +133,9 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 			/* Strlcpy makes string null terminated by design */
 			g_strlcpy (lmtp->task->helo, c, line->len - i + 1);
 			lmtp->state = LMTP_READ_FROM;
-			out_lmtp_reply (lmtp->task, LMTP_OK, "", "Ok");
+			if (! out_lmtp_reply (lmtp->task, LMTP_OK, "", "Ok")) {
+				return -1;
+			}
 			return 0;
 		}
 		break;
@@ -138,7 +143,7 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 		/* Search MAIL FROM: line */
 		if ((i = fstrstri (line, &mail_command)) == -1) {
 			msg_info ("MAIL expected but not found");
-			out_lmtp_reply (lmtp->task, LMTP_BAD_CMD, "5.0.0", "Need MAIL here");
+			(void)out_lmtp_reply (lmtp->task, LMTP_BAD_CMD, "5.0.0", "Need MAIL here");
 			return -1;
 		}
 		else {
@@ -148,7 +153,9 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 			fstr.len = line->len - i;
 			lmtp->task->from = extract_mail (lmtp->task->task_pool, &fstr);
 			lmtp->state = LMTP_READ_RCPT;
-			out_lmtp_reply (lmtp->task, LMTP_OK, "2.1.0", "Sender ok");
+			if (! out_lmtp_reply (lmtp->task, LMTP_OK, "2.1.0", "Sender ok")) {
+				return -1;
+			}
 			return 0;
 		}
 		break;
@@ -156,7 +163,7 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 		/* Search RCPT_TO: line */
 		if ((i = fstrstri (line, &rcpt_command)) == -1) {
 			msg_info ("RCPT expected but not found");
-			out_lmtp_reply (lmtp->task, LMTP_NO_RCPT, "5.5.4", "Need RCPT here");
+			(void)out_lmtp_reply (lmtp->task, LMTP_NO_RCPT, "5.5.4", "Need RCPT here");
 			return -1;
 		}
 		else {
@@ -168,13 +175,15 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 			if (*rcpt == '<' && *(rcpt + 1) == '>') {
 				/* Invalid or empty rcpt not allowed */
 				msg_info ("bad recipient");
-				out_lmtp_reply (lmtp->task, LMTP_NO_RCPT, "5.5.4", "Bad recipient");
+				(void)out_lmtp_reply (lmtp->task, LMTP_NO_RCPT, "5.5.4", "Bad recipient");
 				return -1;
 			}
 			/* Strlcpy makes string null terminated by design */
 			lmtp->task->rcpt = g_list_prepend (lmtp->task->rcpt, rcpt);
 			lmtp->state = LMTP_READ_DATA;
-			out_lmtp_reply (lmtp->task, LMTP_OK, "2.1.0", "Recipient ok");
+			if (! out_lmtp_reply (lmtp->task, LMTP_OK, "2.1.0", "Recipient ok")) {
+				return -1;
+			}
 			return 0;
 		}
 		break;
@@ -182,7 +191,7 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 		/* Search DATA line */
 		if ((i = fstrstri (line, &data_command)) == -1) {
 			msg_info ("DATA expected but not found");
-			out_lmtp_reply (lmtp->task, LMTP_BAD_CMD, "5.0.0", "Need DATA here");
+			(void)out_lmtp_reply (lmtp->task, LMTP_BAD_CMD, "5.0.0", "Need DATA here");
 			return -1;
 		}
 		else {
@@ -197,7 +206,9 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 			g_strlcpy (rcpt, c, line->len - i + 1);
 			lmtp->task->rcpt = g_list_prepend (lmtp->task->rcpt, rcpt);
 			lmtp->state = LMTP_READ_MESSAGE;
-			out_lmtp_reply (lmtp->task, LMTP_DATA, "", "Enter message, ending with \".\" on a line by itself");
+			if (! out_lmtp_reply (lmtp->task, LMTP_DATA, "", "Enter message, ending with \".\" on a line by itself")) {
+				return -1;
+			}
 			lmtp->task->msg = fstralloc (lmtp->task->task_pool, BUFSIZ);
 			return 0;
 		}
@@ -230,7 +241,9 @@ read_lmtp_input_line (struct rspamd_lmtp_proto *lmtp, f_str_t * line)
 		/* We have some input after reading dot, close connection as we have no currently support of multiply 
 		 * messages per session
 		 */
-		out_lmtp_reply (lmtp->task, LMTP_QUIT, "", "Bye");
+		if (! out_lmtp_reply (lmtp->task, LMTP_QUIT, "", "Bye")) {
+			return -1;
+		}
 		return 0;
 		break;
 	}
@@ -288,10 +301,14 @@ close_mta_connection (struct mta_callback_data *cd, gboolean is_success)
 {
 	cd->task->state = CLOSING_CONNECTION;
 	if (is_success) {
-		out_lmtp_reply (cd->task, LMTP_OK, "", "Delivery completed");
+		if (! out_lmtp_reply (cd->task, LMTP_OK, "", "Delivery completed")) {
+			return;
+		}
 	}
 	else {
-		out_lmtp_reply (cd->task, LMTP_FAILURE, "", "Delivery failure");
+		if (! out_lmtp_reply (cd->task, LMTP_FAILURE, "", "Delivery failure")) {
+			return;
+		}
 	}
 	rspamd_remove_dispatcher (cd->dispatcher);
 }
@@ -335,7 +352,9 @@ mta_read_socket (f_str_t * in, void *arg)
 		else {
 			r = snprintf (outbuf, sizeof (outbuf), "HELO %s" CRLF, hostbuf);
 		}
-		rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 		cd->state = LMTP_WANT_MAIL;
 		break;
 	case LMTP_WANT_MAIL:
@@ -345,7 +364,9 @@ mta_read_socket (f_str_t * in, void *arg)
 			return FALSE;
 		}
 		r = snprintf (outbuf, sizeof (outbuf), "MAIL FROM: <%s>" CRLF, cd->task->from);
-		rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 		cd->state = LMTP_WANT_RCPT;
 		break;
 	case LMTP_WANT_RCPT:
@@ -361,7 +382,9 @@ mta_read_socket (f_str_t * in, void *arg)
 			cur = g_list_next (cur);
 		}
 
-		rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 		cd->state = LMTP_WANT_DATA;
 		break;
 	case LMTP_WANT_DATA:
@@ -371,7 +394,9 @@ mta_read_socket (f_str_t * in, void *arg)
 			return FALSE;
 		}
 		r = snprintf (outbuf, sizeof (outbuf), "DATA" CRLF);
-		rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 		cd->state = LMTP_WANT_DOT;
 		break;
 	case LMTP_WANT_DOT:
@@ -382,10 +407,14 @@ mta_read_socket (f_str_t * in, void *arg)
 		}
 		c = g_mime_object_to_string ((GMimeObject *) cd->task->message);
 		r = strlen (c);
-		rspamd_dispatcher_write (cd->task->dispatcher, c, r, TRUE, TRUE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, c, r, TRUE, TRUE)) {
+			return FALSE;
+		}
 		memory_pool_add_destructor (cd->task->task_pool, (pool_destruct_func) g_free, c);
 		r = snprintf (outbuf, sizeof (outbuf), CRLF "." CRLF);
-		rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 		cd->state = LMTP_WANT_CLOSING;
 	case LMTP_WANT_CLOSING:
 		if (!parse_mta_str (in, cd)) {
@@ -641,7 +670,9 @@ write_lmtp_reply (struct rspamd_lmtp_proto *lmtp)
 
 	debug_task ("writing reply to client");
 	if (lmtp->task->error_code != 0) {
-		out_lmtp_reply (lmtp->task, lmtp->task->error_code, "", lmtp->task->last_error);
+		if (! out_lmtp_reply (lmtp->task, lmtp->task->error_code, "", lmtp->task->last_error)) {
+			return -1;
+		}
 	}
 	else {
 		/* Do delivery */
@@ -650,7 +681,9 @@ write_lmtp_reply (struct rspamd_lmtp_proto *lmtp)
 			return -1;
 		}
 		else if (r == 0) {
-			out_lmtp_reply (lmtp->task, LMTP_OK, "", "Delivery completed");
+			if (! out_lmtp_reply (lmtp->task, LMTP_OK, "", "Delivery completed")) {
+				return -1;
+			}
 		}
 		else {
 			return 1;
diff --git a/src/plugins/emails.c b/src/plugins/emails.c
index ed6702396..1b20b2742 100644
--- a/src/plugins/emails.c
+++ b/src/plugins/emails.c
@@ -192,7 +192,9 @@ emails_command_handler (struct worker_task *task)
 	outbuf[r++] = '\r';
 	outbuf[r++] = '\n';
 
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+	if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE)) {
+		return -1;
+	}
 	msg_info ("msg ok, id: <%s>, %d emails extracted", task->message_id, num);
 
 	return 0;
diff --git a/src/plugins/fuzzy_check.c b/src/plugins/fuzzy_check.c
index e557c0a6d..198cf08e4 100644
--- a/src/plugins/fuzzy_check.c
+++ b/src/plugins/fuzzy_check.c
@@ -446,12 +446,16 @@ fuzzy_learn_callback (int fd, short what, void *arg)
 		}
 		else if (buf[0] == 'O' && buf[1] == 'K') {
 			r = snprintf (buf, sizeof (buf), "OK" CRLF);
-			rspamd_dispatcher_write (session->session->dispatcher, buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->session->dispatcher, buf, r, FALSE, FALSE)) {
+				return;
+			}
 			goto ok;
 		}
 		else {
 			r = snprintf (buf, sizeof (buf), "ERR" CRLF);
-			rspamd_dispatcher_write (session->session->dispatcher, buf, r, FALSE, FALSE);
+			if (! rspamd_dispatcher_write (session->session->dispatcher, buf, r, FALSE, FALSE)) {
+				return;
+			}
 			goto ok;
 		}
 	}
@@ -465,7 +469,9 @@ fuzzy_learn_callback (int fd, short what, void *arg)
   err:
 	msg_err ("got error in IO with server %s:%d, %d, %s", session->server->name, session->server->port, errno, strerror (errno));
 	r = snprintf (buf, sizeof (buf), "Error" CRLF);
-	rspamd_dispatcher_write (session->session->dispatcher, buf, r, FALSE, FALSE);
+	if (! rspamd_dispatcher_write (session->session->dispatcher, buf, r, FALSE, FALSE)) {
+		return;
+	}
   ok:
 	remove_normal_event (session->session->s, fuzzy_learn_fin, session);
 }
@@ -576,7 +582,9 @@ fuzzy_process_handler (struct controller_session *session, f_str_t * in)
 		free_task (task, FALSE);
 		session->state = STATE_REPLY;
 		r = snprintf (out_buf, sizeof (out_buf), "cannot process message" CRLF);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+			msg_warn ("write error");
+		}
 		return;
 	}
 	else {
@@ -605,7 +613,9 @@ fuzzy_process_handler (struct controller_session *session, f_str_t * in)
 					msg_warn ("cannot connect to %s, %d, %s", selected->name, errno, strerror (errno));
 					session->state = STATE_REPLY;
 					r = snprintf (out_buf, sizeof (out_buf), "no hashes written" CRLF);
-					rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+					if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+						return;
+					}
 					free_task (task, FALSE);
 					return;
 				}
@@ -634,7 +644,9 @@ fuzzy_process_handler (struct controller_session *session, f_str_t * in)
 				/* Cannot write hash */
 				session->state = STATE_REPLY;
 				r = snprintf (out_buf, sizeof (out_buf), "cannot write fuzzy hash" CRLF);
-				rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+				if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+					return;
+				}
 				free_task (task, FALSE);
 				return;
 			}
@@ -646,7 +658,9 @@ fuzzy_process_handler (struct controller_session *session, f_str_t * in)
 	if (*saved == 0) {
 		session->state = STATE_REPLY;
 		r = snprintf (out_buf, sizeof (out_buf), "no hashes written" CRLF);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+			return;
+		}
 	}
 }
 
@@ -662,7 +676,9 @@ fuzzy_controller_handler (char **args, struct controller_session *session, int c
 	if (!arg || *arg == '\0') {
 		msg_info ("empty content length");
 		r = snprintf (out_buf, sizeof (out_buf), "fuzzy command requires length as argument" CRLF);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+			return;
+		}
 		session->state = STATE_REPLY;
 		return;
 	}
@@ -670,7 +686,9 @@ fuzzy_controller_handler (char **args, struct controller_session *session, int c
 	size = strtoul (arg, &err_str, 10);
 	if (errno != 0 || (err_str && *err_str != '\0')) {
 		r = snprintf (out_buf, sizeof (out_buf), "learn size is invalid" CRLF);
-		rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (session->dispatcher, out_buf, r, FALSE, FALSE)) {
+			return;
+		}
 		session->state = STATE_REPLY;
 		return;
 	}
diff --git a/src/plugins/surbl.c b/src/plugins/surbl.c
index 810b2fbe5..699bd79d1 100644
--- a/src/plugins/surbl.c
+++ b/src/plugins/surbl.c
@@ -867,9 +867,11 @@ urls_command_handler (struct worker_task *task)
 	outbuf[r++] = '\r';
 	outbuf[r++] = '\n';
 
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, TRUE);
-	msg_info ("msg ok, id: <%s>, %d urls extracted", task->message_id, num);
 	g_tree_destroy (url_tree);
+	if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, TRUE)) {
+		return -1;
+	}
+	msg_info ("msg ok, id: <%s>, %d urls extracted", task->message_id, num);
 
 	return 0;
 }
diff --git a/src/protocol.c b/src/protocol.c
index a49682b2e..7f2907f86 100644
--- a/src/protocol.c
+++ b/src/protocol.c
@@ -414,6 +414,7 @@ struct metric_callback_data {
 	char                           *log_buf;
 	int                             log_offset;
 	int                             log_size;
+	gboolean                        alive;
 };
 
 static void
@@ -438,7 +439,7 @@ write_hashes_to_log (struct worker_task *task, char *logbuf, int offset, int siz
 	}
 }
 
-static void
+static gboolean
 show_url_header (struct worker_task *task)
 {
 	int                             r = 0;
@@ -467,7 +468,9 @@ show_url_header (struct worker_task *task)
 			outbuf[r++] = '\r';
 			outbuf[r++] = '\n';
 			outbuf[r] = ' ';
-			rspamd_dispatcher_write (task->dispatcher, outbuf, r, TRUE, FALSE);
+			if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, TRUE, FALSE)) {
+				return FALSE;
+			}
 			r = 0;
 		}
 		/* Write url host to buf */
@@ -487,7 +490,7 @@ show_url_header (struct worker_task *task)
 		}
 		cur = g_list_next (cur);
 	}
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+	return rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
 }
 
 static void
@@ -500,6 +503,10 @@ metric_symbols_callback (gpointer key, gpointer value, void *user_data)
 	struct symbol                  *s = (struct symbol *)value;
 	GList                          *cur;
 
+	if (! cd->alive) {
+		return;
+	}
+
 	if (s->options) {
 		r = snprintf (outbuf, OUTBUFSIZ, "Symbol: %s; ", (char *)key);
 		cur = s->options;
@@ -523,10 +530,12 @@ metric_symbols_callback (gpointer key, gpointer value, void *user_data)
 	}
 	cd->log_offset += snprintf (cd->log_buf + cd->log_offset, cd->log_size - cd->log_offset, "%s,", (char *)key);
 
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+	if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE)) {
+		cd->alive = FALSE;
+	}
 }
 
-static void
+static gboolean
 show_metric_symbols (struct metric_result *metric_res, struct metric_callback_data *cd)
 {
 	int                             r = 0;
@@ -546,7 +555,9 @@ show_metric_symbols (struct metric_result *metric_res, struct metric_callback_da
 			cur = g_list_next (cur);
 		}
 		g_list_free (symbols);
-		rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (cd->task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 	}
 	else {
 		g_hash_table_foreach (metric_res->symbols, metric_symbols_callback, cd);
@@ -555,6 +566,8 @@ show_metric_symbols (struct metric_result *metric_res, struct metric_callback_da
 			cd->log_buf[--cd->log_offset] = '\0';
 		}
 	}
+
+	return TRUE;
 }
 
 
@@ -570,7 +583,9 @@ show_metric_result (gpointer metric_name, gpointer metric_value, void *user_data
 	int                             is_spam = 0;
 	double                          ms = 0, rs = 0;
 
-
+	if (! cd->alive) {
+		return;
+	}
 	if (metric_name == NULL || metric_value == NULL) {
 		m = g_hash_table_lookup (task->cfg->metrics, DEFAULT_METRIC);
         default_required_score = m->required_score;
@@ -653,10 +668,14 @@ show_metric_result (gpointer metric_name, gpointer metric_value, void *user_data
 #endif
 	}
 	else {
-		rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			cd->alive = FALSE;
+		}
 
 		if (task->cmd == CMD_SYMBOLS && metric_value != NULL) {
-			show_metric_symbols (metric_res, cd);
+			if (! show_metric_symbols (metric_res, cd)) {
+				cd->alive = FALSE;
+			}
 		}
 	}
 #ifdef HAVE_CLOCK_GETTIME
@@ -668,7 +687,7 @@ show_metric_result (gpointer metric_name, gpointer metric_value, void *user_data
 #endif
 }
 
-static void
+static gboolean
 show_messages (struct worker_task *task)
 {
 	int                             r = 0;
@@ -681,10 +700,10 @@ show_messages (struct worker_task *task)
 		cur = g_list_next (cur);
 	}
 
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+	return rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
 }
 
-static int
+static gboolean
 write_check_reply (struct worker_task *task)
 {
 	int                             r;
@@ -694,12 +713,15 @@ write_check_reply (struct worker_task *task)
 
 	r = snprintf (outbuf, sizeof (outbuf), "%s/%s 0 %s" CRLF, (task->proto == SPAMC_PROTO) ? SPAMD_REPLY_BANNER : RSPAMD_REPLY_BANNER,
 					task->proto_ver, "OK");
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, TRUE, FALSE);
+	if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, TRUE, FALSE)) {
+		return FALSE;
+	}
 
 	cd.task = task;
 	cd.log_buf = logbuf;
 	cd.log_offset = snprintf (logbuf, sizeof (logbuf), "msg ok, id: <%s>, ", task->message_id);
 	cd.log_size = sizeof (logbuf);
+	cd.alive = TRUE;
 
 	if (task->proto == SPAMC_PROTO) {
 		/* Ignore metrics, just write report for 'default' metric */
@@ -707,9 +729,15 @@ write_check_reply (struct worker_task *task)
 		if (metric_res == NULL) {
 			/* Implicit metric result */
 			show_metric_result (NULL, NULL, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 		else {
 			show_metric_result ((gpointer) "default", (gpointer) metric_res, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 	}
 	else {
@@ -718,23 +746,38 @@ write_check_reply (struct worker_task *task)
 		if (metric_res == NULL) {
 			/* Implicit metric result */
 			show_metric_result (NULL, NULL, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 		else {
 			show_metric_result ((gpointer) "default", (gpointer) metric_res, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 		g_hash_table_remove (task->results, "default");
 
 		/* Write result for each metric separately */
 		g_hash_table_foreach (task->results, show_metric_result, &cd);
+		if (!cd.alive) {
+			return FALSE;
+		}
 		/* Messages */
-		show_messages (task);
+		if (! show_messages (task)) {
+			return FALSE;
+		}
 		/* URL stat */
-		show_url_header (task);
+		if (! show_url_header (task)) {
+			return FALSE;
+		}
 	}
 	
 	write_hashes_to_log (task, logbuf, cd.log_offset, cd.log_size);
 	msg_info ("%s", logbuf);
-	rspamd_dispatcher_write (task->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+	if (! rspamd_dispatcher_write (task->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+		return FALSE;
+	}
 
 	task->worker->srv->stat->messages_scanned++;
 	if (default_score >= default_required_score) {
@@ -744,10 +787,10 @@ write_check_reply (struct worker_task *task)
 		task->worker->srv->stat->messages_ham ++;
 	}
 
-	return 0;
+	return TRUE;
 }
 
-static int
+static gboolean
 write_process_reply (struct worker_task *task)
 {
 	int                             r;
@@ -764,6 +807,7 @@ write_process_reply (struct worker_task *task)
 	cd.log_buf = logbuf;
 	cd.log_offset = snprintf (logbuf, sizeof (logbuf), "msg ok, id: <%s>, ", task->message_id);
 	cd.log_size = sizeof (logbuf);
+	cd.alive = TRUE;
 
 	if (task->proto == SPAMC_PROTO) {
 		/* Ignore metrics, just write report for 'default' metric */
@@ -771,9 +815,15 @@ write_process_reply (struct worker_task *task)
 		if (metric_res == NULL) {
 			/* Implicit metric result */
 			show_metric_result (NULL, NULL, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 		else {
 			show_metric_result ((gpointer) "default", (gpointer) metric_res, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 	}
 	else {
@@ -782,24 +832,40 @@ write_process_reply (struct worker_task *task)
 		if (metric_res == NULL) {
 			/* Implicit metric result */
 			show_metric_result (NULL, NULL, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 		else {
 			show_metric_result ((gpointer) "default", (gpointer) metric_res, (void *)&cd);
+			if (! cd.alive) {
+				return FALSE;
+			}
 		}
 		g_hash_table_remove (task->results, "default");
 
 		/* Write result for each metric separately */
 		g_hash_table_foreach (task->results, show_metric_result, &cd);
+		if (! cd.alive) {
+			return FALSE;
+		}
 		/* Messages */
-		show_messages (task);
+		if (! show_messages (task)) {
+			return FALSE;
+		}
 	}
 	write_hashes_to_log (task, logbuf, cd.log_offset, cd.log_size);
 	msg_info ("%s", logbuf);
 
 	outmsg = g_mime_object_to_string (GMIME_OBJECT (task->message));
+	memory_pool_add_destructor (task->task_pool, (pool_destruct_func) g_free, outmsg);
 
-	rspamd_dispatcher_write (task->dispatcher, outbuf, r, TRUE, FALSE);
-	rspamd_dispatcher_write (task->dispatcher, outmsg, strlen (outmsg), FALSE, TRUE);
+	if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, TRUE, FALSE)) {
+		return FALSE;
+	}
+	if (! rspamd_dispatcher_write (task->dispatcher, outmsg, strlen (outmsg), FALSE, TRUE)) {
+		return FALSE;
+	}
 
 	task->worker->srv->stat->messages_scanned++;
 	if (default_score >= default_required_score) {
@@ -809,12 +875,10 @@ write_process_reply (struct worker_task *task)
 		task->worker->srv->stat->messages_ham ++;
 	}
 
-	memory_pool_add_destructor (task->task_pool, (pool_destruct_func) g_free, outmsg);
-
-	return 0;
+	return TRUE;
 }
 
-int
+gboolean
 write_reply (struct worker_task *task)
 {
 	int                             r;
@@ -834,7 +898,9 @@ write_reply (struct worker_task *task)
 			debug_task ("writing error: %s", outbuf);
 		}
 		/* Write to bufferevent error message */
-		rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+		if (! rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE)) {
+			return FALSE;
+		}
 	}
 	else {
 		switch (task->cmd) {
@@ -850,19 +916,19 @@ write_reply (struct worker_task *task)
 		case CMD_SKIP:
 			r = snprintf (outbuf, sizeof (outbuf), "%s/%s 0 %s" CRLF, 
 					(task->proto == SPAMC_PROTO) ? SPAMD_REPLY_BANNER : RSPAMD_REPLY_BANNER, task->proto_ver, SPAMD_OK);
-			rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+			return rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
 			break;
 		case CMD_PING:
 			r = snprintf (outbuf, sizeof (outbuf), "%s/%s 0 PONG" CRLF, 
 					(task->proto == SPAMC_PROTO) ? SPAMD_REPLY_BANNER : RSPAMD_REPLY_BANNER, task->proto_ver);
-			rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
+			return rspamd_dispatcher_write (task->dispatcher, outbuf, r, FALSE, FALSE);
 			break;
 		case CMD_OTHER:
 			return task->custom_cmd->func (task);
 		}
 	}
 
-	return 0;
+	return FALSE;
 }
 
 void
diff --git a/src/protocol.h b/src/protocol.h
index 4c12cc481..d45e5c555 100644
--- a/src/protocol.h
+++ b/src/protocol.h
@@ -64,7 +64,7 @@ int read_rspamd_input_line (struct worker_task *task, f_str_t *line);
  * @param task task object
  * @return 0 if we wrote reply and -1 if there was some error
  */
-int write_reply (struct worker_task *task);
+gboolean write_reply (struct worker_task *task) G_GNUC_WARN_UNUSED_RESULT;
 
 
 /**
diff --git a/src/smtp.c b/src/smtp.c
index f630c2428..f2c085aba 100644
--- a/src/smtp.c
+++ b/src/smtp.c
@@ -316,7 +316,9 @@ smtp_send_upstream_message (struct smtp_session *session)
 err:
 	session->error = SMTP_ERROR_FILE;
 	session->state = SMTP_STATE_CRITICAL_ERROR;
-	rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+	if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+		return FALSE;
+	}
 	destroy_session (session->s);
 	return FALSE;
 }
@@ -405,7 +407,9 @@ process_smtp_data (struct smtp_session *session)
 err:
 	session->error = SMTP_ERROR_FILE;
 	session->state = SMTP_STATE_CRITICAL_ERROR;
-	rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+	if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+		return FALSE;
+	}
 	destroy_session (session->s);
 	return FALSE;
 }
@@ -435,7 +439,9 @@ smtp_read_socket (f_str_t * in, void *arg)
 				if (session->errors > session->ctx->max_errors) {
 					session->error = SMTP_ERROR_LIMIT;
 					session->state = SMTP_STATE_CRITICAL_ERROR;
-					rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+					if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+						return FALSE;
+					}
 					destroy_session (session->s);
 					return FALSE;
 				}
@@ -454,7 +460,9 @@ smtp_read_socket (f_str_t * in, void *arg)
 				msg_err ("cannot write to temp file: %s", strerror (errno));
 				session->error = SMTP_ERROR_FILE;
 				session->state = SMTP_STATE_CRITICAL_ERROR;
-				rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+					return FALSE;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -496,7 +504,9 @@ smtp_write_socket (void *arg)
 
 	if (session->state == SMTP_STATE_CRITICAL_ERROR) {
 		if (session->error != NULL) {
-			rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+			if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+				return FALSE;
+			}
 		}
 		destroy_session (session->s);
 		return FALSE;
@@ -540,8 +550,12 @@ smtp_write_socket (void *arg)
 				msg_info ("%s", logbuf);
 
 				if (is_spam) {
-					rspamd_dispatcher_write (session->dispatcher, session->ctx->reject_message, 0, FALSE, TRUE);
-					rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+					if (! rspamd_dispatcher_write (session->dispatcher, session->ctx->reject_message, 0, FALSE, TRUE)) {
+						return FALSE;
+					}
+					if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+						return FALSE;
+					}
 					destroy_session (session->s);
 					return FALSE;
 				}
@@ -550,13 +564,17 @@ smtp_write_socket (void *arg)
 		}
 		else {
 			if (session->error != NULL) {
-				rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+					return FALSE;
+				}
 			}
 		}
 	}
 	else {
 		if (session->error != NULL) {
-			rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+			if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+				return FALSE;
+			}
 		}
 	}
 	
@@ -579,12 +597,16 @@ smtp_err_socket (GError * err, void *arg)
 /*
  * Write greeting to client
  */
-static void
+static gboolean
 write_smtp_greeting (struct smtp_session *session)
 {
 	if (session->ctx->smtp_banner) {
-		rspamd_dispatcher_write (session->dispatcher, session->ctx->smtp_banner, 0, FALSE, TRUE);
+		if (! rspamd_dispatcher_write (session->dispatcher, session->ctx->smtp_banner, 0, FALSE, TRUE)) {
+			return FALSE;
+		}
 	}
+
+	return TRUE;
 }
 
 /*
@@ -601,7 +623,7 @@ smtp_delay_handler (int fd, short what, void *arg)
 	}
 	else {
 		session->state = SMTP_STATE_CRITICAL_ERROR;
-		smtp_write_socket (session);
+		(void)smtp_write_socket (session);
 	}
 }
 
diff --git a/src/smtp_proto.c b/src/smtp_proto.c
index 06eed5cb0..f0669198c 100644
--- a/src/smtp_proto.c
+++ b/src/smtp_proto.c
@@ -402,8 +402,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				/* XXX: assume upstream errors as critical errors */
 				session->state = SMTP_STATE_CRITICAL_ERROR;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -437,8 +441,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				/* XXX: assume upstream errors as critical errors */
 				session->state = SMTP_STATE_CRITICAL_ERROR;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -463,8 +471,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				/* XXX: assume upstream errors as critical errors */
 				session->state = SMTP_STATE_CRITICAL_ERROR;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -483,8 +495,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				/* XXX: assume upstream errors as critical errors */
 				session->state = SMTP_STATE_CRITICAL_ERROR;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -503,8 +519,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				session->error = memory_pool_alloc (session->pool, in->len + 1);
 				g_strlcpy (session->error, in->begin, in->len + 1);
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				if (session->cur_rcpt) {
 					session->rcpt = g_list_delete_link (session->rcpt, session->cur_rcpt);
 				}
@@ -520,7 +540,9 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 					r = snprintf (outbuf, sizeof (outbuf), "RCPT TO: ");
 					r += smtp_upstream_write_list (session->cur_rcpt, outbuf + r, sizeof (outbuf) - r);
 					session->cur_rcpt = g_list_next (session->cur_rcpt);
-					rspamd_dispatcher_write (session->upstream_dispatcher, outbuf, r, FALSE, FALSE);
+					if (! rspamd_dispatcher_write (session->upstream_dispatcher, outbuf, r, FALSE, FALSE)) {
+						goto err;
+					}
 				}
 				else {
 					session->upstream_state = SMTP_STATE_DATA;
@@ -529,8 +551,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				session->error = memory_pool_alloc (session->pool, in->len + 1);
 				g_strlcpy (session->error, in->begin, in->len + 1);
 				/* Write to client */
-				rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, in->len, FALSE, TRUE)) {
+					goto err;
+				} 
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				if (session->state == SMTP_STATE_WAIT_UPSTREAM) {
 					rspamd_dispatcher_restore (session->dispatcher);
 					session->state = SMTP_STATE_RCPT;
@@ -545,8 +571,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				/* XXX: assume upstream errors as critical errors */
 				session->state = SMTP_STATE_CRITICAL_ERROR;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -565,14 +595,18 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 					session->error = SMTP_ERROR_FILE;
 					session->state = SMTP_STATE_CRITICAL_ERROR;
 					rspamd_dispatcher_restore (session->dispatcher);
-					rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+					if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+						goto err;
+					}
 					destroy_session (session->s);
 					return FALSE;
 				}
 				session->state = SMTP_STATE_AFTER_DATA;
 				session->error = SMTP_ERROR_DATA_OK;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
+				if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+					goto err;
+				}
 				rspamd_dispatcher_pause (session->upstream_dispatcher);
 				rspamd_set_dispatcher_policy (session->dispatcher, BUFFER_LINE, 0);
 				session->dispatcher->strip_eol = FALSE;
@@ -584,9 +618,15 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 			g_strlcpy (session->error, in->begin, in->len + 1);
 			session->state = SMTP_STATE_DATA;
 			rspamd_dispatcher_restore (session->dispatcher);
-			rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
-			rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
-			rspamd_dispatcher_write (session->upstream_dispatcher, "QUIT" CRLF, sizeof ("QUIT" CRLF) - 1, FALSE, TRUE);
+			if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+				goto err;
+			}
+			if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+				goto err;
+			}
+			if (! rspamd_dispatcher_write (session->upstream_dispatcher, "QUIT" CRLF, sizeof ("QUIT" CRLF) - 1, FALSE, TRUE)) {
+				goto err;
+			}
 			session->upstream_state = SMTP_STATE_END;
 			return TRUE;
 			break;
@@ -598,8 +638,12 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 				/* XXX: assume upstream errors as critical errors */
 				session->state = SMTP_STATE_CRITICAL_ERROR;
 				rspamd_dispatcher_restore (session->dispatcher);
-				rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
-				rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+				if (!rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+					goto err;
+				}
+				if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+					goto err;
+				}
 				destroy_session (session->s);
 				return FALSE;
 			}
@@ -612,13 +656,20 @@ smtp_upstream_read_socket (f_str_t * in, void *arg)
 			msg_err ("got upstream reply at unexpected state: %d, reply: %V", session->upstream_state, in);
 			session->state = SMTP_STATE_CRITICAL_ERROR;
 			rspamd_dispatcher_restore (session->dispatcher);
-			rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
-			rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+			if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+				goto err;
+			}
+			if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+				goto err;
+			}
 			destroy_session (session->s);
 			return FALSE;
 	}
 
 	return TRUE;
+err:
+	msg_warn ("write error occured");
+	return FALSE;
 }
 
 void 
@@ -631,8 +682,12 @@ smtp_upstream_err_socket (GError *err, void *arg)
 	session->state = SMTP_STATE_CRITICAL_ERROR;
 	/* XXX: assume upstream errors as critical errors */
 	rspamd_dispatcher_restore (session->dispatcher);
-	rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE);
-	rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE);
+	if (! rspamd_dispatcher_write (session->dispatcher, session->error, 0, FALSE, TRUE)) {
+		return;
+	}
+	if (! rspamd_dispatcher_write (session->dispatcher, CRLF, sizeof (CRLF) - 1, FALSE, TRUE)) {
+		return;
+	}
 	upstream_fail (&session->upstream->up, session->session_time);
 	destroy_session (session->s);
 }
@@ -643,7 +698,9 @@ smtp_upstream_finalize_connection (gpointer data)
 	struct smtp_session            *session = data;
 	
 	if (session->state != SMTP_STATE_CRITICAL_ERROR) {
-		rspamd_dispatcher_write (session->upstream_dispatcher, "QUIT" CRLF, 0, FALSE, TRUE);
+		if (! rspamd_dispatcher_write (session->upstream_dispatcher, "QUIT" CRLF, 0, FALSE, TRUE)) {
+			msg_warn ("cannot send correctly closing message to upstream");
+		}
 	}
 	rspamd_remove_dispatcher (session->upstream_dispatcher);
 	session->upstream_dispatcher = NULL;
diff --git a/src/worker.c b/src/worker.c
index 5e803cc78..13880bdfa 100644
--- a/src/worker.c
+++ b/src/worker.c
@@ -158,7 +158,10 @@ fin_custom_filters (struct worker_task *task)
 		if (filt->after_connect) {
 			filt->after_connect (&output, &log, curd->data);
 			if (output != NULL) {
-				rspamd_dispatcher_write (task->dispatcher, output, strlen (output), FALSE, FALSE);
+				if (! rspamd_dispatcher_write (task->dispatcher, output, strlen (output), FALSE, FALSE)) {
+					g_free (output);
+					return;
+				}
 				g_free (output);
 			}
 			if (log != NULL) {
@@ -190,7 +193,10 @@ parse_line_custom (struct worker_task *task, f_str_t *in)
 				res = FALSE;
 			}
 			if (output != NULL) {
-				rspamd_dispatcher_write (task->dispatcher, output, strlen (output), FALSE, FALSE);
+				if (! rspamd_dispatcher_write (task->dispatcher, output, strlen (output), FALSE, FALSE)) {
+					g_free (output);
+					return FALSE;
+				}
 				g_free (output);
 			}
 			if (curd->next) {
@@ -349,7 +355,9 @@ write_socket (void *arg)
 
 	switch (task->state) {
 	case WRITE_REPLY:
-		write_reply (task);
+		if (! write_reply (task)) {
+			return FALSE;
+		}
 		if (is_custom) {
 			fin_custom_filters (task);
 		}
@@ -357,7 +365,9 @@ write_socket (void *arg)
 		return FALSE;
 		break;
 	case WRITE_ERROR:
-		write_reply (task);
+		if (! write_reply (task)) {
+			return FALSE;
+		}
 		if (is_custom) {
 			fin_custom_filters (task);
 		}