diff --git a/socket-handler.c b/socket-handler.c
index b10615b..79e1641 100644
--- a/socket-handler.c
+++ b/socket-handler.c
@@ -19,6 +19,7 @@
 #include <assert.h>
 #include <err.h>
 #include <errno.h>
+#include <limits.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -112,9 +113,13 @@
 static ssize_t send_all(struct client *client, void *buf, size_t len,
 			bool block)
 {
-	int fd, rc, flags;
+	int fd, flags;
+	ssize_t rc;
 	size_t pos;
 
+	if (len > SSIZE_MAX)
+		return -EINVAL;
+
 	fd = client->fd;
 
 	flags = MSG_NOSIGNAL;
@@ -139,7 +144,7 @@
 			return -1;
 	}
 
-	return pos;
+	return (ssize_t)pos;
 }
 
 /* Drain the queue to the socket and update the queue buffer. If force_len is
@@ -189,7 +194,8 @@
 						       size_t force_len)
 {
 	struct client *client = arg;
-	int rc, len;
+	size_t len;
+	int rc;
 
 	len = ringbuffer_len(client->rbc);
 	if (!force_len && (len < SOCKET_HANDLER_PKT_SIZE)) {
@@ -238,7 +244,7 @@
 	struct socket_handler *sh = to_socket_handler(handler);
 	struct client *client = data;
 	uint8_t buf[4096];
-	int rc;
+	ssize_t rc;
 
 	if (events & POLLIN) {
 		rc = recv(client->fd, buf, sizeof(buf), MSG_DONTWAIT);