From f95981a276aa0dbd03f51190949fa8c5db74d8ff Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@meshlink.io>
Date: Thu, 21 May 2020 00:13:50 +0200
Subject: [PATCH] Limit the size of the fd read buffer in channel_poll().

---
 src/meshlink.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/meshlink.c b/src/meshlink.c
index 14ff7155..e50be188 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -3675,6 +3675,11 @@ static void channel_poll(struct utcp_connection *connection, size_t len) {
 		if(aio->data) {
 			sent = utcp_send(connection, (char *)aio->data + aio->done, todo);
 		} else {
+			/* Limit the amount we read at once to avoid stack overflows */
+			if(todo > 65536) {
+				todo = 65536;
+			}
+
 			char buf[todo];
 			ssize_t result = read(aio->fd, buf, todo);
 
-- 
2.39.5