From 052a077a35422f1690365707f19733946573de4d Mon Sep 17 00:00:00 2001
From: Erik Olof Gunnar Andersson <me@eandersson.net>
Date: Thu, 10 Oct 2024 20:15:55 +0200
Subject: [PATCH] Protect against a empty or tiny / invalid file

---
 main/http_server/http_server.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/main/http_server/http_server.c b/main/http_server/http_server.c
index 2c5afb9a..12b72485 100644
--- a/main/http_server/http_server.c
+++ b/main/http_server/http_server.c
@@ -499,6 +499,12 @@ esp_err_t POST_WWW_update(httpd_req_t * req)
         return ESP_OK;
     }
 
+    // Don't attempt to write anything way too small to the partition
+    if (remaining < 32768) {
+        httpd_resp_send_err(req, HTTPD_400_BAD_REQUEST, "File provided is too small, likely corrupt or invalid");
+        return ESP_OK;
+    }
+
     // Erase the entire www partition before writing
     ESP_ERROR_CHECK(esp_partition_erase_range(www_partition, 0, www_partition->size));