From 0b01f9fc42aa7e848dfbab78500d8ba97778dc29 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 20 Mar 2026 13:57:51 -1000
Subject: [PATCH] [web_server] Increase httpd task stack size to prevent stack
 overflow (#14997)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 esphome/components/web_server_idf/web_server_idf.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/esphome/components/web_server_idf/web_server_idf.cpp b/esphome/components/web_server_idf/web_server_idf.cpp
index 60816fc6dd..fb0c17c854 100644
--- a/esphome/components/web_server_idf/web_server_idf.cpp
+++ b/esphome/components/web_server_idf/web_server_idf.cpp
@@ -121,7 +121,10 @@ void AsyncWebServer::begin() {
   if (this->server_) {
     this->end();
   }
+  // Default httpd stack is defined by ESP-IDF. Increase to accommodate SerializationBuffer's
+  // 640-byte stack buffer used by web_server JSON request handlers.
   httpd_config_t config = HTTPD_DEFAULT_CONFIG();
+  config.stack_size = config.stack_size + 256;
   config.server_port = this->port_;
   config.uri_match_fn = [](const char * /*unused*/, const char * /*unused*/, size_t /*unused*/) { return true; };
   // Always enable LRU purging to handle socket exhaustion gracefully.