From fecb145a7170b708e2e03e50a39a04b2eada94d7 Mon Sep 17 00:00:00 2001 From: "J. Nick Koston" Date: Wed, 11 Feb 2026 17:42:18 -0600 Subject: [PATCH] [web_server_idf] Revert multipart upload buffer back to heap to fix httpd stack overflow (#13941) --- esphome/components/web_server_idf/web_server_idf.cpp | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/esphome/components/web_server_idf/web_server_idf.cpp b/esphome/components/web_server_idf/web_server_idf.cpp index 2e07fb6e0a..d7d6f90355 100644 --- a/esphome/components/web_server_idf/web_server_idf.cpp +++ b/esphome/components/web_server_idf/web_server_idf.cpp @@ -881,12 +881,12 @@ esp_err_t AsyncWebServer::handle_multipart_upload_(httpd_req_t *r, const char *c } }); - // Process data - use stack buffer to avoid heap allocation - char buffer[MULTIPART_CHUNK_SIZE]; + // Use heap buffer - 1460 bytes is too large for the httpd task stack + auto buffer = std::make_unique(MULTIPART_CHUNK_SIZE); size_t bytes_since_yield = 0; for (size_t remaining = r->content_len; remaining > 0;) { - int recv_len = httpd_req_recv(r, buffer, std::min(remaining, MULTIPART_CHUNK_SIZE)); + int recv_len = httpd_req_recv(r, buffer.get(), std::min(remaining, MULTIPART_CHUNK_SIZE)); if (recv_len <= 0) { httpd_resp_send_err(r, recv_len == HTTPD_SOCK_ERR_TIMEOUT ? HTTPD_408_REQ_TIMEOUT : HTTPD_400_BAD_REQUEST, @@ -894,7 +894,7 @@ esp_err_t AsyncWebServer::handle_multipart_upload_(httpd_req_t *r, const char *c return recv_len == HTTPD_SOCK_ERR_TIMEOUT ? ESP_ERR_TIMEOUT : ESP_FAIL; } - if (reader->parse(buffer, recv_len) != static_cast(recv_len)) { + if (reader->parse(buffer.get(), recv_len) != static_cast(recv_len)) { ESP_LOGW(TAG, "Multipart parser error"); httpd_resp_send_err(r, HTTPD_400_BAD_REQUEST, nullptr); return ESP_FAIL;