From b27902e5769e04c33d33cbe36e772419cf5ddeec Mon Sep 17 00:00:00 2001 From: Dmitry Volyntsev Date: Mon, 2 Mar 2020 20:07:36 +0300 Subject: [PATCH] Fixed premature background subrequest finalization. When "aio" or "aio threads" is used while processing the response body of an in-memory background subrequest, the subrequest could be finalized with an aio operation still in progress. Upon aio completion either parent request is woken or the old r->write_event_handler is called again. The latter may result in request errors. In either case post_subrequest handler is never called with the full response body, which is typically expected when using in-memory subrequests. Currently in nginx background subrequests are created by the upstream module and the mirror module. The issue does not manifest itself with these subrequests because they are header-only. But it can manifest itself with third-party modules which create in-memory background subrequests. --- src/http/ngx_http_request.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c index bb69e71d0..5fcaa2c33 100644 --- a/src/http/ngx_http_request.c +++ b/src/http/ngx_http_request.c @@ -2490,6 +2490,15 @@ ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc) if (r != r->main) { clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module); + if (r->buffered || r->postponed) { + + if (ngx_http_set_write_handler(r) != NGX_OK) { + ngx_http_terminate_request(r, 0); + } + + return; + } + if (r->background) { if (!r->logged) { if (clcf->log_subrequest) { @@ -2509,15 +2518,6 @@ ngx_http_finalize_request(ngx_http_request_t *r, ngx_int_t rc) return; } - if (r->buffered || r->postponed) { - - if (ngx_http_set_write_handler(r) != NGX_OK) { - ngx_http_terminate_request(r, 0); - } - - return; - } - pr = r->parent; if (r == c->data) {