From eae2b2fdf15c52f058c0c08763a5c373997d0535 Mon Sep 17 00:00:00 2001
From: Maxim Dounin <mdounin@mdounin.ru>
Date: Mon, 10 Aug 2020 18:52:34 +0300
Subject: [PATCH] SSL: disabled sending shutdown after ngx_http_test_reading().
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Sending shutdown when ngx_http_test_reading() detects the connection is
closed can result in "SSL_shutdown() failed (SSL: ... bad write retry)"
critical log messages if there are blocked writes.

Fix is to avoid sending shutdown via the c->ssl->no_send_shutdown flag,
similarly to how it is done in ngx_http_keepalive_handler() for kqueue
when pending EOF is detected.

Reported by Jan Prachař
(http://mailman.nginx.org/pipermail/nginx-devel/2018-December/011702.html).
---
 src/http/ngx_http_request.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 257c4064b..f80785d8f 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -2992,6 +2992,12 @@ closed:
         rev->error = 1;
     }
 
+#if (NGX_HTTP_SSL)
+    if (c->ssl) {
+        c->ssl->no_send_shutdown = 1;
+    }
+#endif
+
     ngx_log_error(NGX_LOG_INFO, c->log, err,
                   "client prematurely closed connection");