# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1392730240 -14400
# Node ID 7586e7b2dbe9d9999014a99fe40e58c2e90b9cf5
# Parent  e280ece17020ada6a294275fe2a5e91674483712
Upstream: ngx_post_event() instead of upgraded call (ticket #503).

If a request is finalized in the first call to the
ngx_http_upstream_process_upgraded() function, e.g., because upstream
server closed the connection for some reason, in the second call
the u->peer.connection pointer will be null, resulting in segmentation
fault.

Fix is to avoid second direct call, and post event instead.  This ensures
that ngx_http_upstream_process_upgraded() won't be called again if
a request is finalized.

diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -2557,7 +2557,9 @@ ngx_http_upstream_upgrade(ngx_http_reque
     if (u->peer.connection->read->ready
         || u->buffer.pos != u->buffer.last)
     {
+        ngx_post_event(c->read, &ngx_posted_events);
         ngx_http_upstream_process_upgraded(r, 1, 1);
+        return;
     }
 
     ngx_http_upstream_process_upgraded(r, 0, 1);