changeset 8007:011f5ebdb928

HTTP/2: fixed closed_nodes overflow (ticket #1708). With large http2_max_concurrent_streams or http2_max_concurrent_pushes, more than 255 ngx_http_v2_node_t structures might be allocated, eventually leading to h2c->closed_nodes overflow when closing corresponding streams. This will in turn result in additional allocations in ngx_http_v2_get_node_by_id(). While mostly harmless, it can result in excessive memory usage by a HTTP/2 connection, notably in configurations with many keepalive_requests allowed. Fix is to use ngx_uint_t for h2c->closed_nodes instead of unsigned:8.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 03 Feb 2022 22:46:01 +0300
parents 32b0ba4855a6
children 1add55d23652
files src/http/v2/ngx_http_v2.h
diffstat 1 files changed, 1 insertions(+), 1 deletions(-) [+]
line wrap: on
line diff
--- a/src/http/v2/ngx_http_v2.h
+++ b/src/http/v2/ngx_http_v2.h
@@ -153,12 +153,12 @@ struct ngx_http_v2_connection_s {
     ngx_queue_t                      dependencies;
     ngx_queue_t                      closed;
 
+    ngx_uint_t                       closed_nodes;
     ngx_uint_t                       last_sid;
     ngx_uint_t                       last_push;
 
     time_t                           lingering_time;
 
-    unsigned                         closed_nodes:8;
     unsigned                         settings_ack:1;
     unsigned                         table_update:1;
     unsigned                         blocked:1;