HTTP/2: limited number of PRIORITY frames.
Fixed excessive CPU usage caused by a peer that continuously shuffles
priority of streams. Fix is to limit the number of PRIORITY frames.
Ruslan Ermilov
2 years ago
| 272 | 272 | h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module); |
| 273 | 273 | |
| 274 | 274 | h2c->concurrent_pushes = h2scf->concurrent_pushes; |
| 275 | h2c->priority_limit = h2scf->concurrent_streams; | |
| 275 | 276 | |
| 276 | 277 | h2c->pool = ngx_create_pool(h2scf->pool_size, h2c->connection->log); |
| 277 | 278 | if (h2c->pool == NULL) { |
| 1801 | 1802 | h2c->state.length); |
| 1802 | 1803 | |
| 1803 | 1804 | return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR); |
| 1805 | } | |
| 1806 | ||
| 1807 | if (--h2c->priority_limit == 0) { | |
| 1808 | ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0, | |
| 1809 | "client sent too many PRIORITY frames"); | |
| 1810 | ||
| 1811 | return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_ENHANCE_YOUR_CALM); | |
| 1804 | 1812 | } |
| 1805 | 1813 | |
| 1806 | 1814 | if (end - pos < NGX_HTTP_V2_PRIORITY_SIZE) { |
| 3118 | 3126 | } else { |
| 3119 | 3127 | h2c->processing++; |
| 3120 | 3128 | } |
| 3129 | ||
| 3130 | h2c->priority_limit += h2scf->concurrent_streams; | |
| 3121 | 3131 | |
| 3122 | 3132 | return stream; |
| 3123 | 3133 | } |