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diff --git a/src/http/v2/ngx_http_v2.c b/src/http/v2/ngx_http_v2.c
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index 3b7f892..0aaea47 100644
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--- a/src/http/v2/ngx_http_v2.c
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+++ b/src/http/v2/ngx_http_v2.c
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@@ -275,6 +275,7 @@ ngx_http_v2_init(ngx_event_t *rev)
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     h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module);
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     h2c->concurrent_pushes = h2scf->concurrent_pushes;
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+    h2c->priority_limit = h2scf->concurrent_streams;
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     h2c->pool = ngx_create_pool(h2scf->pool_size, h2c->connection->log);
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     if (h2c->pool == NULL) {
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@@ -1798,6 +1799,13 @@ ngx_http_v2_state_priority(ngx_http_v2_connection_t *h2c, u_char *pos,
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         return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_SIZE_ERROR);
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     }
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+    if (--h2c->priority_limit == 0) {
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+        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
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+                      "client sent too many PRIORITY frames");
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+
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+        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_ENHANCE_YOUR_CALM);
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+    }
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+
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     if (end - pos < NGX_HTTP_V2_PRIORITY_SIZE) {
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         return ngx_http_v2_state_save(h2c, pos, end,
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                                       ngx_http_v2_state_priority);
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@@ -3112,6 +3120,8 @@ ngx_http_v2_create_stream(ngx_http_v2_connection_t *h2c, ngx_uint_t push)
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         h2c->processing++;
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     }
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+    h2c->priority_limit += h2scf->concurrent_streams;
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+
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     return stream;
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 }
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diff --git a/src/http/v2/ngx_http_v2.h b/src/http/v2/ngx_http_v2.h
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index 715b7d3..69d55d1 100644
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--- a/src/http/v2/ngx_http_v2.h
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+++ b/src/http/v2/ngx_http_v2.h
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@@ -122,6 +122,7 @@ struct ngx_http_v2_connection_s {
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     ngx_uint_t                       processing;
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     ngx_uint_t                       frames;
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     ngx_uint_t                       idle;
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+    ngx_uint_t                       priority_limit;
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     ngx_uint_t                       pushing;
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     ngx_uint_t                       concurrent_pushes;