Apply CVE-2023-44487 patch to NGINX

This follows Alpine Linux's lead
(https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/53162)
and applies the CVE patch to NGINX v1.24.0.

Changelog: security

Author: stanhu

config/patches/nginx/CVE-2023-44487.patch

@@ -0,0 +1,71 @@
+
+# HG changeset patch
+# User Maxim Dounin <[email protected]>
+# Date 1696940019 -10800
+# Node ID cdda286c0f1b4b10f30d4eb6a63fefb9b8708ecc
+# Parent  3db945fda515014d220151046d02f3960bcfca0a
+HTTP/2: per-iteration stream handling limit.
+
+To ensure that attempts to flood servers with many streams are detected
+early, a limit of no more than 2 * max_concurrent_streams new streams per one
+event loop iteration was introduced.  This limit is applied even if
+max_concurrent_streams is not yet reached - for example, if corresponding
+streams are handled synchronously or reset.
+
+Further, refused streams are now limited to maximum of max_concurrent_streams
+and 100, similarly to priority_limit initial value, providing some tolerance
+to clients trying to open several streams at the connection start, yet
+low tolerance to flooding attempts.
+
+diff -r 3db945fda515 -r cdda286c0f1b src/http/v2/ngx_http_v2.c
+--- a/src/http/v2/ngx_http_v2.c	Fri Sep 22 19:23:57 2023 +0400
++++ b/src/http/v2/ngx_http_v2.c	Tue Oct 10 15:13:39 2023 +0300
+@@ -347,6 +347,7 @@
+     ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "http2 read handler");
+ 
+     h2c->blocked = 1;
++    h2c->new_streams = 0;
+ 
+     if (c->close) {
+         c->close = 0;
+@@ -1284,6 +1285,14 @@
+         goto rst_stream;
+     }
+ 
++    if (h2c->new_streams++ >= 2 * h2scf->concurrent_streams) {
++        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
++                      "client sent too many streams at once");
++
++        status = NGX_HTTP_V2_REFUSED_STREAM;
++        goto rst_stream;
++    }
++
+     if (!h2c->settings_ack
+         && !(h2c->state.flags & NGX_HTTP_V2_END_STREAM_FLAG)
+         && h2scf->preread_size < NGX_HTTP_V2_DEFAULT_WINDOW)
+@@ -1349,6 +1358,12 @@
+ 
+ rst_stream:
+ 
++    if (h2c->refused_streams++ > ngx_max(h2scf->concurrent_streams, 100)) {
++        ngx_log_error(NGX_LOG_INFO, h2c->connection->log, 0,
++                      "client sent too many refused streams");
++        return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_NO_ERROR);
++    }
++
+     if (ngx_http_v2_send_rst_stream(h2c, h2c->state.sid, status) != NGX_OK) {
+         return ngx_http_v2_connection_error(h2c, NGX_HTTP_V2_INTERNAL_ERROR);
+     }
+diff -r 3db945fda515 -r cdda286c0f1b src/http/v2/ngx_http_v2.h
+--- a/src/http/v2/ngx_http_v2.h	Fri Sep 22 19:23:57 2023 +0400
++++ b/src/http/v2/ngx_http_v2.h	Tue Oct 10 15:13:39 2023 +0300
+@@ -131,6 +131,8 @@
+     ngx_uint_t                       processing;
+     ngx_uint_t                       frames;
+     ngx_uint_t                       idle;
++    ngx_uint_t                       new_streams;
++    ngx_uint_t                       refused_streams;
+     ngx_uint_t                       priority_limit;
+ 
+     size_t                           send_window;
+

config/software/nginx.rb

@@ -42,6 +42,7 @@
 
 build do
   cwd = "#{Omnibus::Config.source_dir}/nginx"
+  patch source: 'CVE-2023-44487.patch'
 
   command ['./auto/configure',
            "--prefix=#{install_dir}/embedded",