[PATCH] HTTP/3: fixed NGX_HTTP_V3_VARLEN_INT_LEN value

[Maxim Dounin]

# HG changeset patch
# User Maxim Dounin <mdounin at mdounin.ru>
# Date 1781172660 -10800
#      Thu Jun 11 13:11:00 2026 +0300
# Node ID ba68cb5eeb1a46c189a1baef5f4b3b083a2f77e0
# Parent  9647f416bbae2c122d3a68976914b7228a8cf15f
HTTP/3: fixed NGX_HTTP_V3_VARLEN_INT_LEN value.

This change was missed in 8349:b13176e717ba, and in theory might cause
1-byte buffer overwrite in ngx_http_v3_body_filter() if memory buffers
larger than 1G are used (which is unlikely in practice).

See also:
https://github.com/freenginx/nginx/issues/21
https://github.com/nginx/nginx/commit/0f9f43b79eed64ab1a876be76ff0f49d499784fc

diff --git a/src/http/v3/ngx_http_v3.h b/src/http/v3/ngx_http_v3.h
--- a/src/http/v3/ngx_http_v3.h
+++ b/src/http/v3/ngx_http_v3.h
@@ -23,7 +23,7 @@
 #define NGX_HTTP_V3_HQ_ALPN_PROTO                  "\x0Ahq-interop"
 #define NGX_HTTP_V3_HQ_PROTO                       "hq-interop"
 
-#define NGX_HTTP_V3_VARLEN_INT_LEN                 4
+#define NGX_HTTP_V3_VARLEN_INT_LEN                 8
 #define NGX_HTTP_V3_PREFIX_INT_LEN                 11
 
 #define NGX_HTTP_V3_STREAM_CONTROL                 0x00