From 8f71770f095bfcab5a4caf8c7c15655e8bae2231 Mon Sep 17 00:00:00 2001
From: Vadim Zhestikov <v.zhestikov@f5.com>
Date: Tue, 11 Aug 2026 11:08:57 -0700
Subject: [PATCH] Tests: memcached response length overflow detection

A length that overflows when the size of the response trailer is added
to it is rejected, instead of being sent to the client as a content
length.

Marked TODO, as the fix is not yet released.
---
 memcached_fake_length.t | 96 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)
 create mode 100644 memcached_fake_length.t

diff --git a/memcached_fake_length.t b/memcached_fake_length.t
new file mode 100644
index 00000000..97753c0f
--- /dev/null
+++ b/memcached_fake_length.t
@@ -0,0 +1,96 @@
+#!/usr/bin/perl
+
+# (C) Nginx, Inc.
+
+# Test for memcached backend returning a length that overflows.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+use Socket qw/ CRLF /;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+my $t = Test::Nginx->new()->has(qw/http rewrite memcached/)->plan(1)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        location / {
+            set $memcached_key $uri;
+            memcached_pass 127.0.0.1:8081;
+        }
+    }
+}
+
+EOF
+
+$t->run_daemon(\&memcached_fake_daemon);
+$t->run();
+
+$t->waitforsocket('127.0.0.1:' . port(8081))
+	or die "Can't start fake memcached";
+
+###############################################################################
+
+# a length that overflows when the size of the trailer is added to it
+# is rejected, and is not sent to the client as a content length
+
+TODO: {
+local $TODO = 'not yet';
+
+like(http_get('/'), qr/502 Bad/, 'memcached invalid length');
+
+}
+
+###############################################################################
+
+sub memcached_fake_daemon {
+	my $server = IO::Socket::INET->new(
+		Proto => 'tcp',
+		LocalAddr => '127.0.0.1:' . port(8081),
+		Listen => 5,
+		Reuse => 1
+	)
+		or die "Can't create listening socket: $!\n";
+
+	local $SIG{PIPE} = 'IGNORE';
+
+	while (my $client = $server->accept()) {
+		$client->autoflush(1);
+
+		while (<$client>) {
+			last if (/\x0d\x0a$/);
+		}
+
+		print $client 'VALUE / 0 9223372036854775807' . CRLF;
+		print $client 'SEE-THIS' . CRLF . 'END' . CRLF;
+
+		close $client;
+	}
+}
+
+###############################################################################