SECURITY UPDATE: heap buffer overflow in ngx_http_map_uri_to_path() when
$request_filename is evaluated after a rewrite inside an "alias" location
debian/patches/CVE-2026-15176.patch: reject the URI to path mapping for
an "alias" location while r->uri_changed is set, and clear
r->valid_location in ngx_http_script_break_code() when the URI was
changed, so a rewritten URI shorter than the location prefix is no
longer mapped to a path