SECURITY UPDATE: excessive memory allocation and out-of-bounds read in
ngx_http_scgi_module and ngx_http_uwsgi_module status line parsing
debian/patches/CVE-2026-42946.patch: save u->buffer.pos into
r->header_name_start before parsing the status line and restore it on
the NGX_ERROR fallback in ngx_http_scgi_process_status_line() and
ngx_http_uwsgi_process_status_line(), then reset r->state to 0 so an
unrecognised upstream status line no longer leaves the parser in a
stale state that can over-read worker process memory or crash the
worker; the same backtracking is also applied to ngx_http_proxy_module