Proxy: fixed possible uninitialized memory access. The ngx_http_proxy_rewrite_cookie() function expects the value of the "Set-Cookie" header to be null-terminated, and for headers obtained from proxied server it is usually true. Now the ngx_http_proxy_rewrite() function preserves the null character while rewriting headers. This fixes accessing memory outside of rewritten value if both the "proxy_cookie_path" and "proxy_cookie_domain" directives are used in the same location.