It depends on the rod’s length, power, and action. If the bass rod is over 8 feet tall, with a medium-to-heavy power and fast action, then yes, you can use a bass rod for catching salmon and steelhead.
The problem here is that bass rods aren’t usually as powerful as the alternative because bass aren’t heavy fighters. You can certainly give it a go, but make sure it has the same qualifications as salmon steelhead rods.