I recently upgraded some Symfony packages through composer and did basic upgrade commands (setup:upgrade, setup:di:compile, setup:static-content:deploy, cache:clean). Suddenly, my product pages come up blank. Every other page works fine. The system.log shows
main.CRITICAL: TypeError: Argument 2 passed to Magento\Catalog\Block\Product\ImageFactory::getLabel() must be of the type string, null given, called in /var/www/html/vendor/magento/module-catalog/Block/Product/ImageFactory.php on line 171 and defined in /var/www/html/vendor/magento/module-catalog/Block/Product/ImageFactory.php:117
When I view the source code of a product page, it shows something like this
<meta property="og:type" content="product" /><meta property="og:title" content="2011 Nitro Z6  - Hull Only" /><meta property="og:image" content="An error has happened during application run. See exception log for details.
I am using a custom theme, and it does have a view.xml file. I've tried disabling modules that effect the frontend, with no change.
Has anyone had this issue, or do you have any idea on what I can do to fix this?