Single linked list

Question

I have created a single linked list. Everything works fine.

I just want to know if I have done anything potentially dangerous in my code. The code snippets I am concern

Answer 1

Following normal naming convensions, push and pop are related to stacks - i.e. push() should add an item to the top of the stack (you add to the tail of the list, which is fine!), and pop() should return and remove the item from the top of the stack (you search for a named item anywhere in the list and remove it.)
Function names aside, I would suggest a more generic (abstract) implementation of the list, where the content of a node is a pointer to arbitrary data (which in your special case will later be a product_data). This way your linked list can be re-used for any content, and is easier to debug, read and to maintain.
It would also be a better idea not to have stuff global, but rather permit multiple instances of a list. The normal C way is to keep the data in a struct, and then to pass an instance as first argument to each function.