I think the twitter thread I linked answers your questions?
"use after free" is an instance of a memory access pattern that is considered invalid from the program's point of view.
What happens depends on the situation:
Was the memory returned to the operating system? If so it will probably result in a page fault and if you don't have a thing to handle the signal then the OS will crash your program.
Was the memory part of an arena managed by the custom allocator that still owns it? If so it will return whatever value is contained in the address being dereferenced.
"use after free" is an instance of a memory access pattern that is considered invalid from the program's point of view.
What happens depends on the situation:
Was the memory returned to the operating system? If so it will probably result in a page fault and if you don't have a thing to handle the signal then the OS will crash your program.
Was the memory part of an arena managed by the custom allocator that still owns it? If so it will return whatever value is contained in the address being dereferenced.