What I called a misaligned buffer here is a buffer that doesn't start at the address that its type alignment advertises. For example if a type is aligned at 8, you'd expect it's address to be a multiple of 8. If it isn't, it's misaligned. In the test, I build a buffer that has some arbitrary alignment, then break it to make it start at an incorrect address before calling your function.
What I called a misaligned buffer here is a buffer that doesn't start at the address that its type alignment advertises. For example if a type is aligned at 8, you'd expect it's address to be a multiple of 8. If it isn't, it's misaligned. In the test, I build a buffer that has some arbitrary alignment, then break it to make it start at an incorrect address before calling your function.