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Lecture An toàn Hệ điều hành: Stack Overflows has contents: Buffers, reading past the end of a buffer, writing past the end of a buffer, stacks and functions, overflowing buffers on the stack, kiểm soát EIP.
Stack Overflows Buffers • A buffer is defined as a limited, contiguously allocated set of memory • Stack overflows are possible because no inherent bounds-checking exists onbuffers in the C or C++ languages reading past the end of a buffer #include #include int main () { int array[5] = {1, 2, 3, 4, 5}; printf(“%d\n”, array[5] ); } This example shows how easy it is to read past the end of a buffer; C provides no built-in protection writing past the end of a buffer int main () { int array[5]; int i; for (i = 0; i