Smashing the stack

Question 1

buffer

Answer 1

contiguous block of computer memory that holds multileinstance of the same data type

Question 2

arrays

Answer 2

variable in c

can be declared either static or dynamic

Question 3

static variables

Answer 3

allocated at load time on the data segment

Question 4

dynamic

Answer 4

dynamic variables are allocated at run time on the stack

Question 5

to overflow

Answer 5

to flow/fill over the top, brims or bounds

Question 6

stack-based buffer overflows

Answer 6

overflow of dynamic buffers

Question 7

three regions to organize a process in memory

Answer 7

text, data, and stack

Question 8

text region

Answer 8

fixed by the program and includes code (instructions) and read-only data
corresponds to the text section of the executable file
normally marked read-only
attempts to write to it will result in a segmentation violation

Question 9

data region

Answer 9

contains initialized and uninitialized data
stores static variables
corresponds to data-bss section of executable file
its size can be changed with the brk(2) system call
if xpansion of the bss data or the user stack exhausts available memory, proces is blocked and reschedule to runagain with larger memory space

Question 10

new memory is added…

Answer 10

between the data and stack segments

Question 11

what is “a stack”

Answer 11

abstract data type

Question 12

stack of objects property

Answer 12

las object placed on the stack will be the first obect removed– last in, first out queue- LIFO

Question 13

PUSH operation

Answer 13

adds an element at the top of the stack

Question 14

POP operation

Answer 14

reduces the stack size by one by removing the last element at the top of the stack

Question 15

a procedure call…

Answer 15

alters the flow of control like a jump
unline a jump, when finished performing its task, a function returns control to the statement or instruction following the call

Question 16

what does the stack do?

Answer 16

used to dynamically allocated the loca variables used in functions
to pass parameters to the functions
to return values from the function

Question 17

The stack region

Answer 17

a contiguous block of memory containing data.

Question 18

SP- stack pointer

Answer 18

a register that points to the top of the stack

Question 19

bottom of the stack

Answer 19

at a fixed address

Question 20

size of the stack

Answer 20

its size is dynamically adjusted by the kernel at run time

Question 21

what PUSHes and POPs

Answer 21

the CPU implements instruction to PUSH onto and POP off of the stack

Question 22

what does the stack consist of?

Answer 22

logical stack frames that are pushed when calling a function and popped when returning

Question 23

what is a stack frame?

Answer 23

a stack frame contains the parameters to a function, its local varaibles,a dn teh data necessary to recover the previous stack frame, including the value of the instruction poiner at the time of the function call

Question 24

how does the stack grow on many computers including INtel, motorola, sparc, and MIPS processors?

Answer 24

stack grows down towards lower memory addresses

Question 25

stack pointer can either point to

Answer 25

a) the last address on the stack

b) or the next free available address after the stack

Question 26

stack pointer (sP)

Answer 26

points to the top of the stack (lowest numericaladress)

Question 27

frame pointer (fp)

Answer 27

points to a fixed location within a frame

also known as local base pointer,