This will also be the fastest bet (if your requirements allow you to), as only a pointer is assigned, and no memory is copied from one place to another. Clang, GCC, and related compilers implement stack smashing protection (SSP) using StackGuard.
#STACK SMASHING DETECTED C FREE#
Note that in this last case, the string will be placed in a segment of your program that will not be modifiable, and that you cannot free that pointer either. That will create a pointer variable pointing to the constant string "Hello, world". Then again, if you don't plan on changing the contents and just want a way to refer to the string you can use: At any rate, it will not be much more efficient than using strcpy (only added cost of the function call). The compiler will create an array of appropriate size (13: 12 chars + terminating 0). Note that you are not providing a size for the array. Now, if you are just initializing and with a literal, you can just write: Those two reasons would force you to use strcpy (or better strncpy). You might need to change the contents of the string after initialization, or you might not be using a literal for initialization but rather another zero terminated string. I don't understand the reason you need to do strcpy. You could just print the address after initializing message="Hello, world.". Is there a reason for you to use strcpy(). Three such systems are Libsafe, and the StackGuard and ProPolice gcc patches.
![stack smashing detected c stack smashing detected c](https://image.slidesharecdn.com/main-130110034013-phpapp01/95/smashing-the-stack-33-638.jpg)
If it has been altered, the program exits with a segmentation fault. Stack-smashing protection is used to detect the most common buffer overflows by checking that the stack has not been altered when a function returns. The reason it doesn't report the error until the end is that the compiler has included a stack integrity check on the return of your main() function, which is flagging up the overflows at the end of your program. Shouldn't it have given me the error when I tried to do the strcpy?Ĭ doesn't perform array bounds checking, so if you write more data to the array than is allocated, it will put that data in it regardless. How come it worked for the first tow cases. I guess that arises when there's problems with boundaries in strings.īut that does raise another interesting equation.
![stack smashing detected c stack smashing detected c](https://user.oc-static.com/upload/2018/07/24/15324482583327_terminal.png)
That seems to have solved the stack smashing problem.