Copy a function in memory and execute it
- by Elinghton
Hi everybody,
I would like to know how in C in can copy the content of a function into memroy and the execute it?
I'm trying to do something like this:
typedef void(*FUN)(int *);
char * myNewFunc;
char *allocExecutablePages (int pages)
{
template = (char *) valloc (getpagesize () * pages);
if (mprotect (template, getpagesize (),
PROT_READ|PROT_EXEC|PROT_WRITE) == -1) {
perror ("mprotect");
}
}
void f1 (int *v) {
*v = 10;
}
// allocate enough spcae but how much ??
myNewFunc = allocExecutablePages(...)
/* Copy f1 somewere else
* (how? assume that i know the size of f1 having done a (nm -S foo.o))
*/
((FUN)template)(&val);
printf("%i",val);
Thanks for your answers