There is a serious error at syscall.c

[tonyhan18]

Hi! I'm a senior at Sognag University.
I'm trying to study OS by your project.

When I make code in my project referencing yours. There is a big problem in syscall.c.

void user_addr_check(const void *vaddr) function makes a big error when I run it. I think.... child process ended time is a little bit different... compare to the parent process. And it makes crashes.

So, I have changed this to below

case SYS_EXIT:
if(!is_user_vaddr(f->esp+4)) syscall_exit(-1);
//user_addr_check(f->esp+4);
syscall_exit((int)(f->esp+4));
break;

thank you for sharing. you are one of my best alumni.