Get absolute path of the executable in the Linux kernel, context of do_exec() kprobe/SystemTap

get_exe_name.c

static char* get_exe_name(int pid, char *buffer, int buffer_size)
{
    char *result = NULL;

	struct mm_struct* mm = current->mm;
	if (mm)
	{
		int lock_result = down_read_trylock(&mm->mmap_sem);
		if ((lock_result) && (mm->exe_file)) 
		{
			result = d_path(&mm->exe_file->f_path, buffer, buffer_size);            
			up_read(&mm->mmap_sem);
		}
	} 

    if (IS_ERR(result) == true)
    {
        return NULL;
    }
    
    return result;
}