C++ (Cpp) PT_REGS_SET_SYSCALL_RETURNの例

コード例 #1

ファイル: syscall.c プロジェクト: AK101111/linux

void handle_syscall(struct uml_pt_regs *r)
{
	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
	int syscall;

	/* Initialize the syscall number and default return value. */
	UPT_SYSCALL_NR(r) = PT_SYSCALL_NR(r->gp);
	PT_REGS_SET_SYSCALL_RETURN(regs, -ENOSYS);

	if (syscall_trace_enter(regs))
		return;

	/* Do the seccomp check after ptrace; failures should be fast. */
	if (secure_computing(NULL) == -1)
		return;

	/* Update the syscall number after orig_ax has potentially been updated
	 * with ptrace.
	 */
	UPT_SYSCALL_NR(r) = PT_SYSCALL_NR(r->gp);
	syscall = UPT_SYSCALL_NR(r);

	if (syscall >= 0 && syscall <= __NR_syscall_max)
		PT_REGS_SET_SYSCALL_RETURN(regs,
				EXECUTE_SYSCALL(syscall, regs));

	syscall_trace_leave(regs);
}

コード例 #2

void handle_syscall(struct uml_pt_regs *r)
{
	struct pt_regs *regs = container_of(r, struct pt_regs, regs);
	long result;
	int syscall;

	syscall_trace_enter(regs);

	/*
	 * This should go in the declaration of syscall, but when I do that,
	 * strace -f -c bash -c 'ls ; ls' breaks, sometimes not tracing
	 * children at all, sometimes hanging when bash doesn't see the first
	 * ls exit.
	 * The assembly looks functionally the same to me.  This is
	 *     gcc version 4.0.1 20050727 (Red Hat 4.0.1-5)
	 * in case it's a compiler bug.
	 */
	syscall = UPT_SYSCALL_NR(r); //it's just (r)->syscall in ptrace.h
        
        //<> jj debug
        if (syscall == 2){ //open system call
          open_cnt++;
          //          printk("called open\n");
        }


	if ((syscall >= NR_SYSCALLS) || (syscall < 0))
		result = -ENOSYS;
	else result = EXECUTE_SYSCALL(syscall, regs);

	PT_REGS_SET_SYSCALL_RETURN(regs, result);

	syscall_trace_leave(regs);
}

コード例 #3

ファイル: signal_kern.c プロジェクト: 12019/hg556a_source

/*
 * OK, we're invoking a handler
 */	
static int handle_signal(struct pt_regs *regs, unsigned long signr, 
			 struct k_sigaction *ka, siginfo_t *info, 
			 sigset_t *oldset, int error)
{
        __sighandler_t handler;
	void (*restorer)(void);
	unsigned long sp;
	sigset_t save;
	int err, ret;

	ret = 0;
	switch(error){
	case -ERESTART_RESTARTBLOCK:
		current_thread_info()->restart_block.fn = 
			do_no_restart_syscall;
	case -ERESTARTNOHAND:
		ret = -EINTR;
		break;

	case -ERESTARTSYS:
		if (!(ka->sa.sa_flags & SA_RESTART)) {
			ret = -EINTR;
			break;
		}
		/* fallthrough */
	case -ERESTARTNOINTR:
		PT_REGS_RESTART_SYSCALL(regs);
		PT_REGS_ORIG_SYSCALL(regs) = PT_REGS_SYSCALL_NR(regs);

		/* This is because of the UM_SET_SYSCALL_RETURN and the fact
		 * that on i386 the system call number and return value are
		 * in the same register.  When the system call restarts, %eax
		 * had better have the system call number in it.  Since the
		 * return value doesn't matter (except that it shouldn't be
		 * -ERESTART*), we'll stick the system call number there.
		 */
		ret = PT_REGS_SYSCALL_NR(regs);
		break;
	}

	handler = ka->sa.sa_handler;
	save = *oldset;

	if (ka->sa.sa_flags & SA_ONESHOT)
		ka->sa.sa_handler = SIG_DFL;

	if (!(ka->sa.sa_flags & SA_NODEFER)) {
		spin_lock_irq(&current->sighand->siglock);
		sigorsets(&current->blocked, &current->blocked, 
			  &ka->sa.sa_mask);
		sigaddset(&current->blocked, signr);
		recalc_sigpending();
		spin_unlock_irq(&current->sighand->siglock);
	}

	sp = PT_REGS_SP(regs);

	if((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
		sp = current->sas_ss_sp + current->sas_ss_size;
	
	if(error != 0) PT_REGS_SET_SYSCALL_RETURN(regs, ret);

	if (ka->sa.sa_flags & SA_RESTORER) restorer = ka->sa.sa_restorer;
	else restorer = NULL;

	if(ka->sa.sa_flags & SA_SIGINFO)
		err = setup_signal_stack_si(sp, signr, (unsigned long) handler,
					    restorer, regs, info, &save);
	else
		err = setup_signal_stack_sc(sp, signr, (unsigned long) handler,
					    restorer, regs, &save);
	if(err) goto segv;

	return(0);
 segv:
	force_segv(signr);
	return(1);
}