Beispiel #1
0
/*
 * set process group (setpgid/old setpgrp)
 *
 * caller does setpgid(targpid, targpgid)
 *
 * pid must be caller or child of caller (ESRCH)
 * if a child
 *	pid must be in same session (EPERM)
 *	pid can't have done an exec (EACCES)
 * if pgid != pid
 * 	there must exist some pid in same session having pgid (EPERM)
 * pid must not be session leader (EPERM)
 */
int
sys_setpgid(struct setpgid_args *uap)
{
	struct proc *curp = curproc;
	struct proc *targp;		/* target process */
	struct pgrp *pgrp = NULL;	/* target pgrp */
	int error;

	if (uap->pgid < 0)
		return (EINVAL);

	if (uap->pid != 0 && uap->pid != curp->p_pid) {
		if ((targp = pfind(uap->pid)) == NULL || !inferior(targp)) {
			if (targp)
				PRELE(targp);
			error = ESRCH;
			targp = NULL;
			goto done;
		}
		lwkt_gettoken(&targp->p_token);
		/* targp now referenced and its token is held */

		if (targp->p_pgrp == NULL ||
		    targp->p_session != curp->p_session) {
			error = EPERM;
			goto done;
		}
		if (targp->p_flags & P_EXEC) {
			error = EACCES;
			goto done;
		}
	} else {
		targp = curp;
		PHOLD(targp);
		lwkt_gettoken(&targp->p_token);
	}
	if (SESS_LEADER(targp)) {
		error = EPERM;
		goto done;
	}
	if (uap->pgid == 0) {
		uap->pgid = targp->p_pid;
	} else if (uap->pgid != targp->p_pid) {
		if ((pgrp = pgfind(uap->pgid)) == NULL ||
	            pgrp->pg_session != curp->p_session) {
			error = EPERM;
			goto done;
		}
	}
	error = enterpgrp(targp, uap->pgid, 0);
done:
	if (pgrp)
		pgrel(pgrp);
	if (targp) {
		lwkt_reltoken(&targp->p_token);
		PRELE(targp);
	}
	return (error);
}
Beispiel #2
0
/* ARGSUSED */
int
sys_setpgid(struct proc *curp, void *v, register_t *retval)
{
	struct sys_setpgid_args /* {
		syscallarg(pid_t) pid;
		syscallarg(int) pgid;
	} */ *uap = v;
	struct process *curpr = curp->p_p;
	struct process *targpr;		/* target process */
	struct pgrp *pgrp, *newpgrp;	/* target pgrp */
	pid_t pid;
	int pgid, error;

	pid = SCARG(uap, pid);
	pgid = SCARG(uap, pgid);

	if (pgid < 0)
		return (EINVAL);

	newpgrp = pool_get(&pgrp_pool, PR_WAITOK);

	if (pid != 0 && pid != curpr->ps_pid) {
		if ((targpr = prfind(pid)) == 0 || !inferior(targpr, curpr)) {
			error = ESRCH;
			goto out;
		}
		if (targpr->ps_session != curpr->ps_session) {
			error = EPERM;
			goto out;
		}
		if (targpr->ps_flags & PS_EXEC) {
			error = EACCES;
			goto out;
		}
	} else
		targpr = curpr;
	if (SESS_LEADER(targpr)) {
		error = EPERM;
		goto out;
	}
	if (pgid == 0)
		pgid = targpr->ps_pid;
	else if (pgid != targpr->ps_pid)
		if ((pgrp = pgfind(pgid)) == 0 ||
		    pgrp->pg_session != curpr->ps_session) {
			error = EPERM;
			goto out;
		}
	return (enterpgrp(targpr, pgid, newpgrp, NULL));
out:
	pool_put(&pgrp_pool, newpgrp);
	return (error);
}
/*
 * Process debugging system call.
 */
int
sys_ptrace(struct proc *p, void *v, register_t *retval)
{
	struct sys_ptrace_args /* {
		syscallarg(int) req;
		syscallarg(pid_t) pid;
		syscallarg(caddr_t) addr;
		syscallarg(int) data;
	} */ *uap = v;
	struct proc *t;				/* target thread */
	struct process *tr;			/* target process */
	struct uio uio;
	struct iovec iov;
	struct ptrace_io_desc piod;
	struct ptrace_event pe;
	struct ptrace_thread_state pts;
	struct reg *regs;
#if defined (PT_SETFPREGS) || defined (PT_GETFPREGS)
	struct fpreg *fpregs;
#endif
#if defined (PT_SETXMMREGS) || defined (PT_GETXMMREGS)
	struct xmmregs *xmmregs;
#endif
#ifdef PT_WCOOKIE
	register_t wcookie;
#endif
	int error, write;
	int temp;
	int req = SCARG(uap, req);
	int s;

	/* "A foolish consistency..." XXX */
	switch (req) {
	case PT_TRACE_ME:
		t = p;
		break;

	/* calls that only operate on the PID */
	case PT_READ_I:
	case PT_READ_D:
	case PT_WRITE_I:
	case PT_WRITE_D:
	case PT_KILL:
	case PT_ATTACH:
	case PT_IO:
	case PT_SET_EVENT_MASK:
	case PT_GET_EVENT_MASK:
	case PT_GET_PROCESS_STATE:
	case PT_GET_THREAD_FIRST:
	case PT_GET_THREAD_NEXT:
	default:
		/* Find the process we're supposed to be operating on. */
		if ((t = pfind(SCARG(uap, pid))) == NULL)
			return (ESRCH);
		if (t->p_flag & P_THREAD)
			return (ESRCH);
		break;

	/* calls that accept a PID or a thread ID */
	case PT_CONTINUE:
	case PT_DETACH:
#ifdef PT_STEP
	case PT_STEP:
#endif
	case PT_GETREGS:
	case PT_SETREGS:
#ifdef PT_GETFPREGS
	case PT_GETFPREGS:
#endif
#ifdef PT_SETFPREGS
	case PT_SETFPREGS:
#endif
#ifdef PT_GETXMMREGS
	case PT_GETXMMREGS:
#endif
#ifdef PT_SETXMMREGS
	case PT_SETXMMREGS:
#endif
		if (SCARG(uap, pid) > THREAD_PID_OFFSET) {
			t = pfind(SCARG(uap, pid) - THREAD_PID_OFFSET);
			if (t == NULL)
				return (ESRCH);
		} else {
			if ((t = pfind(SCARG(uap, pid))) == NULL)
				return (ESRCH);
			if (t->p_flag & P_THREAD)
				return (ESRCH);
		}
		break;
	}
	tr = t->p_p;

	if ((tr->ps_flags & PS_INEXEC) != 0)
		return (EAGAIN);

	/* Make sure we can operate on it. */
	switch (req) {
	case  PT_TRACE_ME:
		/* Saying that you're being traced is always legal. */
		break;

	case  PT_ATTACH:
		/*
		 * You can't attach to a process if:
		 *	(1) it's the process that's doing the attaching,
		 */
		if (tr == p->p_p)
			return (EINVAL);

		/*
		 *	(2) it's a system process
		 */
		if (ISSET(tr->ps_flags, PS_SYSTEM))
			return (EPERM);

		/*
		 *	(3) it's already being traced, or
		 */
		if (ISSET(tr->ps_flags, PS_TRACED))
			return (EBUSY);

		/*
		 *	(4) it's not owned by you, or the last exec
		 *	    gave us setuid/setgid privs (unless
		 *	    you're root), or...
		 * 
		 *      [Note: once PS_SUGID or PS_SUGIDEXEC gets set in
		 *	execve(), they stay set until the process does
		 *	another execve().  Hence this prevents a setuid
		 *	process which revokes its special privileges using
		 *	setuid() from being traced.  This is good security.]
		 */
		if ((tr->ps_ucred->cr_ruid != p->p_ucred->cr_ruid ||
		    ISSET(tr->ps_flags, PS_SUGIDEXEC | PS_SUGID)) &&
		    (error = suser(p, 0)) != 0)
			return (error);

		/*
		 * 	(4.5) it's not a child of the tracing process.
		 */
		if (global_ptrace == 0 && !inferior(tr, p->p_p) &&
		    (error = suser(p, 0)) != 0)
			return (error);

		/*
		 *	(5) ...it's init, which controls the security level
		 *	    of the entire system, and the system was not
		 *          compiled with permanently insecure mode turned
		 *	    on.
		 */
		if ((tr->ps_pid == 1) && (securelevel > -1))
			return (EPERM);

		/*
		 *	(6) it's an ancestor of the current process and
		 *	    not init (because that would create a loop in
		 *	    the process graph).
		 */
		if (tr->ps_pid != 1 && inferior(p->p_p, tr))
			return (EINVAL);
		break;

	case  PT_READ_I:
	case  PT_READ_D:
	case  PT_WRITE_I:
	case  PT_WRITE_D:
	case  PT_IO:
	case  PT_CONTINUE:
	case  PT_KILL:
	case  PT_DETACH:
#ifdef PT_STEP
	case  PT_STEP:
#endif
	case  PT_SET_EVENT_MASK:
	case  PT_GET_EVENT_MASK:
	case  PT_GET_PROCESS_STATE:
	case  PT_GETREGS:
	case  PT_SETREGS:
#ifdef PT_GETFPREGS
	case  PT_GETFPREGS:
#endif
#ifdef PT_SETFPREGS
	case  PT_SETFPREGS:
#endif
#ifdef PT_GETXMMREGS
	case  PT_GETXMMREGS:
#endif
#ifdef PT_SETXMMREGS
	case  PT_SETXMMREGS:
#endif
#ifdef PT_WCOOKIE
	case  PT_WCOOKIE:
#endif
		/*
		 * You can't do what you want to the process if:
		 *	(1) It's not being traced at all,
		 */
		if (!ISSET(tr->ps_flags, PS_TRACED))
			return (EPERM);

		/*
		 *	(2) it's not being traced by _you_, or
		 */
		if (tr->ps_pptr != p->p_p)
			return (EBUSY);

		/*
		 *	(3) it's not currently stopped.
		 */
		if (t->p_stat != SSTOP || !ISSET(tr->ps_flags, PS_WAITED))
			return (EBUSY);
		break;

	case  PT_GET_THREAD_FIRST:
	case  PT_GET_THREAD_NEXT:
		/*
		 * You can't do what you want to the process if:
		 *	(1) It's not being traced at all,
		 */
		if (!ISSET(tr->ps_flags, PS_TRACED))
			return (EPERM);

		/*
		 *	(2) it's not being traced by _you_, or
		 */
		if (tr->ps_pptr != p->p_p)
			return (EBUSY);

		/*
		 * Do the work here because the request isn't actually
		 * associated with 't'
		 */
		if (SCARG(uap, data) != sizeof(pts))
			return (EINVAL);

		if (req == PT_GET_THREAD_NEXT) {
			error = copyin(SCARG(uap, addr), &pts, sizeof(pts));
			if (error)
				return (error);

			t = pfind(pts.pts_tid - THREAD_PID_OFFSET);
			if (t == NULL || ISSET(t->p_flag, P_WEXIT))
				return (ESRCH);
			if (t->p_p != tr)
				return (EINVAL);
			t = TAILQ_NEXT(t, p_thr_link);
		} else {
			t = TAILQ_FIRST(&tr->ps_threads);
		}

		if (t == NULL)
			pts.pts_tid = -1;
		else
			pts.pts_tid = t->p_pid + THREAD_PID_OFFSET;
		return (copyout(&pts, SCARG(uap, addr), sizeof(pts)));

	default:			/* It was not a legal request. */
		return (EINVAL);
	}

	/* Do single-step fixup if needed. */
	FIX_SSTEP(t);

	/* Now do the operation. */
	write = 0;
	*retval = 0;

	switch (req) {
	case  PT_TRACE_ME:
		/* Just set the trace flag. */
		atomic_setbits_int(&tr->ps_flags, PS_TRACED);
		tr->ps_oppid = tr->ps_pptr->ps_pid;
		if (tr->ps_ptstat == NULL)
			tr->ps_ptstat = malloc(sizeof(*tr->ps_ptstat),
			    M_SUBPROC, M_WAITOK);
		memset(tr->ps_ptstat, 0, sizeof(*tr->ps_ptstat));
		return (0);

	case  PT_WRITE_I:		/* XXX no separate I and D spaces */
	case  PT_WRITE_D:
		write = 1;
		temp = SCARG(uap, data);
	case  PT_READ_I:		/* XXX no separate I and D spaces */
	case  PT_READ_D:
		/* write = 0 done above. */
		iov.iov_base = (caddr_t)&temp;
		iov.iov_len = sizeof(int);
		uio.uio_iov = &iov;
		uio.uio_iovcnt = 1;
		uio.uio_offset = (off_t)(vaddr_t)SCARG(uap, addr);
		uio.uio_resid = sizeof(int);
		uio.uio_segflg = UIO_SYSSPACE;
		uio.uio_rw = write ? UIO_WRITE : UIO_READ;
		uio.uio_procp = p;
		error = process_domem(p, t, &uio, write ? PT_WRITE_I :
				PT_READ_I);
		if (write == 0)
			*retval = temp;
		return (error);
	case  PT_IO:
		error = copyin(SCARG(uap, addr), &piod, sizeof(piod));
		if (error)
			return (error);
		iov.iov_base = piod.piod_addr;
		iov.iov_len = piod.piod_len;
		uio.uio_iov = &iov;
		uio.uio_iovcnt = 1;
		uio.uio_offset = (off_t)(vaddr_t)piod.piod_offs;
		uio.uio_resid = piod.piod_len;
		uio.uio_segflg = UIO_USERSPACE;
		uio.uio_procp = p;
		switch (piod.piod_op) {
		case PIOD_READ_I:
			req = PT_READ_I;
			uio.uio_rw = UIO_READ;
			break;
		case PIOD_READ_D:
			req = PT_READ_D;
			uio.uio_rw = UIO_READ;
			break;
		case PIOD_WRITE_I:
			req = PT_WRITE_I;
			uio.uio_rw = UIO_WRITE;
			break;
		case PIOD_WRITE_D:
			req = PT_WRITE_D;
			uio.uio_rw = UIO_WRITE;
			break;
		case PIOD_READ_AUXV:
			req = PT_READ_D;
			uio.uio_rw = UIO_READ;
			temp = tr->ps_emul->e_arglen * sizeof(char *);
			if (uio.uio_offset > temp)
				return (EIO);
			if (uio.uio_resid > temp - uio.uio_offset)
				uio.uio_resid = temp - uio.uio_offset;
			piod.piod_len = iov.iov_len = uio.uio_resid;
			error = process_auxv_offset(p, t, &uio);
			if (error)
				return (error);
			break;
		default:
			return (EINVAL);
		}
		error = process_domem(p, t, &uio, req);
		piod.piod_len -= uio.uio_resid;
		(void) copyout(&piod, SCARG(uap, addr), sizeof(piod));
		return (error);
#ifdef PT_STEP
	case  PT_STEP:
		/*
		 * From the 4.4BSD PRM:
		 * "Execution continues as in request PT_CONTINUE; however
		 * as soon as possible after execution of at least one
		 * instruction, execution stops again. [ ... ]"
		 */
#endif
	case  PT_CONTINUE:
		/*
		 * From the 4.4BSD PRM:
		 * "The data argument is taken as a signal number and the
		 * child's execution continues at location addr as if it
		 * incurred that signal.  Normally the signal number will
		 * be either 0 to indicate that the signal that caused the
		 * stop should be ignored, or that value fetched out of
		 * the process's image indicating which signal caused
		 * the stop.  If addr is (int *)1 then execution continues
		 * from where it stopped."
		 */

		if (SCARG(uap, pid) < THREAD_PID_OFFSET && tr->ps_single)
			t = tr->ps_single;

		/* Check that the data is a valid signal number or zero. */
		if (SCARG(uap, data) < 0 || SCARG(uap, data) >= NSIG)
			return (EINVAL);

		/* If the address parameter is not (int *)1, set the pc. */
		if ((int *)SCARG(uap, addr) != (int *)1)
			if ((error = process_set_pc(t, SCARG(uap, addr))) != 0)
				goto relebad;

#ifdef PT_STEP
		/*
		 * Arrange for a single-step, if that's requested and possible.
		 */
		error = process_sstep(t, req == PT_STEP);
		if (error)
			goto relebad;
#endif
		goto sendsig;

	case  PT_DETACH:
		/*
		 * From the 4.4BSD PRM:
		 * "The data argument is taken as a signal number and the
		 * child's execution continues at location addr as if it
		 * incurred that signal.  Normally the signal number will
		 * be either 0 to indicate that the signal that caused the
		 * stop should be ignored, or that value fetched out of
		 * the process's image indicating which signal caused
		 * the stop.  If addr is (int *)1 then execution continues
		 * from where it stopped."
		 */

		if (SCARG(uap, pid) < THREAD_PID_OFFSET && tr->ps_single)
			t = tr->ps_single;

		/* Check that the data is a valid signal number or zero. */
		if (SCARG(uap, data) < 0 || SCARG(uap, data) >= NSIG)
			return (EINVAL);

#ifdef PT_STEP
		/*
		 * Arrange for a single-step, if that's requested and possible.
		 */
		error = process_sstep(t, req == PT_STEP);
		if (error)
			goto relebad;
#endif

		/* give process back to original parent or init */
		if (tr->ps_oppid != tr->ps_pptr->ps_pid) {
			struct process *ppr;

			ppr = prfind(tr->ps_oppid);
			proc_reparent(tr, ppr ? ppr : initprocess);
		}

		/* not being traced any more */
		tr->ps_oppid = 0;
		atomic_clearbits_int(&tr->ps_flags, PS_TRACED|PS_WAITED);

	sendsig:
		memset(tr->ps_ptstat, 0, sizeof(*tr->ps_ptstat));

		/* Finally, deliver the requested signal (or none). */
		if (t->p_stat == SSTOP) {
			t->p_xstat = SCARG(uap, data);
			SCHED_LOCK(s);
			setrunnable(t);
			SCHED_UNLOCK(s);
		} else {
			if (SCARG(uap, data) != 0)
				psignal(t, SCARG(uap, data));
		}

		return (0);

	relebad:
		return (error);

	case  PT_KILL:
		if (SCARG(uap, pid) < THREAD_PID_OFFSET && tr->ps_single)
			t = tr->ps_single;

		/* just send the process a KILL signal. */
		SCARG(uap, data) = SIGKILL;
		goto sendsig;	/* in PT_CONTINUE, above. */

	case  PT_ATTACH:
		/*
		 * As was done in procfs:
		 * Go ahead and set the trace flag.
		 * Save the old parent (it's reset in
		 *   _DETACH, and also in kern_exit.c:wait4()
		 * Reparent the process so that the tracing
		 *   proc gets to see all the action.
		 * Stop the target.
		 */
		atomic_setbits_int(&tr->ps_flags, PS_TRACED);
		tr->ps_oppid = tr->ps_pptr->ps_pid;
		if (tr->ps_pptr != p->p_p)
			proc_reparent(tr, p->p_p);
		if (tr->ps_ptstat == NULL)
			tr->ps_ptstat = malloc(sizeof(*tr->ps_ptstat),
			    M_SUBPROC, M_WAITOK);
		SCARG(uap, data) = SIGSTOP;
		goto sendsig;

	case  PT_GET_EVENT_MASK:
		if (SCARG(uap, data) != sizeof(pe))
			return (EINVAL);
		memset(&pe, 0, sizeof(pe));
		pe.pe_set_event = tr->ps_ptmask;
		return (copyout(&pe, SCARG(uap, addr), sizeof(pe)));
	case  PT_SET_EVENT_MASK:
		if (SCARG(uap, data) != sizeof(pe))
			return (EINVAL);
		if ((error = copyin(SCARG(uap, addr), &pe, sizeof(pe))))
			return (error);
		tr->ps_ptmask = pe.pe_set_event;
		return (0);

	case  PT_GET_PROCESS_STATE:
		if (SCARG(uap, data) != sizeof(*tr->ps_ptstat))
			return (EINVAL);

		if (tr->ps_single)
			tr->ps_ptstat->pe_tid =
			    tr->ps_single->p_pid + THREAD_PID_OFFSET;

		return (copyout(tr->ps_ptstat, SCARG(uap, addr),
		    sizeof(*tr->ps_ptstat)));

	case  PT_SETREGS:
		KASSERT((p->p_flag & P_SYSTEM) == 0);
		if ((error = process_checkioperm(p, tr)) != 0)
			return (error);

		regs = malloc(sizeof(*regs), M_TEMP, M_WAITOK);
		error = copyin(SCARG(uap, addr), regs, sizeof(*regs));
		if (error == 0) {
			error = process_write_regs(t, regs);
		}
		free(regs, M_TEMP, sizeof(*regs));
		return (error);
	case  PT_GETREGS:
		KASSERT((p->p_flag & P_SYSTEM) == 0);
		if ((error = process_checkioperm(p, tr)) != 0)
			return (error);

		regs = malloc(sizeof(*regs), M_TEMP, M_WAITOK);
		error = process_read_regs(t, regs);
		if (error == 0)
			error = copyout(regs,
			    SCARG(uap, addr), sizeof (*regs));
		free(regs, M_TEMP, sizeof(*regs));
		return (error);
#ifdef PT_SETFPREGS
	case  PT_SETFPREGS:
		KASSERT((p->p_flag & P_SYSTEM) == 0);
		if ((error = process_checkioperm(p, tr)) != 0)
			return (error);

		fpregs = malloc(sizeof(*fpregs), M_TEMP, M_WAITOK);
		error = copyin(SCARG(uap, addr), fpregs, sizeof(*fpregs));
		if (error == 0) {
			error = process_write_fpregs(t, fpregs);
		}
		free(fpregs, M_TEMP, sizeof(*fpregs));
		return (error);
#endif
#ifdef PT_GETFPREGS
	case  PT_GETFPREGS:
		KASSERT((p->p_flag & P_SYSTEM) == 0);
		if ((error = process_checkioperm(p, tr)) != 0)
			return (error);

		fpregs = malloc(sizeof(*fpregs), M_TEMP, M_WAITOK);
		error = process_read_fpregs(t, fpregs);
		if (error == 0)
			error = copyout(fpregs,
			    SCARG(uap, addr), sizeof(*fpregs));
		free(fpregs, M_TEMP, sizeof(*fpregs));
		return (error);
#endif
#ifdef PT_SETXMMREGS
	case  PT_SETXMMREGS:
		KASSERT((p->p_flag & P_SYSTEM) == 0);
		if ((error = process_checkioperm(p, tr)) != 0)
			return (error);

		xmmregs = malloc(sizeof(*xmmregs), M_TEMP, M_WAITOK);
		error = copyin(SCARG(uap, addr), xmmregs, sizeof(*xmmregs));
		if (error == 0) {
			error = process_write_xmmregs(t, xmmregs);
		}
		free(xmmregs, M_TEMP, sizeof(*xmmregs));
		return (error);
#endif
#ifdef PT_GETXMMREGS
	case  PT_GETXMMREGS:
		KASSERT((p->p_flag & P_SYSTEM) == 0);
		if ((error = process_checkioperm(p, tr)) != 0)
			return (error);

		xmmregs = malloc(sizeof(*xmmregs), M_TEMP, M_WAITOK);
		error = process_read_xmmregs(t, xmmregs);
		if (error == 0)
			error = copyout(xmmregs,
			    SCARG(uap, addr), sizeof(*xmmregs));
		free(xmmregs, M_TEMP, sizeof(*xmmregs));
		return (error);
#endif
#ifdef PT_WCOOKIE
	case  PT_WCOOKIE:
		wcookie = process_get_wcookie (t);
		return (copyout(&wcookie, SCARG(uap, addr),
		    sizeof (register_t)));
#endif
	}

#ifdef DIAGNOSTIC
	panic("ptrace: impossible");
#endif
	return 0;
}