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vt_ioctl.c
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1 /*
2  * Copyright (C) 1992 obz under the linux copyright
3  *
4  * Dynamic diacritical handling - [email protected] - Dec 1993
5  * Dynamic keymap and string allocation - [email protected] - May 1994
6  * Restrict VT switching via ioctl() - [email protected] - Dec 1995
7  * Some code moved for less code duplication - Andi Kleen - Mar 1997
8  * Check put/get_user, cleanups - [email protected] - Jun 2001
9  */
10 
11 #include <linux/types.h>
12 #include <linux/errno.h>
13 #include <linux/sched.h>
14 #include <linux/tty.h>
15 #include <linux/timer.h>
16 #include <linux/kernel.h>
17 #include <linux/compat.h>
18 #include <linux/module.h>
19 #include <linux/kd.h>
20 #include <linux/vt.h>
21 #include <linux/string.h>
22 #include <linux/slab.h>
23 #include <linux/major.h>
24 #include <linux/fs.h>
25 #include <linux/console.h>
26 #include <linux/consolemap.h>
27 #include <linux/signal.h>
28 #include <linux/timex.h>
29 
30 #include <asm/io.h>
31 #include <asm/uaccess.h>
32 
33 #include <linux/kbd_kern.h>
34 #include <linux/vt_kern.h>
35 #include <linux/kbd_diacr.h>
36 #include <linux/selection.h>
37 
39 extern struct tty_driver *console_driver;
40 
41 #define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
42 #define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
43 
44 /*
45  * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
46  * experimentation and study of X386 SYSV handling.
47  *
48  * One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
49  * /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
50  * and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
51  * always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
52  * ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
53  * /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
54  * to the current console is done by the main ioctl code.
55  */
56 
57 #ifdef CONFIG_X86
58 #include <linux/syscalls.h>
59 #endif
60 
61 static void complete_change_console(struct vc_data *vc);
62 
63 /*
64  * User space VT_EVENT handlers
65  */
66 
67 struct vt_event_wait {
68  struct list_head list;
69  struct vt_event event;
70  int done;
71 };
72 
73 static LIST_HEAD(vt_events);
74 static DEFINE_SPINLOCK(vt_event_lock);
75 static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue);
76 
86 void vt_event_post(unsigned int event, unsigned int old, unsigned int new)
87 {
88  struct list_head *pos, *head;
89  unsigned long flags;
90  int wake = 0;
91 
92  spin_lock_irqsave(&vt_event_lock, flags);
93  head = &vt_events;
94 
95  list_for_each(pos, head) {
96  struct vt_event_wait *ve = list_entry(pos,
97  struct vt_event_wait, list);
98  if (!(ve->event.event & event))
99  continue;
100  ve->event.event = event;
101  /* kernel view is consoles 0..n-1, user space view is
102  console 1..n with 0 meaning current, so we must bias */
103  ve->event.oldev = old + 1;
104  ve->event.newev = new + 1;
105  wake = 1;
106  ve->done = 1;
107  }
108  spin_unlock_irqrestore(&vt_event_lock, flags);
109  if (wake)
110  wake_up_interruptible(&vt_event_waitqueue);
111 }
112 
113 static void __vt_event_queue(struct vt_event_wait *vw)
114 {
115  unsigned long flags;
116  /* Prepare the event */
117  INIT_LIST_HEAD(&vw->list);
118  vw->done = 0;
119  /* Queue our event */
120  spin_lock_irqsave(&vt_event_lock, flags);
121  list_add(&vw->list, &vt_events);
122  spin_unlock_irqrestore(&vt_event_lock, flags);
123 }
124 
125 static void __vt_event_wait(struct vt_event_wait *vw)
126 {
127  /* Wait for it to pass */
128  wait_event_interruptible(vt_event_waitqueue, vw->done);
129 }
130 
131 static void __vt_event_dequeue(struct vt_event_wait *vw)
132 {
133  unsigned long flags;
134 
135  /* Dequeue it */
136  spin_lock_irqsave(&vt_event_lock, flags);
137  list_del(&vw->list);
138  spin_unlock_irqrestore(&vt_event_lock, flags);
139 }
140 
150 static void vt_event_wait(struct vt_event_wait *vw)
151 {
152  __vt_event_queue(vw);
153  __vt_event_wait(vw);
154  __vt_event_dequeue(vw);
155 }
156 
164 static int vt_event_wait_ioctl(struct vt_event __user *event)
165 {
166  struct vt_event_wait vw;
167 
168  if (copy_from_user(&vw.event, event, sizeof(struct vt_event)))
169  return -EFAULT;
170  /* Highest supported event for now */
171  if (vw.event.event & ~VT_MAX_EVENT)
172  return -EINVAL;
173 
174  vt_event_wait(&vw);
175  /* If it occurred report it */
176  if (vw.done) {
177  if (copy_to_user(event, &vw.event, sizeof(struct vt_event)))
178  return -EFAULT;
179  return 0;
180  }
181  return -EINTR;
182 }
183 
193 int vt_waitactive(int n)
194 {
195  struct vt_event_wait vw;
196  do {
197  vw.event.event = VT_EVENT_SWITCH;
198  __vt_event_queue(&vw);
199  if (n == fg_console + 1) {
200  __vt_event_dequeue(&vw);
201  break;
202  }
203  __vt_event_wait(&vw);
204  __vt_event_dequeue(&vw);
205  if (vw.done == 0)
206  return -EINTR;
207  } while (vw.event.newev != n);
208  return 0;
209 }
210 
211 /*
212  * these are the valid i/o ports we're allowed to change. they map all the
213  * video ports
214  */
215 #define GPFIRST 0x3b4
216 #define GPLAST 0x3df
217 #define GPNUM (GPLAST - GPFIRST + 1)
218 
219 
220 
221 static inline int
222 do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
223 {
224  struct consolefontdesc cfdarg;
225  int i;
226 
227  if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
228  return -EFAULT;
229 
230  switch (cmd) {
231  case PIO_FONTX:
232  if (!perm)
233  return -EPERM;
234  op->op = KD_FONT_OP_SET;
235  op->flags = KD_FONT_FLAG_OLD;
236  op->width = 8;
237  op->height = cfdarg.charheight;
238  op->charcount = cfdarg.charcount;
239  op->data = cfdarg.chardata;
240  return con_font_op(vc_cons[fg_console].d, op);
241  case GIO_FONTX: {
242  op->op = KD_FONT_OP_GET;
243  op->flags = KD_FONT_FLAG_OLD;
244  op->width = 8;
245  op->height = cfdarg.charheight;
246  op->charcount = cfdarg.charcount;
247  op->data = cfdarg.chardata;
248  i = con_font_op(vc_cons[fg_console].d, op);
249  if (i)
250  return i;
251  cfdarg.charheight = op->height;
252  cfdarg.charcount = op->charcount;
253  if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
254  return -EFAULT;
255  return 0;
256  }
257  }
258  return -EINVAL;
259 }
260 
261 static inline int
262 do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
263 {
264  struct unimapdesc tmp;
265 
266  if (copy_from_user(&tmp, user_ud, sizeof tmp))
267  return -EFAULT;
268  if (tmp.entries)
269  if (!access_ok(VERIFY_WRITE, tmp.entries,
270  tmp.entry_ct*sizeof(struct unipair)))
271  return -EFAULT;
272  switch (cmd) {
273  case PIO_UNIMAP:
274  if (!perm)
275  return -EPERM;
276  return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
277  case GIO_UNIMAP:
278  if (!perm && fg_console != vc->vc_num)
279  return -EPERM;
280  return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries);
281  }
282  return 0;
283 }
284 
285 
286 
287 /*
288  * We handle the console-specific ioctl's here. We allow the
289  * capability to modify any console, not just the fg_console.
290  */
291 int vt_ioctl(struct tty_struct *tty,
292  unsigned int cmd, unsigned long arg)
293 {
294  struct vc_data *vc = tty->driver_data;
295  struct console_font_op op; /* used in multiple places here */
296  unsigned int console;
297  unsigned char ucval;
298  unsigned int uival;
299  void __user *up = (void __user *)arg;
300  int i, perm;
301  int ret = 0;
302 
303  console = vc->vc_num;
304 
305 
306  if (!vc_cons_allocated(console)) { /* impossible? */
307  ret = -ENOIOCTLCMD;
308  goto out;
309  }
310 
311 
312  /*
313  * To have permissions to do most of the vt ioctls, we either have
314  * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
315  */
316  perm = 0;
317  if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
318  perm = 1;
319 
320  switch (cmd) {
321  case TIOCLINUX:
322  ret = tioclinux(tty, arg);
323  break;
324  case KIOCSOUND:
325  if (!perm)
326  return -EPERM;
327  /*
328  * The use of PIT_TICK_RATE is historic, it used to be
329  * the platform-dependent CLOCK_TICK_RATE between 2.6.12
330  * and 2.6.36, which was a minor but unfortunate ABI
331  * change. kd_mksound is locked by the input layer.
332  */
333  if (arg)
334  arg = PIT_TICK_RATE / arg;
335  kd_mksound(arg, 0);
336  break;
337 
338  case KDMKTONE:
339  if (!perm)
340  return -EPERM;
341  {
342  unsigned int ticks, count;
343 
344  /*
345  * Generate the tone for the appropriate number of ticks.
346  * If the time is zero, turn off sound ourselves.
347  */
348  ticks = HZ * ((arg >> 16) & 0xffff) / 1000;
349  count = ticks ? (arg & 0xffff) : 0;
350  if (count)
351  count = PIT_TICK_RATE / count;
352  kd_mksound(count, ticks);
353  break;
354  }
355 
356  case KDGKBTYPE:
357  /*
358  * this is na├»ve.
359  */
360  ucval = KB_101;
361  ret = put_user(ucval, (char __user *)arg);
362  break;
363 
364  /*
365  * These cannot be implemented on any machine that implements
366  * ioperm() in user level (such as Alpha PCs) or not at all.
367  *
368  * XXX: you should never use these, just call ioperm directly..
369  */
370 #ifdef CONFIG_X86
371  case KDADDIO:
372  case KDDELIO:
373  /*
374  * KDADDIO and KDDELIO may be able to add ports beyond what
375  * we reject here, but to be safe...
376  *
377  * These are locked internally via sys_ioperm
378  */
379  if (arg < GPFIRST || arg > GPLAST) {
380  ret = -EINVAL;
381  break;
382  }
383  ret = sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
384  break;
385 
386  case KDENABIO:
387  case KDDISABIO:
388  ret = sys_ioperm(GPFIRST, GPNUM,
389  (cmd == KDENABIO)) ? -ENXIO : 0;
390  break;
391 #endif
392 
393  /* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
394 
395  case KDKBDREP:
396  {
397  struct kbd_repeat kbrep;
398 
400  return -EPERM;
401 
402  if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
403  ret = -EFAULT;
404  break;
405  }
406  ret = kbd_rate(&kbrep);
407  if (ret)
408  break;
409  if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
410  ret = -EFAULT;
411  break;
412  }
413 
414  case KDSETMODE:
415  /*
416  * currently, setting the mode from KD_TEXT to KD_GRAPHICS
417  * doesn't do a whole lot. i'm not sure if it should do any
418  * restoration of modes or what...
419  *
420  * XXX It should at least call into the driver, fbdev's definitely
421  * need to restore their engine state. --BenH
422  */
423  if (!perm)
424  return -EPERM;
425  switch (arg) {
426  case KD_GRAPHICS:
427  break;
428  case KD_TEXT0:
429  case KD_TEXT1:
430  arg = KD_TEXT;
431  case KD_TEXT:
432  break;
433  default:
434  ret = -EINVAL;
435  goto out;
436  }
437  /* FIXME: this needs the console lock extending */
438  if (vc->vc_mode == (unsigned char) arg)
439  break;
440  vc->vc_mode = (unsigned char) arg;
441  if (console != fg_console)
442  break;
443  /*
444  * explicitly blank/unblank the screen if switching modes
445  */
446  console_lock();
447  if (arg == KD_TEXT)
449  else
450  do_blank_screen(1);
451  console_unlock();
452  break;
453 
454  case KDGETMODE:
455  uival = vc->vc_mode;
456  goto setint;
457 
458  case KDMAPDISP:
459  case KDUNMAPDISP:
460  /*
461  * these work like a combination of mmap and KDENABIO.
462  * this could be easily finished.
463  */
464  ret = -EINVAL;
465  break;
466 
467  case KDSKBMODE:
468  if (!perm)
469  return -EPERM;
470  ret = vt_do_kdskbmode(console, arg);
471  if (ret == 0)
472  tty_ldisc_flush(tty);
473  break;
474 
475  case KDGKBMODE:
476  uival = vt_do_kdgkbmode(console);
477  ret = put_user(uival, (int __user *)arg);
478  break;
479 
480  /* this could be folded into KDSKBMODE, but for compatibility
481  reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
482  case KDSKBMETA:
483  ret = vt_do_kdskbmeta(console, arg);
484  break;
485 
486  case KDGKBMETA:
487  /* FIXME: should review whether this is worth locking */
488  uival = vt_do_kdgkbmeta(console);
489  setint:
490  ret = put_user(uival, (int __user *)arg);
491  break;
492 
493  case KDGETKEYCODE:
494  case KDSETKEYCODE:
496  perm = 0;
497  ret = vt_do_kbkeycode_ioctl(cmd, up, perm);
498  break;
499 
500  case KDGKBENT:
501  case KDSKBENT:
502  ret = vt_do_kdsk_ioctl(cmd, up, perm, console);
503  break;
504 
505  case KDGKBSENT:
506  case KDSKBSENT:
507  ret = vt_do_kdgkb_ioctl(cmd, up, perm);
508  break;
509 
510  /* Diacritical processing. Handled in keyboard.c as it has
511  to operate on the keyboard locks and structures */
512  case KDGKBDIACR:
513  case KDGKBDIACRUC:
514  case KDSKBDIACR:
515  case KDSKBDIACRUC:
516  ret = vt_do_diacrit(cmd, up, perm);
517  break;
518 
519  /* the ioctls below read/set the flags usually shown in the leds */
520  /* don't use them - they will go away without warning */
521  case KDGKBLED:
522  case KDSKBLED:
523  case KDGETLED:
524  case KDSETLED:
525  ret = vt_do_kdskled(console, cmd, arg, perm);
526  break;
527 
528  /*
529  * A process can indicate its willingness to accept signals
530  * generated by pressing an appropriate key combination.
531  * Thus, one can have a daemon that e.g. spawns a new console
532  * upon a keypress and then changes to it.
533  * See also the kbrequest field of inittab(5).
534  */
535  case KDSIGACCEPT:
536  {
537  if (!perm || !capable(CAP_KILL))
538  return -EPERM;
539  if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
540  ret = -EINVAL;
541  else {
542  spin_lock_irq(&vt_spawn_con.lock);
543  put_pid(vt_spawn_con.pid);
544  vt_spawn_con.pid = get_pid(task_pid(current));
545  vt_spawn_con.sig = arg;
546  spin_unlock_irq(&vt_spawn_con.lock);
547  }
548  break;
549  }
550 
551  case VT_SETMODE:
552  {
553  struct vt_mode tmp;
554 
555  if (!perm)
556  return -EPERM;
557  if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
558  ret = -EFAULT;
559  goto out;
560  }
561  if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
562  ret = -EINVAL;
563  goto out;
564  }
565  console_lock();
566  vc->vt_mode = tmp;
567  /* the frsig is ignored, so we set it to 0 */
568  vc->vt_mode.frsig = 0;
569  put_pid(vc->vt_pid);
570  vc->vt_pid = get_pid(task_pid(current));
571  /* no switch is required -- [email protected] */
572  vc->vt_newvt = -1;
573  console_unlock();
574  break;
575  }
576 
577  case VT_GETMODE:
578  {
579  struct vt_mode tmp;
580  int rc;
581 
582  console_lock();
583  memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
584  console_unlock();
585 
586  rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
587  if (rc)
588  ret = -EFAULT;
589  break;
590  }
591 
592  /*
593  * Returns global vt state. Note that VT 0 is always open, since
594  * it's an alias for the current VT, and people can't use it here.
595  * We cannot return state for more than 16 VTs, since v_state is short.
596  */
597  case VT_GETSTATE:
598  {
599  struct vt_stat __user *vtstat = up;
600  unsigned short state, mask;
601 
602  /* Review: FIXME: Console lock ? */
603  if (put_user(fg_console + 1, &vtstat->v_active))
604  ret = -EFAULT;
605  else {
606  state = 1; /* /dev/tty0 is always open */
607  for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
608  ++i, mask <<= 1)
609  if (VT_IS_IN_USE(i))
610  state |= mask;
611  ret = put_user(state, &vtstat->v_state);
612  }
613  break;
614  }
615 
616  /*
617  * Returns the first available (non-opened) console.
618  */
619  case VT_OPENQRY:
620  /* FIXME: locking ? - but then this is a stupid API */
621  for (i = 0; i < MAX_NR_CONSOLES; ++i)
622  if (! VT_IS_IN_USE(i))
623  break;
624  uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
625  goto setint;
626 
627  /*
628  * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
629  * with num >= 1 (switches to vt 0, our console, are not allowed, just
630  * to preserve sanity).
631  */
632  case VT_ACTIVATE:
633  if (!perm)
634  return -EPERM;
635  if (arg == 0 || arg > MAX_NR_CONSOLES)
636  ret = -ENXIO;
637  else {
638  arg--;
639  console_lock();
640  ret = vc_allocate(arg);
641  console_unlock();
642  if (ret)
643  break;
644  set_console(arg);
645  }
646  break;
647 
648  case VT_SETACTIVATE:
649  {
650  struct vt_setactivate vsa;
651 
652  if (!perm)
653  return -EPERM;
654 
655  if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
656  sizeof(struct vt_setactivate))) {
657  ret = -EFAULT;
658  goto out;
659  }
660  if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
661  ret = -ENXIO;
662  else {
663  vsa.console--;
664  console_lock();
665  ret = vc_allocate(vsa.console);
666  if (ret == 0) {
667  struct vc_data *nvc;
668  /* This is safe providing we don't drop the
669  console sem between vc_allocate and
670  finishing referencing nvc */
671  nvc = vc_cons[vsa.console].d;
672  nvc->vt_mode = vsa.mode;
673  nvc->vt_mode.frsig = 0;
674  put_pid(nvc->vt_pid);
675  nvc->vt_pid = get_pid(task_pid(current));
676  }
677  console_unlock();
678  if (ret)
679  break;
680  /* Commence switch and lock */
681  /* Review set_console locks */
682  set_console(vsa.console);
683  }
684  break;
685  }
686 
687  /*
688  * wait until the specified VT has been activated
689  */
690  case VT_WAITACTIVE:
691  if (!perm)
692  return -EPERM;
693  if (arg == 0 || arg > MAX_NR_CONSOLES)
694  ret = -ENXIO;
695  else
696  ret = vt_waitactive(arg);
697  break;
698 
699  /*
700  * If a vt is under process control, the kernel will not switch to it
701  * immediately, but postpone the operation until the process calls this
702  * ioctl, allowing the switch to complete.
703  *
704  * According to the X sources this is the behavior:
705  * 0: pending switch-from not OK
706  * 1: pending switch-from OK
707  * 2: completed switch-to OK
708  */
709  case VT_RELDISP:
710  if (!perm)
711  return -EPERM;
712 
713  console_lock();
714  if (vc->vt_mode.mode != VT_PROCESS) {
715  console_unlock();
716  ret = -EINVAL;
717  break;
718  }
719  /*
720  * Switching-from response
721  */
722  if (vc->vt_newvt >= 0) {
723  if (arg == 0)
724  /*
725  * Switch disallowed, so forget we were trying
726  * to do it.
727  */
728  vc->vt_newvt = -1;
729 
730  else {
731  /*
732  * The current vt has been released, so
733  * complete the switch.
734  */
735  int newvt;
736  newvt = vc->vt_newvt;
737  vc->vt_newvt = -1;
738  ret = vc_allocate(newvt);
739  if (ret) {
740  console_unlock();
741  break;
742  }
743  /*
744  * When we actually do the console switch,
745  * make sure we are atomic with respect to
746  * other console switches..
747  */
748  complete_change_console(vc_cons[newvt].d);
749  }
750  } else {
751  /*
752  * Switched-to response
753  */
754  /*
755  * If it's just an ACK, ignore it
756  */
757  if (arg != VT_ACKACQ)
758  ret = -EINVAL;
759  }
760  console_unlock();
761  break;
762 
763  /*
764  * Disallocate memory associated to VT (but leave VT1)
765  */
766  case VT_DISALLOCATE:
767  if (arg > MAX_NR_CONSOLES) {
768  ret = -ENXIO;
769  break;
770  }
771  if (arg == 0) {
772  /* deallocate all unused consoles, but leave 0 */
773  console_lock();
774  for (i=1; i<MAX_NR_CONSOLES; i++)
775  if (! VT_BUSY(i))
776  vc_deallocate(i);
777  console_unlock();
778  } else {
779  /* deallocate a single console, if possible */
780  arg--;
781  if (VT_BUSY(arg))
782  ret = -EBUSY;
783  else if (arg) { /* leave 0 */
784  console_lock();
785  vc_deallocate(arg);
786  console_unlock();
787  }
788  }
789  break;
790 
791  case VT_RESIZE:
792  {
793  struct vt_sizes __user *vtsizes = up;
794  struct vc_data *vc;
795 
796  ushort ll,cc;
797  if (!perm)
798  return -EPERM;
799  if (get_user(ll, &vtsizes->v_rows) ||
800  get_user(cc, &vtsizes->v_cols))
801  ret = -EFAULT;
802  else {
803  console_lock();
804  for (i = 0; i < MAX_NR_CONSOLES; i++) {
805  vc = vc_cons[i].d;
806 
807  if (vc) {
808  vc->vc_resize_user = 1;
809  /* FIXME: review v tty lock */
810  vc_resize(vc_cons[i].d, cc, ll);
811  }
812  }
813  console_unlock();
814  }
815  break;
816  }
817 
818  case VT_RESIZEX:
819  {
820  struct vt_consize __user *vtconsize = up;
821  ushort ll,cc,vlin,clin,vcol,ccol;
822  if (!perm)
823  return -EPERM;
824  if (!access_ok(VERIFY_READ, vtconsize,
825  sizeof(struct vt_consize))) {
826  ret = -EFAULT;
827  break;
828  }
829  /* FIXME: Should check the copies properly */
830  __get_user(ll, &vtconsize->v_rows);
831  __get_user(cc, &vtconsize->v_cols);
832  __get_user(vlin, &vtconsize->v_vlin);
833  __get_user(clin, &vtconsize->v_clin);
834  __get_user(vcol, &vtconsize->v_vcol);
835  __get_user(ccol, &vtconsize->v_ccol);
836  vlin = vlin ? vlin : vc->vc_scan_lines;
837  if (clin) {
838  if (ll) {
839  if (ll != vlin/clin) {
840  /* Parameters don't add up */
841  ret = -EINVAL;
842  break;
843  }
844  } else
845  ll = vlin/clin;
846  }
847  if (vcol && ccol) {
848  if (cc) {
849  if (cc != vcol/ccol) {
850  ret = -EINVAL;
851  break;
852  }
853  } else
854  cc = vcol/ccol;
855  }
856 
857  if (clin > 32) {
858  ret = -EINVAL;
859  break;
860  }
861 
862  for (i = 0; i < MAX_NR_CONSOLES; i++) {
863  if (!vc_cons[i].d)
864  continue;
865  console_lock();
866  if (vlin)
867  vc_cons[i].d->vc_scan_lines = vlin;
868  if (clin)
869  vc_cons[i].d->vc_font.height = clin;
870  vc_cons[i].d->vc_resize_user = 1;
871  vc_resize(vc_cons[i].d, cc, ll);
872  console_unlock();
873  }
874  break;
875  }
876 
877  case PIO_FONT: {
878  if (!perm)
879  return -EPERM;
880  op.op = KD_FONT_OP_SET;
881  op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
882  op.width = 8;
883  op.height = 0;
884  op.charcount = 256;
885  op.data = up;
886  ret = con_font_op(vc_cons[fg_console].d, &op);
887  break;
888  }
889 
890  case GIO_FONT: {
891  op.op = KD_FONT_OP_GET;
892  op.flags = KD_FONT_FLAG_OLD;
893  op.width = 8;
894  op.height = 32;
895  op.charcount = 256;
896  op.data = up;
897  ret = con_font_op(vc_cons[fg_console].d, &op);
898  break;
899  }
900 
901  case PIO_CMAP:
902  if (!perm)
903  ret = -EPERM;
904  else
905  ret = con_set_cmap(up);
906  break;
907 
908  case GIO_CMAP:
909  ret = con_get_cmap(up);
910  break;
911 
912  case PIO_FONTX:
913  case GIO_FONTX:
914  ret = do_fontx_ioctl(cmd, up, perm, &op);
915  break;
916 
917  case PIO_FONTRESET:
918  {
919  if (!perm)
920  return -EPERM;
921 
922 #ifdef BROKEN_GRAPHICS_PROGRAMS
923  /* With BROKEN_GRAPHICS_PROGRAMS defined, the default
924  font is not saved. */
925  ret = -ENOSYS;
926  break;
927 #else
928  {
930  op.data = NULL;
931  ret = con_font_op(vc_cons[fg_console].d, &op);
932  if (ret)
933  break;
934  console_lock();
936  console_unlock();
937  break;
938  }
939 #endif
940  }
941 
942  case KDFONTOP: {
943  if (copy_from_user(&op, up, sizeof(op))) {
944  ret = -EFAULT;
945  break;
946  }
947  if (!perm && op.op != KD_FONT_OP_GET)
948  return -EPERM;
949  ret = con_font_op(vc, &op);
950  if (ret)
951  break;
952  if (copy_to_user(up, &op, sizeof(op)))
953  ret = -EFAULT;
954  break;
955  }
956 
957  case PIO_SCRNMAP:
958  if (!perm)
959  ret = -EPERM;
960  else
961  ret = con_set_trans_old(up);
962  break;
963 
964  case GIO_SCRNMAP:
965  ret = con_get_trans_old(up);
966  break;
967 
968  case PIO_UNISCRNMAP:
969  if (!perm)
970  ret = -EPERM;
971  else
972  ret = con_set_trans_new(up);
973  break;
974 
975  case GIO_UNISCRNMAP:
976  ret = con_get_trans_new(up);
977  break;
978 
979  case PIO_UNIMAPCLR:
980  { struct unimapinit ui;
981  if (!perm)
982  return -EPERM;
983  ret = copy_from_user(&ui, up, sizeof(struct unimapinit));
984  if (ret)
985  ret = -EFAULT;
986  else
987  con_clear_unimap(vc, &ui);
988  break;
989  }
990 
991  case PIO_UNIMAP:
992  case GIO_UNIMAP:
993  ret = do_unimap_ioctl(cmd, up, perm, vc);
994  break;
995 
996  case VT_LOCKSWITCH:
998  return -EPERM;
999  vt_dont_switch = 1;
1000  break;
1001  case VT_UNLOCKSWITCH:
1003  return -EPERM;
1004  vt_dont_switch = 0;
1005  break;
1006  case VT_GETHIFONTMASK:
1007  ret = put_user(vc->vc_hi_font_mask,
1008  (unsigned short __user *)arg);
1009  break;
1010  case VT_WAITEVENT:
1011  ret = vt_event_wait_ioctl((struct vt_event __user *)arg);
1012  break;
1013  default:
1014  ret = -ENOIOCTLCMD;
1015  }
1016 out:
1017  return ret;
1018 }
1019 
1020 void reset_vc(struct vc_data *vc)
1021 {
1022  vc->vc_mode = KD_TEXT;
1023  vt_reset_unicode(vc->vc_num);
1024  vc->vt_mode.mode = VT_AUTO;
1025  vc->vt_mode.waitv = 0;
1026  vc->vt_mode.relsig = 0;
1027  vc->vt_mode.acqsig = 0;
1028  vc->vt_mode.frsig = 0;
1029  put_pid(vc->vt_pid);
1030  vc->vt_pid = NULL;
1031  vc->vt_newvt = -1;
1032  if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
1033  reset_palette(vc);
1034 }
1035 
1036 void vc_SAK(struct work_struct *work)
1037 {
1038  struct vc *vc_con =
1039  container_of(work, struct vc, SAK_work);
1040  struct vc_data *vc;
1041  struct tty_struct *tty;
1042 
1043  console_lock();
1044  vc = vc_con->d;
1045  if (vc) {
1046  /* FIXME: review tty ref counting */
1047  tty = vc->port.tty;
1048  /*
1049  * SAK should also work in all raw modes and reset
1050  * them properly.
1051  */
1052  if (tty)
1053  __do_SAK(tty);
1054  reset_vc(vc);
1055  }
1056  console_unlock();
1057 }
1058 
1059 #ifdef CONFIG_COMPAT
1060 
1061 struct compat_consolefontdesc {
1062  unsigned short charcount; /* characters in font (256 or 512) */
1063  unsigned short charheight; /* scan lines per character (1-32) */
1064  compat_caddr_t chardata; /* font data in expanded form */
1065 };
1066 
1067 static inline int
1068 compat_fontx_ioctl(int cmd, struct compat_consolefontdesc __user *user_cfd,
1069  int perm, struct console_font_op *op)
1070 {
1071  struct compat_consolefontdesc cfdarg;
1072  int i;
1073 
1074  if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc)))
1075  return -EFAULT;
1076 
1077  switch (cmd) {
1078  case PIO_FONTX:
1079  if (!perm)
1080  return -EPERM;
1081  op->op = KD_FONT_OP_SET;
1082  op->flags = KD_FONT_FLAG_OLD;
1083  op->width = 8;
1084  op->height = cfdarg.charheight;
1085  op->charcount = cfdarg.charcount;
1086  op->data = compat_ptr(cfdarg.chardata);
1087  return con_font_op(vc_cons[fg_console].d, op);
1088  case GIO_FONTX:
1089  op->op = KD_FONT_OP_GET;
1090  op->flags = KD_FONT_FLAG_OLD;
1091  op->width = 8;
1092  op->height = cfdarg.charheight;
1093  op->charcount = cfdarg.charcount;
1094  op->data = compat_ptr(cfdarg.chardata);
1095  i = con_font_op(vc_cons[fg_console].d, op);
1096  if (i)
1097  return i;
1098  cfdarg.charheight = op->height;
1099  cfdarg.charcount = op->charcount;
1100  if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc)))
1101  return -EFAULT;
1102  return 0;
1103  }
1104  return -EINVAL;
1105 }
1106 
1107 struct compat_console_font_op {
1108  compat_uint_t op; /* operation code KD_FONT_OP_* */
1109  compat_uint_t flags; /* KD_FONT_FLAG_* */
1110  compat_uint_t width, height; /* font size */
1111  compat_uint_t charcount;
1112  compat_caddr_t data; /* font data with height fixed to 32 */
1113 };
1114 
1115 static inline int
1116 compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
1117  int perm, struct console_font_op *op, struct vc_data *vc)
1118 {
1119  int i;
1120 
1121  if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op)))
1122  return -EFAULT;
1123  if (!perm && op->op != KD_FONT_OP_GET)
1124  return -EPERM;
1125  op->data = compat_ptr(((struct compat_console_font_op *)op)->data);
1126  i = con_font_op(vc, op);
1127  if (i)
1128  return i;
1129  ((struct compat_console_font_op *)op)->data = (unsigned long)op->data;
1130  if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op)))
1131  return -EFAULT;
1132  return 0;
1133 }
1134 
1135 struct compat_unimapdesc {
1136  unsigned short entry_ct;
1138 };
1139 
1140 static inline int
1141 compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
1142  int perm, struct vc_data *vc)
1143 {
1144  struct compat_unimapdesc tmp;
1145  struct unipair __user *tmp_entries;
1146 
1147  if (copy_from_user(&tmp, user_ud, sizeof tmp))
1148  return -EFAULT;
1149  tmp_entries = compat_ptr(tmp.entries);
1150  if (tmp_entries)
1151  if (!access_ok(VERIFY_WRITE, tmp_entries,
1152  tmp.entry_ct*sizeof(struct unipair)))
1153  return -EFAULT;
1154  switch (cmd) {
1155  case PIO_UNIMAP:
1156  if (!perm)
1157  return -EPERM;
1158  return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
1159  case GIO_UNIMAP:
1160  if (!perm && fg_console != vc->vc_num)
1161  return -EPERM;
1162  return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
1163  }
1164  return 0;
1165 }
1166 
1167 long vt_compat_ioctl(struct tty_struct *tty,
1168  unsigned int cmd, unsigned long arg)
1169 {
1170  struct vc_data *vc = tty->driver_data;
1171  struct console_font_op op; /* used in multiple places here */
1172  unsigned int console;
1173  void __user *up = (void __user *)arg;
1174  int perm;
1175  int ret = 0;
1176 
1177  console = vc->vc_num;
1178 
1179  if (!vc_cons_allocated(console)) { /* impossible? */
1180  ret = -ENOIOCTLCMD;
1181  goto out;
1182  }
1183 
1184  /*
1185  * To have permissions to do most of the vt ioctls, we either have
1186  * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
1187  */
1188  perm = 0;
1189  if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
1190  perm = 1;
1191 
1192  switch (cmd) {
1193  /*
1194  * these need special handlers for incompatible data structures
1195  */
1196  case PIO_FONTX:
1197  case GIO_FONTX:
1198  ret = compat_fontx_ioctl(cmd, up, perm, &op);
1199  break;
1200 
1201  case KDFONTOP:
1202  ret = compat_kdfontop_ioctl(up, perm, &op, vc);
1203  break;
1204 
1205  case PIO_UNIMAP:
1206  case GIO_UNIMAP:
1207  ret = compat_unimap_ioctl(cmd, up, perm, vc);
1208  break;
1209 
1210  /*
1211  * all these treat 'arg' as an integer
1212  */
1213  case KIOCSOUND:
1214  case KDMKTONE:
1215 #ifdef CONFIG_X86
1216  case KDADDIO:
1217  case KDDELIO:
1218 #endif
1219  case KDSETMODE:
1220  case KDMAPDISP:
1221  case KDUNMAPDISP:
1222  case KDSKBMODE:
1223  case KDSKBMETA:
1224  case KDSKBLED:
1225  case KDSETLED:
1226  case KDSIGACCEPT:
1227  case VT_ACTIVATE:
1228  case VT_WAITACTIVE:
1229  case VT_RELDISP:
1230  case VT_DISALLOCATE:
1231  case VT_RESIZE:
1232  case VT_RESIZEX:
1233  goto fallback;
1234 
1235  /*
1236  * the rest has a compatible data structure behind arg,
1237  * but we have to convert it to a proper 64 bit pointer.
1238  */
1239  default:
1240  arg = (unsigned long)compat_ptr(arg);
1241  goto fallback;
1242  }
1243 out:
1244  return ret;
1245 
1246 fallback:
1247  return vt_ioctl(tty, cmd, arg);
1248 }
1249 
1250 
1251 #endif /* CONFIG_COMPAT */
1252 
1253 
1254 /*
1255  * Performs the back end of a vt switch. Called under the console
1256  * semaphore.
1257  */
1258 static void complete_change_console(struct vc_data *vc)
1259 {
1260  unsigned char old_vc_mode;
1261  int old = fg_console;
1262 
1264 
1265  /*
1266  * If we're switching, we could be going from KD_GRAPHICS to
1267  * KD_TEXT mode or vice versa, which means we need to blank or
1268  * unblank the screen later.
1269  */
1270  old_vc_mode = vc_cons[fg_console].d->vc_mode;
1271  switch_screen(vc);
1272 
1273  /*
1274  * This can't appear below a successful kill_pid(). If it did,
1275  * then the *blank_screen operation could occur while X, having
1276  * received acqsig, is waking up on another processor. This
1277  * condition can lead to overlapping accesses to the VGA range
1278  * and the framebuffer (causing system lockups).
1279  *
1280  * To account for this we duplicate this code below only if the
1281  * controlling process is gone and we've called reset_vc.
1282  */
1283  if (old_vc_mode != vc->vc_mode) {
1284  if (vc->vc_mode == KD_TEXT)
1285  do_unblank_screen(1);
1286  else
1287  do_blank_screen(1);
1288  }
1289 
1290  /*
1291  * If this new console is under process control, send it a signal
1292  * telling it that it has acquired. Also check if it has died and
1293  * clean up (similar to logic employed in change_console())
1294  */
1295  if (vc->vt_mode.mode == VT_PROCESS) {
1296  /*
1297  * Send the signal as privileged - kill_pid() will
1298  * tell us if the process has gone or something else
1299  * is awry
1300  */
1301  if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
1302  /*
1303  * The controlling process has died, so we revert back to
1304  * normal operation. In this case, we'll also change back
1305  * to KD_TEXT mode. I'm not sure if this is strictly correct
1306  * but it saves the agony when the X server dies and the screen
1307  * remains blanked due to KD_GRAPHICS! It would be nice to do
1308  * this outside of VT_PROCESS but there is no single process
1309  * to account for and tracking tty count may be undesirable.
1310  */
1311  reset_vc(vc);
1312 
1313  if (old_vc_mode != vc->vc_mode) {
1314  if (vc->vc_mode == KD_TEXT)
1315  do_unblank_screen(1);
1316  else
1317  do_blank_screen(1);
1318  }
1319  }
1320  }
1321 
1322  /*
1323  * Wake anyone waiting for their VT to activate
1324  */
1326  return;
1327 }
1328 
1329 /*
1330  * Performs the front-end of a vt switch
1331  */
1332 void change_console(struct vc_data *new_vc)
1333 {
1334  struct vc_data *vc;
1335 
1336  if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
1337  return;
1338 
1339  /*
1340  * If this vt is in process mode, then we need to handshake with
1341  * that process before switching. Essentially, we store where that
1342  * vt wants to switch to and wait for it to tell us when it's done
1343  * (via VT_RELDISP ioctl).
1344  *
1345  * We also check to see if the controlling process still exists.
1346  * If it doesn't, we reset this vt to auto mode and continue.
1347  * This is a cheap way to track process control. The worst thing
1348  * that can happen is: we send a signal to a process, it dies, and
1349  * the switch gets "lost" waiting for a response; hopefully, the
1350  * user will try again, we'll detect the process is gone (unless
1351  * the user waits just the right amount of time :-) and revert the
1352  * vt to auto control.
1353  */
1354  vc = vc_cons[fg_console].d;
1355  if (vc->vt_mode.mode == VT_PROCESS) {
1356  /*
1357  * Send the signal as privileged - kill_pid() will
1358  * tell us if the process has gone or something else
1359  * is awry.
1360  *
1361  * We need to set vt_newvt *before* sending the signal or we
1362  * have a race.
1363  */
1364  vc->vt_newvt = new_vc->vc_num;
1365  if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
1366  /*
1367  * It worked. Mark the vt to switch to and
1368  * return. The process needs to send us a
1369  * VT_RELDISP ioctl to complete the switch.
1370  */
1371  return;
1372  }
1373 
1374  /*
1375  * The controlling process has died, so we revert back to
1376  * normal operation. In this case, we'll also change back
1377  * to KD_TEXT mode. I'm not sure if this is strictly correct
1378  * but it saves the agony when the X server dies and the screen
1379  * remains blanked due to KD_GRAPHICS! It would be nice to do
1380  * this outside of VT_PROCESS but there is no single process
1381  * to account for and tracking tty count may be undesirable.
1382  */
1383  reset_vc(vc);
1384 
1385  /*
1386  * Fall through to normal (VT_AUTO) handling of the switch...
1387  */
1388  }
1389 
1390  /*
1391  * Ignore all switches in KD_GRAPHICS+VT_AUTO mode
1392  */
1393  if (vc->vc_mode == KD_GRAPHICS)
1394  return;
1395 
1396  complete_change_console(new_vc);
1397 }
1398 
1399 /* Perform a kernel triggered VT switch for suspend/resume */
1400 
1401 static int disable_vt_switch;
1402 
1403 int vt_move_to_console(unsigned int vt, int alloc)
1404 {
1405  int prev;
1406 
1407  console_lock();
1408  /* Graphics mode - up to X */
1409  if (disable_vt_switch) {
1410  console_unlock();
1411  return 0;
1412  }
1413  prev = fg_console;
1414 
1415  if (alloc && vc_allocate(vt)) {
1416  /* we can't have a free VC for now. Too bad,
1417  * we don't want to mess the screen for now. */
1418  console_unlock();
1419  return -ENOSPC;
1420  }
1421 
1422  if (set_console(vt)) {
1423  /*
1424  * We're unable to switch to the SUSPEND_CONSOLE.
1425  * Let the calling function know so it can decide
1426  * what to do.
1427  */
1428  console_unlock();
1429  return -EIO;
1430  }
1431  console_unlock();
1432  if (vt_waitactive(vt + 1)) {
1433  pr_debug("Suspend: Can't switch VCs.");
1434  return -EINTR;
1435  }
1436  return prev;
1437 }
1438 
1439 /*
1440  * Normally during a suspend, we allocate a new console and switch to it.
1441  * When we resume, we switch back to the original console. This switch
1442  * can be slow, so on systems where the framebuffer can handle restoration
1443  * of video registers anyways, there's little point in doing the console
1444  * switch. This function allows you to disable it by passing it '0'.
1445  */
1446 void pm_set_vt_switch(int do_switch)
1447 {
1448  console_lock();
1449  disable_vt_switch = !do_switch;
1450  console_unlock();
1451 }