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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 1992 obz under the linux copyright
4 *
5 * Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
6 * Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
7 * Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
8 * Some code moved for less code duplication - Andi Kleen - Mar 1997
9 * Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
10 */
11
12#include <linux/types.h>
13#include <linux/errno.h>
14#include <linux/sched/signal.h>
15#include <linux/tty.h>
16#include <linux/timer.h>
17#include <linux/kernel.h>
18#include <linux/compat.h>
19#include <linux/module.h>
20#include <linux/kd.h>
21#include <linux/vt.h>
22#include <linux/string.h>
23#include <linux/slab.h>
24#include <linux/major.h>
25#include <linux/fs.h>
26#include <linux/console.h>
27#include <linux/consolemap.h>
28#include <linux/signal.h>
29#include <linux/suspend.h>
30#include <linux/timex.h>
31
32#include <asm/io.h>
33#include <linux/uaccess.h>
34
35#include <linux/nospec.h>
36
37#include <linux/kbd_kern.h>
38#include <linux/vt_kern.h>
39#include <linux/kbd_diacr.h>
40#include <linux/selection.h>
41
42char vt_dont_switch;
43extern struct tty_driver *console_driver;
44
45#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
46#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
47
48/*
49 * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
50 * experimentation and study of X386 SYSV handling.
51 *
52 * One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
53 * /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
54 * and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
55 * always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
56 * ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
57 * /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
58 * to the current console is done by the main ioctl code.
59 */
60
61#ifdef CONFIG_X86
62#include <asm/syscalls.h>
63#endif
64
65static void complete_change_console(struct vc_data *vc);
66
67/*
68 * User space VT_EVENT handlers
69 */
70
71struct vt_event_wait {
72 struct list_head list;
73 struct vt_event event;
74 int done;
75};
76
77static LIST_HEAD(vt_events);
78static DEFINE_SPINLOCK(vt_event_lock);
79static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue);
80
81/**
82 * vt_event_post
83 * @event: the event that occurred
84 * @old: old console
85 * @new: new console
86 *
87 * Post an VT event to interested VT handlers
88 */
89
90void vt_event_post(unsigned int event, unsigned int old, unsigned int new)
91{
92 struct list_head *pos, *head;
93 unsigned long flags;
94 int wake = 0;
95
96 spin_lock_irqsave(&vt_event_lock, flags);
97 head = &vt_events;
98
99 list_for_each(pos, head) {
100 struct vt_event_wait *ve = list_entry(pos,
101 struct vt_event_wait, list);
102 if (!(ve->event.event & event))
103 continue;
104 ve->event.event = event;
105 /* kernel view is consoles 0..n-1, user space view is
106 console 1..n with 0 meaning current, so we must bias */
107 ve->event.oldev = old + 1;
108 ve->event.newev = new + 1;
109 wake = 1;
110 ve->done = 1;
111 }
112 spin_unlock_irqrestore(&vt_event_lock, flags);
113 if (wake)
114 wake_up_interruptible(&vt_event_waitqueue);
115}
116
117static void __vt_event_queue(struct vt_event_wait *vw)
118{
119 unsigned long flags;
120 /* Prepare the event */
121 INIT_LIST_HEAD(&vw->list);
122 vw->done = 0;
123 /* Queue our event */
124 spin_lock_irqsave(&vt_event_lock, flags);
125 list_add(&vw->list, &vt_events);
126 spin_unlock_irqrestore(&vt_event_lock, flags);
127}
128
129static void __vt_event_wait(struct vt_event_wait *vw)
130{
131 /* Wait for it to pass */
132 wait_event_interruptible(vt_event_waitqueue, vw->done);
133}
134
135static void __vt_event_dequeue(struct vt_event_wait *vw)
136{
137 unsigned long flags;
138
139 /* Dequeue it */
140 spin_lock_irqsave(&vt_event_lock, flags);
141 list_del(&vw->list);
142 spin_unlock_irqrestore(&vt_event_lock, flags);
143}
144
145/**
146 * vt_event_wait - wait for an event
147 * @vw: our event
148 *
149 * Waits for an event to occur which completes our vt_event_wait
150 * structure. On return the structure has wv->done set to 1 for success
151 * or 0 if some event such as a signal ended the wait.
152 */
153
154static void vt_event_wait(struct vt_event_wait *vw)
155{
156 __vt_event_queue(vw);
157 __vt_event_wait(vw);
158 __vt_event_dequeue(vw);
159}
160
161/**
162 * vt_event_wait_ioctl - event ioctl handler
163 * @arg: argument to ioctl
164 *
165 * Implement the VT_WAITEVENT ioctl using the VT event interface
166 */
167
168static int vt_event_wait_ioctl(struct vt_event __user *event)
169{
170 struct vt_event_wait vw;
171
172 if (copy_from_user(&vw.event, event, sizeof(struct vt_event)))
173 return -EFAULT;
174 /* Highest supported event for now */
175 if (vw.event.event & ~VT_MAX_EVENT)
176 return -EINVAL;
177
178 vt_event_wait(&vw);
179 /* If it occurred report it */
180 if (vw.done) {
181 if (copy_to_user(event, &vw.event, sizeof(struct vt_event)))
182 return -EFAULT;
183 return 0;
184 }
185 return -EINTR;
186}
187
188/**
189 * vt_waitactive - active console wait
190 * @event: event code
191 * @n: new console
192 *
193 * Helper for event waits. Used to implement the legacy
194 * event waiting ioctls in terms of events
195 */
196
197int vt_waitactive(int n)
198{
199 struct vt_event_wait vw;
200 do {
201 vw.event.event = VT_EVENT_SWITCH;
202 __vt_event_queue(&vw);
203 if (n == fg_console + 1) {
204 __vt_event_dequeue(&vw);
205 break;
206 }
207 __vt_event_wait(&vw);
208 __vt_event_dequeue(&vw);
209 if (vw.done == 0)
210 return -EINTR;
211 } while (vw.event.newev != n);
212 return 0;
213}
214
215/*
216 * these are the valid i/o ports we're allowed to change. they map all the
217 * video ports
218 */
219#define GPFIRST 0x3b4
220#define GPLAST 0x3df
221#define GPNUM (GPLAST - GPFIRST + 1)
222
223
224
225static inline int
226do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
227{
228 struct consolefontdesc cfdarg;
229 int i;
230
231 if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
232 return -EFAULT;
233
234 switch (cmd) {
235 case PIO_FONTX:
236 if (!perm)
237 return -EPERM;
238 op->op = KD_FONT_OP_SET;
239 op->flags = KD_FONT_FLAG_OLD;
240 op->width = 8;
241 op->height = cfdarg.charheight;
242 op->charcount = cfdarg.charcount;
243 op->data = cfdarg.chardata;
244 return con_font_op(vc_cons[fg_console].d, op);
245 case GIO_FONTX: {
246 op->op = KD_FONT_OP_GET;
247 op->flags = KD_FONT_FLAG_OLD;
248 op->width = 8;
249 op->height = cfdarg.charheight;
250 op->charcount = cfdarg.charcount;
251 op->data = cfdarg.chardata;
252 i = con_font_op(vc_cons[fg_console].d, op);
253 if (i)
254 return i;
255 cfdarg.charheight = op->height;
256 cfdarg.charcount = op->charcount;
257 if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
258 return -EFAULT;
259 return 0;
260 }
261 }
262 return -EINVAL;
263}
264
265static inline int
266do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
267{
268 struct unimapdesc tmp;
269
270 if (copy_from_user(&tmp, user_ud, sizeof tmp))
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/* deallocate a single console, if possible (leave 0) */
286static int vt_disallocate(unsigned int vc_num)
287{
288 struct vc_data *vc = NULL;
289 int ret = 0;
290
291 console_lock();
292 if (VT_BUSY(vc_num))
293 ret = -EBUSY;
294 else if (vc_num)
295 vc = vc_deallocate(vc_num);
296 console_unlock();
297
298 if (vc && vc_num >= MIN_NR_CONSOLES) {
299 tty_port_destroy(&vc->port);
300 kfree(vc);
301 }
302
303 return ret;
304}
305
306/* deallocate all unused consoles, but leave 0 */
307static void vt_disallocate_all(void)
308{
309 struct vc_data *vc[MAX_NR_CONSOLES];
310 int i;
311
312 console_lock();
313 for (i = 1; i < MAX_NR_CONSOLES; i++)
314 if (!VT_BUSY(i))
315 vc[i] = vc_deallocate(i);
316 else
317 vc[i] = NULL;
318 console_unlock();
319
320 for (i = 1; i < MAX_NR_CONSOLES; i++) {
321 if (vc[i] && i >= MIN_NR_CONSOLES) {
322 tty_port_destroy(&vc[i]->port);
323 kfree(vc[i]);
324 }
325 }
326}
327
328
329/*
330 * We handle the console-specific ioctl's here. We allow the
331 * capability to modify any console, not just the fg_console.
332 */
333int vt_ioctl(struct tty_struct *tty,
334 unsigned int cmd, unsigned long arg)
335{
336 struct vc_data *vc = tty->driver_data;
337 struct console_font_op op; /* used in multiple places here */
338 unsigned int console;
339 unsigned char ucval;
340 unsigned int uival;
341 void __user *up = (void __user *)arg;
342 int i, perm;
343 int ret = 0;
344
345 console = vc->vc_num;
346
347
348 if (!vc_cons_allocated(console)) { /* impossible? */
349 ret = -ENOIOCTLCMD;
350 goto out;
351 }
352
353
354 /*
355 * To have permissions to do most of the vt ioctls, we either have
356 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
357 */
358 perm = 0;
359 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
360 perm = 1;
361
362 switch (cmd) {
363 case TIOCLINUX:
364 ret = tioclinux(tty, arg);
365 break;
366 case KIOCSOUND:
367 if (!perm)
368 return -EPERM;
369 /*
370 * The use of PIT_TICK_RATE is historic, it used to be
371 * the platform-dependent CLOCK_TICK_RATE between 2.6.12
372 * and 2.6.36, which was a minor but unfortunate ABI
373 * change. kd_mksound is locked by the input layer.
374 */
375 if (arg)
376 arg = PIT_TICK_RATE / arg;
377 kd_mksound(arg, 0);
378 break;
379
380 case KDMKTONE:
381 if (!perm)
382 return -EPERM;
383 {
384 unsigned int ticks, count;
385
386 /*
387 * Generate the tone for the appropriate number of ticks.
388 * If the time is zero, turn off sound ourselves.
389 */
390 ticks = msecs_to_jiffies((arg >> 16) & 0xffff);
391 count = ticks ? (arg & 0xffff) : 0;
392 if (count)
393 count = PIT_TICK_RATE / count;
394 kd_mksound(count, ticks);
395 break;
396 }
397
398 case KDGKBTYPE:
399 /*
400 * this is naïve.
401 */
402 ucval = KB_101;
403 ret = put_user(ucval, (char __user *)arg);
404 break;
405
406 /*
407 * These cannot be implemented on any machine that implements
408 * ioperm() in user level (such as Alpha PCs) or not at all.
409 *
410 * XXX: you should never use these, just call ioperm directly..
411 */
412#ifdef CONFIG_X86
413 case KDADDIO:
414 case KDDELIO:
415 /*
416 * KDADDIO and KDDELIO may be able to add ports beyond what
417 * we reject here, but to be safe...
418 *
419 * These are locked internally via sys_ioperm
420 */
421 if (arg < GPFIRST || arg > GPLAST) {
422 ret = -EINVAL;
423 break;
424 }
425 ret = ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
426 break;
427
428 case KDENABIO:
429 case KDDISABIO:
430 ret = ksys_ioperm(GPFIRST, GPNUM,
431 (cmd == KDENABIO)) ? -ENXIO : 0;
432 break;
433#endif
434
435 /* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
436
437 case KDKBDREP:
438 {
439 struct kbd_repeat kbrep;
440
441 if (!capable(CAP_SYS_TTY_CONFIG))
442 return -EPERM;
443
444 if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
445 ret = -EFAULT;
446 break;
447 }
448 ret = kbd_rate(&kbrep);
449 if (ret)
450 break;
451 if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
452 ret = -EFAULT;
453 break;
454 }
455
456 case KDSETMODE:
457 /*
458 * currently, setting the mode from KD_TEXT to KD_GRAPHICS
459 * doesn't do a whole lot. i'm not sure if it should do any
460 * restoration of modes or what...
461 *
462 * XXX It should at least call into the driver, fbdev's definitely
463 * need to restore their engine state. --BenH
464 */
465 if (!perm)
466 return -EPERM;
467 switch (arg) {
468 case KD_GRAPHICS:
469 break;
470 case KD_TEXT0:
471 case KD_TEXT1:
472 arg = KD_TEXT;
473 case KD_TEXT:
474 break;
475 default:
476 ret = -EINVAL;
477 goto out;
478 }
479 /* FIXME: this needs the console lock extending */
480 if (vc->vc_mode == (unsigned char) arg)
481 break;
482 vc->vc_mode = (unsigned char) arg;
483 if (console != fg_console)
484 break;
485 /*
486 * explicitly blank/unblank the screen if switching modes
487 */
488 console_lock();
489 if (arg == KD_TEXT)
490 do_unblank_screen(1);
491 else
492 do_blank_screen(1);
493 console_unlock();
494 break;
495
496 case KDGETMODE:
497 uival = vc->vc_mode;
498 goto setint;
499
500 case KDMAPDISP:
501 case KDUNMAPDISP:
502 /*
503 * these work like a combination of mmap and KDENABIO.
504 * this could be easily finished.
505 */
506 ret = -EINVAL;
507 break;
508
509 case KDSKBMODE:
510 if (!perm)
511 return -EPERM;
512 ret = vt_do_kdskbmode(console, arg);
513 if (ret == 0)
514 tty_ldisc_flush(tty);
515 break;
516
517 case KDGKBMODE:
518 uival = vt_do_kdgkbmode(console);
519 ret = put_user(uival, (int __user *)arg);
520 break;
521
522 /* this could be folded into KDSKBMODE, but for compatibility
523 reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
524 case KDSKBMETA:
525 ret = vt_do_kdskbmeta(console, arg);
526 break;
527
528 case KDGKBMETA:
529 /* FIXME: should review whether this is worth locking */
530 uival = vt_do_kdgkbmeta(console);
531 setint:
532 ret = put_user(uival, (int __user *)arg);
533 break;
534
535 case KDGETKEYCODE:
536 case KDSETKEYCODE:
537 if(!capable(CAP_SYS_TTY_CONFIG))
538 perm = 0;
539 ret = vt_do_kbkeycode_ioctl(cmd, up, perm);
540 break;
541
542 case KDGKBENT:
543 case KDSKBENT:
544 ret = vt_do_kdsk_ioctl(cmd, up, perm, console);
545 break;
546
547 case KDGKBSENT:
548 case KDSKBSENT:
549 ret = vt_do_kdgkb_ioctl(cmd, up, perm);
550 break;
551
552 /* Diacritical processing. Handled in keyboard.c as it has
553 to operate on the keyboard locks and structures */
554 case KDGKBDIACR:
555 case KDGKBDIACRUC:
556 case KDSKBDIACR:
557 case KDSKBDIACRUC:
558 ret = vt_do_diacrit(cmd, up, perm);
559 break;
560
561 /* the ioctls below read/set the flags usually shown in the leds */
562 /* don't use them - they will go away without warning */
563 case KDGKBLED:
564 case KDSKBLED:
565 case KDGETLED:
566 case KDSETLED:
567 ret = vt_do_kdskled(console, cmd, arg, perm);
568 break;
569
570 /*
571 * A process can indicate its willingness to accept signals
572 * generated by pressing an appropriate key combination.
573 * Thus, one can have a daemon that e.g. spawns a new console
574 * upon a keypress and then changes to it.
575 * See also the kbrequest field of inittab(5).
576 */
577 case KDSIGACCEPT:
578 {
579 if (!perm || !capable(CAP_KILL))
580 return -EPERM;
581 if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
582 ret = -EINVAL;
583 else {
584 spin_lock_irq(&vt_spawn_con.lock);
585 put_pid(vt_spawn_con.pid);
586 vt_spawn_con.pid = get_pid(task_pid(current));
587 vt_spawn_con.sig = arg;
588 spin_unlock_irq(&vt_spawn_con.lock);
589 }
590 break;
591 }
592
593 case VT_SETMODE:
594 {
595 struct vt_mode tmp;
596
597 if (!perm)
598 return -EPERM;
599 if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
600 ret = -EFAULT;
601 goto out;
602 }
603 if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
604 ret = -EINVAL;
605 goto out;
606 }
607 console_lock();
608 vc->vt_mode = tmp;
609 /* the frsig is ignored, so we set it to 0 */
610 vc->vt_mode.frsig = 0;
611 put_pid(vc->vt_pid);
612 vc->vt_pid = get_pid(task_pid(current));
613 /* no switch is required -- saw@shade.msu.ru */
614 vc->vt_newvt = -1;
615 console_unlock();
616 break;
617 }
618
619 case VT_GETMODE:
620 {
621 struct vt_mode tmp;
622 int rc;
623
624 console_lock();
625 memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
626 console_unlock();
627
628 rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
629 if (rc)
630 ret = -EFAULT;
631 break;
632 }
633
634 /*
635 * Returns global vt state. Note that VT 0 is always open, since
636 * it's an alias for the current VT, and people can't use it here.
637 * We cannot return state for more than 16 VTs, since v_state is short.
638 */
639 case VT_GETSTATE:
640 {
641 struct vt_stat __user *vtstat = up;
642 unsigned short state, mask;
643
644 /* Review: FIXME: Console lock ? */
645 if (put_user(fg_console + 1, &vtstat->v_active))
646 ret = -EFAULT;
647 else {
648 state = 1; /* /dev/tty0 is always open */
649 for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
650 ++i, mask <<= 1)
651 if (VT_IS_IN_USE(i))
652 state |= mask;
653 ret = put_user(state, &vtstat->v_state);
654 }
655 break;
656 }
657
658 /*
659 * Returns the first available (non-opened) console.
660 */
661 case VT_OPENQRY:
662 /* FIXME: locking ? - but then this is a stupid API */
663 for (i = 0; i < MAX_NR_CONSOLES; ++i)
664 if (! VT_IS_IN_USE(i))
665 break;
666 uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
667 goto setint;
668
669 /*
670 * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
671 * with num >= 1 (switches to vt 0, our console, are not allowed, just
672 * to preserve sanity).
673 */
674 case VT_ACTIVATE:
675 if (!perm)
676 return -EPERM;
677 if (arg == 0 || arg > MAX_NR_CONSOLES)
678 ret = -ENXIO;
679 else {
680 arg--;
681 console_lock();
682 ret = vc_allocate(arg);
683 console_unlock();
684 if (ret)
685 break;
686 set_console(arg);
687 }
688 break;
689
690 case VT_SETACTIVATE:
691 {
692 struct vt_setactivate vsa;
693
694 if (!perm)
695 return -EPERM;
696
697 if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
698 sizeof(struct vt_setactivate))) {
699 ret = -EFAULT;
700 goto out;
701 }
702 if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
703 ret = -ENXIO;
704 else {
705 vsa.console = array_index_nospec(vsa.console,
706 MAX_NR_CONSOLES + 1);
707 vsa.console--;
708 console_lock();
709 ret = vc_allocate(vsa.console);
710 if (ret == 0) {
711 struct vc_data *nvc;
712 /* This is safe providing we don't drop the
713 console sem between vc_allocate and
714 finishing referencing nvc */
715 nvc = vc_cons[vsa.console].d;
716 nvc->vt_mode = vsa.mode;
717 nvc->vt_mode.frsig = 0;
718 put_pid(nvc->vt_pid);
719 nvc->vt_pid = get_pid(task_pid(current));
720 }
721 console_unlock();
722 if (ret)
723 break;
724 /* Commence switch and lock */
725 /* Review set_console locks */
726 set_console(vsa.console);
727 }
728 break;
729 }
730
731 /*
732 * wait until the specified VT has been activated
733 */
734 case VT_WAITACTIVE:
735 if (!perm)
736 return -EPERM;
737 if (arg == 0 || arg > MAX_NR_CONSOLES)
738 ret = -ENXIO;
739 else
740 ret = vt_waitactive(arg);
741 break;
742
743 /*
744 * If a vt is under process control, the kernel will not switch to it
745 * immediately, but postpone the operation until the process calls this
746 * ioctl, allowing the switch to complete.
747 *
748 * According to the X sources this is the behavior:
749 * 0: pending switch-from not OK
750 * 1: pending switch-from OK
751 * 2: completed switch-to OK
752 */
753 case VT_RELDISP:
754 if (!perm)
755 return -EPERM;
756
757 console_lock();
758 if (vc->vt_mode.mode != VT_PROCESS) {
759 console_unlock();
760 ret = -EINVAL;
761 break;
762 }
763 /*
764 * Switching-from response
765 */
766 if (vc->vt_newvt >= 0) {
767 if (arg == 0)
768 /*
769 * Switch disallowed, so forget we were trying
770 * to do it.
771 */
772 vc->vt_newvt = -1;
773
774 else {
775 /*
776 * The current vt has been released, so
777 * complete the switch.
778 */
779 int newvt;
780 newvt = vc->vt_newvt;
781 vc->vt_newvt = -1;
782 ret = vc_allocate(newvt);
783 if (ret) {
784 console_unlock();
785 break;
786 }
787 /*
788 * When we actually do the console switch,
789 * make sure we are atomic with respect to
790 * other console switches..
791 */
792 complete_change_console(vc_cons[newvt].d);
793 }
794 } else {
795 /*
796 * Switched-to response
797 */
798 /*
799 * If it's just an ACK, ignore it
800 */
801 if (arg != VT_ACKACQ)
802 ret = -EINVAL;
803 }
804 console_unlock();
805 break;
806
807 /*
808 * Disallocate memory associated to VT (but leave VT1)
809 */
810 case VT_DISALLOCATE:
811 if (arg > MAX_NR_CONSOLES) {
812 ret = -ENXIO;
813 break;
814 }
815 if (arg == 0)
816 vt_disallocate_all();
817 else
818 ret = vt_disallocate(--arg);
819 break;
820
821 case VT_RESIZE:
822 {
823 struct vt_sizes __user *vtsizes = up;
824 struct vc_data *vc;
825
826 ushort ll,cc;
827 if (!perm)
828 return -EPERM;
829 if (get_user(ll, &vtsizes->v_rows) ||
830 get_user(cc, &vtsizes->v_cols))
831 ret = -EFAULT;
832 else {
833 console_lock();
834 for (i = 0; i < MAX_NR_CONSOLES; i++) {
835 vc = vc_cons[i].d;
836
837 if (vc) {
838 vc->vc_resize_user = 1;
839 /* FIXME: review v tty lock */
840 vc_resize(vc_cons[i].d, cc, ll);
841 }
842 }
843 console_unlock();
844 }
845 break;
846 }
847
848 case VT_RESIZEX:
849 {
850 struct vt_consize v;
851 if (!perm)
852 return -EPERM;
853 if (copy_from_user(&v, up, sizeof(struct vt_consize)))
854 return -EFAULT;
855 /* FIXME: Should check the copies properly */
856 if (!v.v_vlin)
857 v.v_vlin = vc->vc_scan_lines;
858 if (v.v_clin) {
859 int rows = v.v_vlin/v.v_clin;
860 if (v.v_rows != rows) {
861 if (v.v_rows) /* Parameters don't add up */
862 return -EINVAL;
863 v.v_rows = rows;
864 }
865 }
866 if (v.v_vcol && v.v_ccol) {
867 int cols = v.v_vcol/v.v_ccol;
868 if (v.v_cols != cols) {
869 if (v.v_cols)
870 return -EINVAL;
871 v.v_cols = cols;
872 }
873 }
874
875 if (v.v_clin > 32)
876 return -EINVAL;
877
878 for (i = 0; i < MAX_NR_CONSOLES; i++) {
879 if (!vc_cons[i].d)
880 continue;
881 console_lock();
882 if (v.v_vlin)
883 vc_cons[i].d->vc_scan_lines = v.v_vlin;
884 if (v.v_clin)
885 vc_cons[i].d->vc_font.height = v.v_clin;
886 vc_cons[i].d->vc_resize_user = 1;
887 vc_resize(vc_cons[i].d, v.v_cols, v.v_rows);
888 console_unlock();
889 }
890 break;
891 }
892
893 case PIO_FONT: {
894 if (!perm)
895 return -EPERM;
896 op.op = KD_FONT_OP_SET;
897 op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
898 op.width = 8;
899 op.height = 0;
900 op.charcount = 256;
901 op.data = up;
902 ret = con_font_op(vc_cons[fg_console].d, &op);
903 break;
904 }
905
906 case GIO_FONT: {
907 op.op = KD_FONT_OP_GET;
908 op.flags = KD_FONT_FLAG_OLD;
909 op.width = 8;
910 op.height = 32;
911 op.charcount = 256;
912 op.data = up;
913 ret = con_font_op(vc_cons[fg_console].d, &op);
914 break;
915 }
916
917 case PIO_CMAP:
918 if (!perm)
919 ret = -EPERM;
920 else
921 ret = con_set_cmap(up);
922 break;
923
924 case GIO_CMAP:
925 ret = con_get_cmap(up);
926 break;
927
928 case PIO_FONTX:
929 case GIO_FONTX:
930 ret = do_fontx_ioctl(cmd, up, perm, &op);
931 break;
932
933 case PIO_FONTRESET:
934 {
935 if (!perm)
936 return -EPERM;
937
938#ifdef BROKEN_GRAPHICS_PROGRAMS
939 /* With BROKEN_GRAPHICS_PROGRAMS defined, the default
940 font is not saved. */
941 ret = -ENOSYS;
942 break;
943#else
944 {
945 op.op = KD_FONT_OP_SET_DEFAULT;
946 op.data = NULL;
947 ret = con_font_op(vc_cons[fg_console].d, &op);
948 if (ret)
949 break;
950 console_lock();
951 con_set_default_unimap(vc_cons[fg_console].d);
952 console_unlock();
953 break;
954 }
955#endif
956 }
957
958 case KDFONTOP: {
959 if (copy_from_user(&op, up, sizeof(op))) {
960 ret = -EFAULT;
961 break;
962 }
963 if (!perm && op.op != KD_FONT_OP_GET)
964 return -EPERM;
965 ret = con_font_op(vc, &op);
966 if (ret)
967 break;
968 if (copy_to_user(up, &op, sizeof(op)))
969 ret = -EFAULT;
970 break;
971 }
972
973 case PIO_SCRNMAP:
974 if (!perm)
975 ret = -EPERM;
976 else
977 ret = con_set_trans_old(up);
978 break;
979
980 case GIO_SCRNMAP:
981 ret = con_get_trans_old(up);
982 break;
983
984 case PIO_UNISCRNMAP:
985 if (!perm)
986 ret = -EPERM;
987 else
988 ret = con_set_trans_new(up);
989 break;
990
991 case GIO_UNISCRNMAP:
992 ret = con_get_trans_new(up);
993 break;
994
995 case PIO_UNIMAPCLR:
996 if (!perm)
997 return -EPERM;
998 con_clear_unimap(vc);
999 break;
1000
1001 case PIO_UNIMAP:
1002 case GIO_UNIMAP:
1003 ret = do_unimap_ioctl(cmd, up, perm, vc);
1004 break;
1005
1006 case VT_LOCKSWITCH:
1007 if (!capable(CAP_SYS_TTY_CONFIG))
1008 return -EPERM;
1009 vt_dont_switch = 1;
1010 break;
1011 case VT_UNLOCKSWITCH:
1012 if (!capable(CAP_SYS_TTY_CONFIG))
1013 return -EPERM;
1014 vt_dont_switch = 0;
1015 break;
1016 case VT_GETHIFONTMASK:
1017 ret = put_user(vc->vc_hi_font_mask,
1018 (unsigned short __user *)arg);
1019 break;
1020 case VT_WAITEVENT:
1021 ret = vt_event_wait_ioctl((struct vt_event __user *)arg);
1022 break;
1023 default:
1024 ret = -ENOIOCTLCMD;
1025 }
1026out:
1027 return ret;
1028}
1029
1030void reset_vc(struct vc_data *vc)
1031{
1032 vc->vc_mode = KD_TEXT;
1033 vt_reset_unicode(vc->vc_num);
1034 vc->vt_mode.mode = VT_AUTO;
1035 vc->vt_mode.waitv = 0;
1036 vc->vt_mode.relsig = 0;
1037 vc->vt_mode.acqsig = 0;
1038 vc->vt_mode.frsig = 0;
1039 put_pid(vc->vt_pid);
1040 vc->vt_pid = NULL;
1041 vc->vt_newvt = -1;
1042 if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
1043 reset_palette(vc);
1044}
1045
1046void vc_SAK(struct work_struct *work)
1047{
1048 struct vc *vc_con =
1049 container_of(work, struct vc, SAK_work);
1050 struct vc_data *vc;
1051 struct tty_struct *tty;
1052
1053 console_lock();
1054 vc = vc_con->d;
1055 if (vc) {
1056 /* FIXME: review tty ref counting */
1057 tty = vc->port.tty;
1058 /*
1059 * SAK should also work in all raw modes and reset
1060 * them properly.
1061 */
1062 if (tty)
1063 __do_SAK(tty);
1064 reset_vc(vc);
1065 }
1066 console_unlock();
1067}
1068
1069#ifdef CONFIG_COMPAT
1070
1071struct compat_consolefontdesc {
1072 unsigned short charcount; /* characters in font (256 or 512) */
1073 unsigned short charheight; /* scan lines per character (1-32) */
1074 compat_caddr_t chardata; /* font data in expanded form */
1075};
1076
1077static inline int
1078compat_fontx_ioctl(int cmd, struct compat_consolefontdesc __user *user_cfd,
1079 int perm, struct console_font_op *op)
1080{
1081 struct compat_consolefontdesc cfdarg;
1082 int i;
1083
1084 if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc)))
1085 return -EFAULT;
1086
1087 switch (cmd) {
1088 case PIO_FONTX:
1089 if (!perm)
1090 return -EPERM;
1091 op->op = KD_FONT_OP_SET;
1092 op->flags = KD_FONT_FLAG_OLD;
1093 op->width = 8;
1094 op->height = cfdarg.charheight;
1095 op->charcount = cfdarg.charcount;
1096 op->data = compat_ptr(cfdarg.chardata);
1097 return con_font_op(vc_cons[fg_console].d, op);
1098 case GIO_FONTX:
1099 op->op = KD_FONT_OP_GET;
1100 op->flags = KD_FONT_FLAG_OLD;
1101 op->width = 8;
1102 op->height = cfdarg.charheight;
1103 op->charcount = cfdarg.charcount;
1104 op->data = compat_ptr(cfdarg.chardata);
1105 i = con_font_op(vc_cons[fg_console].d, op);
1106 if (i)
1107 return i;
1108 cfdarg.charheight = op->height;
1109 cfdarg.charcount = op->charcount;
1110 if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc)))
1111 return -EFAULT;
1112 return 0;
1113 }
1114 return -EINVAL;
1115}
1116
1117struct compat_console_font_op {
1118 compat_uint_t op; /* operation code KD_FONT_OP_* */
1119 compat_uint_t flags; /* KD_FONT_FLAG_* */
1120 compat_uint_t width, height; /* font size */
1121 compat_uint_t charcount;
1122 compat_caddr_t data; /* font data with height fixed to 32 */
1123};
1124
1125static inline int
1126compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
1127 int perm, struct console_font_op *op, struct vc_data *vc)
1128{
1129 int i;
1130
1131 if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op)))
1132 return -EFAULT;
1133 if (!perm && op->op != KD_FONT_OP_GET)
1134 return -EPERM;
1135 op->data = compat_ptr(((struct compat_console_font_op *)op)->data);
1136 i = con_font_op(vc, op);
1137 if (i)
1138 return i;
1139 ((struct compat_console_font_op *)op)->data = (unsigned long)op->data;
1140 if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op)))
1141 return -EFAULT;
1142 return 0;
1143}
1144
1145struct compat_unimapdesc {
1146 unsigned short entry_ct;
1147 compat_caddr_t entries;
1148};
1149
1150static inline int
1151compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
1152 int perm, struct vc_data *vc)
1153{
1154 struct compat_unimapdesc tmp;
1155 struct unipair __user *tmp_entries;
1156
1157 if (copy_from_user(&tmp, user_ud, sizeof tmp))
1158 return -EFAULT;
1159 tmp_entries = compat_ptr(tmp.entries);
1160 switch (cmd) {
1161 case PIO_UNIMAP:
1162 if (!perm)
1163 return -EPERM;
1164 return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
1165 case GIO_UNIMAP:
1166 if (!perm && fg_console != vc->vc_num)
1167 return -EPERM;
1168 return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
1169 }
1170 return 0;
1171}
1172
1173long vt_compat_ioctl(struct tty_struct *tty,
1174 unsigned int cmd, unsigned long arg)
1175{
1176 struct vc_data *vc = tty->driver_data;
1177 struct console_font_op op; /* used in multiple places here */
1178 unsigned int console = vc->vc_num;
1179 void __user *up = compat_ptr(arg);
1180 int perm;
1181
1182
1183 if (!vc_cons_allocated(console)) /* impossible? */
1184 return -ENOIOCTLCMD;
1185
1186 /*
1187 * To have permissions to do most of the vt ioctls, we either have
1188 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
1189 */
1190 perm = 0;
1191 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
1192 perm = 1;
1193
1194 switch (cmd) {
1195 /*
1196 * these need special handlers for incompatible data structures
1197 */
1198 case PIO_FONTX:
1199 case GIO_FONTX:
1200 return compat_fontx_ioctl(cmd, up, perm, &op);
1201
1202 case KDFONTOP:
1203 return compat_kdfontop_ioctl(up, perm, &op, vc);
1204
1205 case PIO_UNIMAP:
1206 case GIO_UNIMAP:
1207 return compat_unimap_ioctl(cmd, up, perm, vc);
1208
1209 /*
1210 * all these treat 'arg' as an integer
1211 */
1212 case KIOCSOUND:
1213 case KDMKTONE:
1214#ifdef CONFIG_X86
1215 case KDADDIO:
1216 case KDDELIO:
1217#endif
1218 case KDSETMODE:
1219 case KDMAPDISP:
1220 case KDUNMAPDISP:
1221 case KDSKBMODE:
1222 case KDSKBMETA:
1223 case KDSKBLED:
1224 case KDSETLED:
1225 case KDSIGACCEPT:
1226 case VT_ACTIVATE:
1227 case VT_WAITACTIVE:
1228 case VT_RELDISP:
1229 case VT_DISALLOCATE:
1230 case VT_RESIZE:
1231 case VT_RESIZEX:
1232 return vt_ioctl(tty, cmd, arg);
1233
1234 /*
1235 * the rest has a compatible data structure behind arg,
1236 * but we have to convert it to a proper 64 bit pointer.
1237 */
1238 default:
1239 return vt_ioctl(tty, cmd, (unsigned long)up);
1240 }
1241}
1242
1243
1244#endif /* CONFIG_COMPAT */
1245
1246
1247/*
1248 * Performs the back end of a vt switch. Called under the console
1249 * semaphore.
1250 */
1251static void complete_change_console(struct vc_data *vc)
1252{
1253 unsigned char old_vc_mode;
1254 int old = fg_console;
1255
1256 last_console = fg_console;
1257
1258 /*
1259 * If we're switching, we could be going from KD_GRAPHICS to
1260 * KD_TEXT mode or vice versa, which means we need to blank or
1261 * unblank the screen later.
1262 */
1263 old_vc_mode = vc_cons[fg_console].d->vc_mode;
1264 switch_screen(vc);
1265
1266 /*
1267 * This can't appear below a successful kill_pid(). If it did,
1268 * then the *blank_screen operation could occur while X, having
1269 * received acqsig, is waking up on another processor. This
1270 * condition can lead to overlapping accesses to the VGA range
1271 * and the framebuffer (causing system lockups).
1272 *
1273 * To account for this we duplicate this code below only if the
1274 * controlling process is gone and we've called reset_vc.
1275 */
1276 if (old_vc_mode != vc->vc_mode) {
1277 if (vc->vc_mode == KD_TEXT)
1278 do_unblank_screen(1);
1279 else
1280 do_blank_screen(1);
1281 }
1282
1283 /*
1284 * If this new console is under process control, send it a signal
1285 * telling it that it has acquired. Also check if it has died and
1286 * clean up (similar to logic employed in change_console())
1287 */
1288 if (vc->vt_mode.mode == VT_PROCESS) {
1289 /*
1290 * Send the signal as privileged - kill_pid() will
1291 * tell us if the process has gone or something else
1292 * is awry
1293 */
1294 if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
1295 /*
1296 * The controlling process has died, so we revert back to
1297 * normal operation. In this case, we'll also change back
1298 * to KD_TEXT mode. I'm not sure if this is strictly correct
1299 * but it saves the agony when the X server dies and the screen
1300 * remains blanked due to KD_GRAPHICS! It would be nice to do
1301 * this outside of VT_PROCESS but there is no single process
1302 * to account for and tracking tty count may be undesirable.
1303 */
1304 reset_vc(vc);
1305
1306 if (old_vc_mode != vc->vc_mode) {
1307 if (vc->vc_mode == KD_TEXT)
1308 do_unblank_screen(1);
1309 else
1310 do_blank_screen(1);
1311 }
1312 }
1313 }
1314
1315 /*
1316 * Wake anyone waiting for their VT to activate
1317 */
1318 vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num);
1319 return;
1320}
1321
1322/*
1323 * Performs the front-end of a vt switch
1324 */
1325void change_console(struct vc_data *new_vc)
1326{
1327 struct vc_data *vc;
1328
1329 if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
1330 return;
1331
1332 /*
1333 * If this vt is in process mode, then we need to handshake with
1334 * that process before switching. Essentially, we store where that
1335 * vt wants to switch to and wait for it to tell us when it's done
1336 * (via VT_RELDISP ioctl).
1337 *
1338 * We also check to see if the controlling process still exists.
1339 * If it doesn't, we reset this vt to auto mode and continue.
1340 * This is a cheap way to track process control. The worst thing
1341 * that can happen is: we send a signal to a process, it dies, and
1342 * the switch gets "lost" waiting for a response; hopefully, the
1343 * user will try again, we'll detect the process is gone (unless
1344 * the user waits just the right amount of time :-) and revert the
1345 * vt to auto control.
1346 */
1347 vc = vc_cons[fg_console].d;
1348 if (vc->vt_mode.mode == VT_PROCESS) {
1349 /*
1350 * Send the signal as privileged - kill_pid() will
1351 * tell us if the process has gone or something else
1352 * is awry.
1353 *
1354 * We need to set vt_newvt *before* sending the signal or we
1355 * have a race.
1356 */
1357 vc->vt_newvt = new_vc->vc_num;
1358 if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
1359 /*
1360 * It worked. Mark the vt to switch to and
1361 * return. The process needs to send us a
1362 * VT_RELDISP ioctl to complete the switch.
1363 */
1364 return;
1365 }
1366
1367 /*
1368 * The controlling process has died, so we revert back to
1369 * normal operation. In this case, we'll also change back
1370 * to KD_TEXT mode. I'm not sure if this is strictly correct
1371 * but it saves the agony when the X server dies and the screen
1372 * remains blanked due to KD_GRAPHICS! It would be nice to do
1373 * this outside of VT_PROCESS but there is no single process
1374 * to account for and tracking tty count may be undesirable.
1375 */
1376 reset_vc(vc);
1377
1378 /*
1379 * Fall through to normal (VT_AUTO) handling of the switch...
1380 */
1381 }
1382
1383 /*
1384 * Ignore all switches in KD_GRAPHICS+VT_AUTO mode
1385 */
1386 if (vc->vc_mode == KD_GRAPHICS)
1387 return;
1388
1389 complete_change_console(new_vc);
1390}
1391
1392/* Perform a kernel triggered VT switch for suspend/resume */
1393
1394static int disable_vt_switch;
1395
1396int vt_move_to_console(unsigned int vt, int alloc)
1397{
1398 int prev;
1399
1400 console_lock();
1401 /* Graphics mode - up to X */
1402 if (disable_vt_switch) {
1403 console_unlock();
1404 return 0;
1405 }
1406 prev = fg_console;
1407
1408 if (alloc && vc_allocate(vt)) {
1409 /* we can't have a free VC for now. Too bad,
1410 * we don't want to mess the screen for now. */
1411 console_unlock();
1412 return -ENOSPC;
1413 }
1414
1415 if (set_console(vt)) {
1416 /*
1417 * We're unable to switch to the SUSPEND_CONSOLE.
1418 * Let the calling function know so it can decide
1419 * what to do.
1420 */
1421 console_unlock();
1422 return -EIO;
1423 }
1424 console_unlock();
1425 if (vt_waitactive(vt + 1)) {
1426 pr_debug("Suspend: Can't switch VCs.");
1427 return -EINTR;
1428 }
1429 return prev;
1430}
1431
1432/*
1433 * Normally during a suspend, we allocate a new console and switch to it.
1434 * When we resume, we switch back to the original console. This switch
1435 * can be slow, so on systems where the framebuffer can handle restoration
1436 * of video registers anyways, there's little point in doing the console
1437 * switch. This function allows you to disable it by passing it '0'.
1438 */
1439void pm_set_vt_switch(int do_switch)
1440{
1441 console_lock();
1442 disable_vt_switch = !do_switch;
1443 console_unlock();
1444}
1445EXPORT_SYMBOL(pm_set_vt_switch);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 1992 obz under the linux copyright
4 *
5 * Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
6 * Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
7 * Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
8 * Some code moved for less code duplication - Andi Kleen - Mar 1997
9 * Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
10 */
11
12#include <linux/types.h>
13#include <linux/errno.h>
14#include <linux/sched/signal.h>
15#include <linux/tty.h>
16#include <linux/timer.h>
17#include <linux/kernel.h>
18#include <linux/compat.h>
19#include <linux/module.h>
20#include <linux/kd.h>
21#include <linux/vt.h>
22#include <linux/string.h>
23#include <linux/slab.h>
24#include <linux/major.h>
25#include <linux/fs.h>
26#include <linux/console.h>
27#include <linux/consolemap.h>
28#include <linux/signal.h>
29#include <linux/suspend.h>
30#include <linux/timex.h>
31
32#include <asm/io.h>
33#include <linux/uaccess.h>
34
35#include <linux/nospec.h>
36
37#include <linux/kbd_kern.h>
38#include <linux/vt_kern.h>
39#include <linux/kbd_diacr.h>
40#include <linux/selection.h>
41
42bool vt_dont_switch;
43
44static inline bool vt_in_use(unsigned int i)
45{
46 const struct vc_data *vc = vc_cons[i].d;
47
48 /*
49 * console_lock must be held to prevent the vc from being deallocated
50 * while we're checking whether it's in-use.
51 */
52 WARN_CONSOLE_UNLOCKED();
53
54 return vc && kref_read(&vc->port.kref) > 1;
55}
56
57static inline bool vt_busy(int i)
58{
59 if (vt_in_use(i))
60 return true;
61 if (i == fg_console)
62 return true;
63 if (vc_is_sel(vc_cons[i].d))
64 return true;
65
66 return false;
67}
68
69/*
70 * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
71 * experimentation and study of X386 SYSV handling.
72 *
73 * One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
74 * /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
75 * and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
76 * always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
77 * ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
78 * /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
79 * to the current console is done by the main ioctl code.
80 */
81
82#ifdef CONFIG_X86
83#include <asm/syscalls.h>
84#endif
85
86static void complete_change_console(struct vc_data *vc);
87
88/*
89 * User space VT_EVENT handlers
90 */
91
92struct vt_event_wait {
93 struct list_head list;
94 struct vt_event event;
95 int done;
96};
97
98static LIST_HEAD(vt_events);
99static DEFINE_SPINLOCK(vt_event_lock);
100static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue);
101
102/**
103 * vt_event_post
104 * @event: the event that occurred
105 * @old: old console
106 * @new: new console
107 *
108 * Post an VT event to interested VT handlers
109 */
110
111void vt_event_post(unsigned int event, unsigned int old, unsigned int new)
112{
113 struct list_head *pos, *head;
114 unsigned long flags;
115 int wake = 0;
116
117 spin_lock_irqsave(&vt_event_lock, flags);
118 head = &vt_events;
119
120 list_for_each(pos, head) {
121 struct vt_event_wait *ve = list_entry(pos,
122 struct vt_event_wait, list);
123 if (!(ve->event.event & event))
124 continue;
125 ve->event.event = event;
126 /* kernel view is consoles 0..n-1, user space view is
127 console 1..n with 0 meaning current, so we must bias */
128 ve->event.oldev = old + 1;
129 ve->event.newev = new + 1;
130 wake = 1;
131 ve->done = 1;
132 }
133 spin_unlock_irqrestore(&vt_event_lock, flags);
134 if (wake)
135 wake_up_interruptible(&vt_event_waitqueue);
136}
137
138static void __vt_event_queue(struct vt_event_wait *vw)
139{
140 unsigned long flags;
141 /* Prepare the event */
142 INIT_LIST_HEAD(&vw->list);
143 vw->done = 0;
144 /* Queue our event */
145 spin_lock_irqsave(&vt_event_lock, flags);
146 list_add(&vw->list, &vt_events);
147 spin_unlock_irqrestore(&vt_event_lock, flags);
148}
149
150static void __vt_event_wait(struct vt_event_wait *vw)
151{
152 /* Wait for it to pass */
153 wait_event_interruptible(vt_event_waitqueue, vw->done);
154}
155
156static void __vt_event_dequeue(struct vt_event_wait *vw)
157{
158 unsigned long flags;
159
160 /* Dequeue it */
161 spin_lock_irqsave(&vt_event_lock, flags);
162 list_del(&vw->list);
163 spin_unlock_irqrestore(&vt_event_lock, flags);
164}
165
166/**
167 * vt_event_wait - wait for an event
168 * @vw: our event
169 *
170 * Waits for an event to occur which completes our vt_event_wait
171 * structure. On return the structure has wv->done set to 1 for success
172 * or 0 if some event such as a signal ended the wait.
173 */
174
175static void vt_event_wait(struct vt_event_wait *vw)
176{
177 __vt_event_queue(vw);
178 __vt_event_wait(vw);
179 __vt_event_dequeue(vw);
180}
181
182/**
183 * vt_event_wait_ioctl - event ioctl handler
184 * @event: argument to ioctl (the event)
185 *
186 * Implement the VT_WAITEVENT ioctl using the VT event interface
187 */
188
189static int vt_event_wait_ioctl(struct vt_event __user *event)
190{
191 struct vt_event_wait vw;
192
193 if (copy_from_user(&vw.event, event, sizeof(struct vt_event)))
194 return -EFAULT;
195 /* Highest supported event for now */
196 if (vw.event.event & ~VT_MAX_EVENT)
197 return -EINVAL;
198
199 vt_event_wait(&vw);
200 /* If it occurred report it */
201 if (vw.done) {
202 if (copy_to_user(event, &vw.event, sizeof(struct vt_event)))
203 return -EFAULT;
204 return 0;
205 }
206 return -EINTR;
207}
208
209/**
210 * vt_waitactive - active console wait
211 * @n: new console
212 *
213 * Helper for event waits. Used to implement the legacy
214 * event waiting ioctls in terms of events
215 */
216
217int vt_waitactive(int n)
218{
219 struct vt_event_wait vw;
220 do {
221 vw.event.event = VT_EVENT_SWITCH;
222 __vt_event_queue(&vw);
223 if (n == fg_console + 1) {
224 __vt_event_dequeue(&vw);
225 break;
226 }
227 __vt_event_wait(&vw);
228 __vt_event_dequeue(&vw);
229 if (vw.done == 0)
230 return -EINTR;
231 } while (vw.event.newev != n);
232 return 0;
233}
234
235/*
236 * these are the valid i/o ports we're allowed to change. they map all the
237 * video ports
238 */
239#define GPFIRST 0x3b4
240#define GPLAST 0x3df
241#define GPNUM (GPLAST - GPFIRST + 1)
242
243/*
244 * currently, setting the mode from KD_TEXT to KD_GRAPHICS doesn't do a whole
245 * lot. i'm not sure if it should do any restoration of modes or what...
246 *
247 * XXX It should at least call into the driver, fbdev's definitely need to
248 * restore their engine state. --BenH
249 *
250 * Called with the console lock held.
251 */
252static int vt_kdsetmode(struct vc_data *vc, unsigned long mode)
253{
254 switch (mode) {
255 case KD_GRAPHICS:
256 break;
257 case KD_TEXT0:
258 case KD_TEXT1:
259 mode = KD_TEXT;
260 fallthrough;
261 case KD_TEXT:
262 break;
263 default:
264 return -EINVAL;
265 }
266
267 if (vc->vc_mode == mode)
268 return 0;
269
270 vc->vc_mode = mode;
271 if (vc->vc_num != fg_console)
272 return 0;
273
274 /* explicitly blank/unblank the screen if switching modes */
275 if (mode == KD_TEXT)
276 do_unblank_screen(1);
277 else
278 do_blank_screen(1);
279
280 return 0;
281}
282
283static int vt_k_ioctl(struct tty_struct *tty, unsigned int cmd,
284 unsigned long arg, bool perm)
285{
286 struct vc_data *vc = tty->driver_data;
287 void __user *up = (void __user *)arg;
288 unsigned int console = vc->vc_num;
289 int ret;
290
291 switch (cmd) {
292 case KIOCSOUND:
293 if (!perm)
294 return -EPERM;
295 /*
296 * The use of PIT_TICK_RATE is historic, it used to be
297 * the platform-dependent CLOCK_TICK_RATE between 2.6.12
298 * and 2.6.36, which was a minor but unfortunate ABI
299 * change. kd_mksound is locked by the input layer.
300 */
301 if (arg)
302 arg = PIT_TICK_RATE / arg;
303 kd_mksound(arg, 0);
304 break;
305
306 case KDMKTONE:
307 if (!perm)
308 return -EPERM;
309 {
310 unsigned int ticks, count;
311
312 /*
313 * Generate the tone for the appropriate number of ticks.
314 * If the time is zero, turn off sound ourselves.
315 */
316 ticks = msecs_to_jiffies((arg >> 16) & 0xffff);
317 count = ticks ? (arg & 0xffff) : 0;
318 if (count)
319 count = PIT_TICK_RATE / count;
320 kd_mksound(count, ticks);
321 break;
322 }
323
324 case KDGKBTYPE:
325 /*
326 * this is naïve.
327 */
328 return put_user(KB_101, (char __user *)arg);
329
330 /*
331 * These cannot be implemented on any machine that implements
332 * ioperm() in user level (such as Alpha PCs) or not at all.
333 *
334 * XXX: you should never use these, just call ioperm directly..
335 */
336#ifdef CONFIG_X86
337 case KDADDIO:
338 case KDDELIO:
339 /*
340 * KDADDIO and KDDELIO may be able to add ports beyond what
341 * we reject here, but to be safe...
342 *
343 * These are locked internally via sys_ioperm
344 */
345 if (arg < GPFIRST || arg > GPLAST)
346 return -EINVAL;
347
348 return ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
349
350 case KDENABIO:
351 case KDDISABIO:
352 return ksys_ioperm(GPFIRST, GPNUM,
353 (cmd == KDENABIO)) ? -ENXIO : 0;
354#endif
355
356 /* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
357
358 case KDKBDREP:
359 {
360 struct kbd_repeat kbrep;
361
362 if (!capable(CAP_SYS_TTY_CONFIG))
363 return -EPERM;
364
365 if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat)))
366 return -EFAULT;
367
368 ret = kbd_rate(&kbrep);
369 if (ret)
370 return ret;
371 if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
372 return -EFAULT;
373 break;
374 }
375
376 case KDSETMODE:
377 if (!perm)
378 return -EPERM;
379
380 console_lock();
381 ret = vt_kdsetmode(vc, arg);
382 console_unlock();
383 return ret;
384
385 case KDGETMODE:
386 return put_user(vc->vc_mode, (int __user *)arg);
387
388 case KDMAPDISP:
389 case KDUNMAPDISP:
390 /*
391 * these work like a combination of mmap and KDENABIO.
392 * this could be easily finished.
393 */
394 return -EINVAL;
395
396 case KDSKBMODE:
397 if (!perm)
398 return -EPERM;
399 ret = vt_do_kdskbmode(console, arg);
400 if (ret)
401 return ret;
402 tty_ldisc_flush(tty);
403 break;
404
405 case KDGKBMODE:
406 return put_user(vt_do_kdgkbmode(console), (int __user *)arg);
407
408 /* this could be folded into KDSKBMODE, but for compatibility
409 reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
410 case KDSKBMETA:
411 return vt_do_kdskbmeta(console, arg);
412
413 case KDGKBMETA:
414 /* FIXME: should review whether this is worth locking */
415 return put_user(vt_do_kdgkbmeta(console), (int __user *)arg);
416
417 case KDGETKEYCODE:
418 case KDSETKEYCODE:
419 if(!capable(CAP_SYS_TTY_CONFIG))
420 perm = 0;
421 return vt_do_kbkeycode_ioctl(cmd, up, perm);
422
423 case KDGKBENT:
424 case KDSKBENT:
425 return vt_do_kdsk_ioctl(cmd, up, perm, console);
426
427 case KDGKBSENT:
428 case KDSKBSENT:
429 return vt_do_kdgkb_ioctl(cmd, up, perm);
430
431 /* Diacritical processing. Handled in keyboard.c as it has
432 to operate on the keyboard locks and structures */
433 case KDGKBDIACR:
434 case KDGKBDIACRUC:
435 case KDSKBDIACR:
436 case KDSKBDIACRUC:
437 return vt_do_diacrit(cmd, up, perm);
438
439 /* the ioctls below read/set the flags usually shown in the leds */
440 /* don't use them - they will go away without warning */
441 case KDGKBLED:
442 case KDSKBLED:
443 case KDGETLED:
444 case KDSETLED:
445 return vt_do_kdskled(console, cmd, arg, perm);
446
447 /*
448 * A process can indicate its willingness to accept signals
449 * generated by pressing an appropriate key combination.
450 * Thus, one can have a daemon that e.g. spawns a new console
451 * upon a keypress and then changes to it.
452 * See also the kbrequest field of inittab(5).
453 */
454 case KDSIGACCEPT:
455 if (!perm || !capable(CAP_KILL))
456 return -EPERM;
457 if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
458 return -EINVAL;
459
460 spin_lock_irq(&vt_spawn_con.lock);
461 put_pid(vt_spawn_con.pid);
462 vt_spawn_con.pid = get_pid(task_pid(current));
463 vt_spawn_con.sig = arg;
464 spin_unlock_irq(&vt_spawn_con.lock);
465 break;
466
467 case KDFONTOP: {
468 struct console_font_op op;
469
470 if (copy_from_user(&op, up, sizeof(op)))
471 return -EFAULT;
472 if (!perm && op.op != KD_FONT_OP_GET)
473 return -EPERM;
474 ret = con_font_op(vc, &op);
475 if (ret)
476 return ret;
477 if (copy_to_user(up, &op, sizeof(op)))
478 return -EFAULT;
479 break;
480 }
481
482 default:
483 return -ENOIOCTLCMD;
484 }
485
486 return 0;
487}
488
489static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
490 bool perm, struct vc_data *vc)
491{
492 struct unimapdesc tmp;
493
494 if (copy_from_user(&tmp, user_ud, sizeof tmp))
495 return -EFAULT;
496 switch (cmd) {
497 case PIO_UNIMAP:
498 if (!perm)
499 return -EPERM;
500 return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
501 case GIO_UNIMAP:
502 if (!perm && fg_console != vc->vc_num)
503 return -EPERM;
504 return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct),
505 tmp.entries);
506 }
507 return 0;
508}
509
510static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
511 bool perm)
512{
513 switch (cmd) {
514 case PIO_CMAP:
515 if (!perm)
516 return -EPERM;
517 return con_set_cmap(up);
518
519 case GIO_CMAP:
520 return con_get_cmap(up);
521
522 case PIO_SCRNMAP:
523 if (!perm)
524 return -EPERM;
525 return con_set_trans_old(up);
526
527 case GIO_SCRNMAP:
528 return con_get_trans_old(up);
529
530 case PIO_UNISCRNMAP:
531 if (!perm)
532 return -EPERM;
533 return con_set_trans_new(up);
534
535 case GIO_UNISCRNMAP:
536 return con_get_trans_new(up);
537
538 case PIO_UNIMAPCLR:
539 if (!perm)
540 return -EPERM;
541 con_clear_unimap(vc);
542 break;
543
544 case PIO_UNIMAP:
545 case GIO_UNIMAP:
546 return do_unimap_ioctl(cmd, up, perm, vc);
547
548 default:
549 return -ENOIOCTLCMD;
550 }
551
552 return 0;
553}
554
555static int vt_reldisp(struct vc_data *vc, unsigned int swtch)
556{
557 int newvt, ret;
558
559 if (vc->vt_mode.mode != VT_PROCESS)
560 return -EINVAL;
561
562 /* Switched-to response */
563 if (vc->vt_newvt < 0) {
564 /* If it's just an ACK, ignore it */
565 return swtch == VT_ACKACQ ? 0 : -EINVAL;
566 }
567
568 /* Switching-from response */
569 if (swtch == 0) {
570 /* Switch disallowed, so forget we were trying to do it. */
571 vc->vt_newvt = -1;
572 return 0;
573 }
574
575 /* The current vt has been released, so complete the switch. */
576 newvt = vc->vt_newvt;
577 vc->vt_newvt = -1;
578 ret = vc_allocate(newvt);
579 if (ret)
580 return ret;
581
582 /*
583 * When we actually do the console switch, make sure we are atomic with
584 * respect to other console switches..
585 */
586 complete_change_console(vc_cons[newvt].d);
587
588 return 0;
589}
590
591static int vt_setactivate(struct vt_setactivate __user *sa)
592{
593 struct vt_setactivate vsa;
594 struct vc_data *nvc;
595 int ret;
596
597 if (copy_from_user(&vsa, sa, sizeof(vsa)))
598 return -EFAULT;
599 if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
600 return -ENXIO;
601
602 vsa.console--;
603 vsa.console = array_index_nospec(vsa.console, MAX_NR_CONSOLES);
604 console_lock();
605 ret = vc_allocate(vsa.console);
606 if (ret) {
607 console_unlock();
608 return ret;
609 }
610
611 /*
612 * This is safe providing we don't drop the console sem between
613 * vc_allocate and finishing referencing nvc.
614 */
615 nvc = vc_cons[vsa.console].d;
616 nvc->vt_mode = vsa.mode;
617 nvc->vt_mode.frsig = 0;
618 put_pid(nvc->vt_pid);
619 nvc->vt_pid = get_pid(task_pid(current));
620 console_unlock();
621
622 /* Commence switch and lock */
623 /* Review set_console locks */
624 set_console(vsa.console);
625
626 return 0;
627}
628
629/* deallocate a single console, if possible (leave 0) */
630static int vt_disallocate(unsigned int vc_num)
631{
632 struct vc_data *vc = NULL;
633 int ret = 0;
634
635 console_lock();
636 if (vt_busy(vc_num))
637 ret = -EBUSY;
638 else if (vc_num)
639 vc = vc_deallocate(vc_num);
640 console_unlock();
641
642 if (vc && vc_num >= MIN_NR_CONSOLES)
643 tty_port_put(&vc->port);
644
645 return ret;
646}
647
648/* deallocate all unused consoles, but leave 0 */
649static void vt_disallocate_all(void)
650{
651 struct vc_data *vc[MAX_NR_CONSOLES];
652 int i;
653
654 console_lock();
655 for (i = 1; i < MAX_NR_CONSOLES; i++)
656 if (!vt_busy(i))
657 vc[i] = vc_deallocate(i);
658 else
659 vc[i] = NULL;
660 console_unlock();
661
662 for (i = 1; i < MAX_NR_CONSOLES; i++) {
663 if (vc[i] && i >= MIN_NR_CONSOLES)
664 tty_port_put(&vc[i]->port);
665 }
666}
667
668static int vt_resizex(struct vc_data *vc, struct vt_consize __user *cs)
669{
670 struct vt_consize v;
671 int i;
672
673 if (copy_from_user(&v, cs, sizeof(struct vt_consize)))
674 return -EFAULT;
675
676 /* FIXME: Should check the copies properly */
677 if (!v.v_vlin)
678 v.v_vlin = vc->vc_scan_lines;
679
680 if (v.v_clin) {
681 int rows = v.v_vlin / v.v_clin;
682 if (v.v_rows != rows) {
683 if (v.v_rows) /* Parameters don't add up */
684 return -EINVAL;
685 v.v_rows = rows;
686 }
687 }
688
689 if (v.v_vcol && v.v_ccol) {
690 int cols = v.v_vcol / v.v_ccol;
691 if (v.v_cols != cols) {
692 if (v.v_cols)
693 return -EINVAL;
694 v.v_cols = cols;
695 }
696 }
697
698 if (v.v_clin > 32)
699 return -EINVAL;
700
701 for (i = 0; i < MAX_NR_CONSOLES; i++) {
702 struct vc_data *vcp;
703
704 if (!vc_cons[i].d)
705 continue;
706 console_lock();
707 vcp = vc_cons[i].d;
708 if (vcp) {
709 int ret;
710 int save_scan_lines = vcp->vc_scan_lines;
711 int save_cell_height = vcp->vc_cell_height;
712
713 if (v.v_vlin)
714 vcp->vc_scan_lines = v.v_vlin;
715 if (v.v_clin)
716 vcp->vc_cell_height = v.v_clin;
717 ret = __vc_resize(vcp, v.v_cols, v.v_rows, true);
718 if (ret) {
719 vcp->vc_scan_lines = save_scan_lines;
720 vcp->vc_cell_height = save_cell_height;
721 console_unlock();
722 return ret;
723 }
724 }
725 console_unlock();
726 }
727
728 return 0;
729}
730
731/*
732 * We handle the console-specific ioctl's here. We allow the
733 * capability to modify any console, not just the fg_console.
734 */
735int vt_ioctl(struct tty_struct *tty,
736 unsigned int cmd, unsigned long arg)
737{
738 struct vc_data *vc = tty->driver_data;
739 void __user *up = (void __user *)arg;
740 int i, perm;
741 int ret;
742
743 /*
744 * To have permissions to do most of the vt ioctls, we either have
745 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
746 */
747 perm = 0;
748 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
749 perm = 1;
750
751 ret = vt_k_ioctl(tty, cmd, arg, perm);
752 if (ret != -ENOIOCTLCMD)
753 return ret;
754
755 ret = vt_io_ioctl(vc, cmd, up, perm);
756 if (ret != -ENOIOCTLCMD)
757 return ret;
758
759 switch (cmd) {
760 case TIOCLINUX:
761 return tioclinux(tty, arg);
762 case VT_SETMODE:
763 {
764 struct vt_mode tmp;
765
766 if (!perm)
767 return -EPERM;
768 if (copy_from_user(&tmp, up, sizeof(struct vt_mode)))
769 return -EFAULT;
770 if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS)
771 return -EINVAL;
772
773 console_lock();
774 vc->vt_mode = tmp;
775 /* the frsig is ignored, so we set it to 0 */
776 vc->vt_mode.frsig = 0;
777 put_pid(vc->vt_pid);
778 vc->vt_pid = get_pid(task_pid(current));
779 /* no switch is required -- saw@shade.msu.ru */
780 vc->vt_newvt = -1;
781 console_unlock();
782 break;
783 }
784
785 case VT_GETMODE:
786 {
787 struct vt_mode tmp;
788 int rc;
789
790 console_lock();
791 memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
792 console_unlock();
793
794 rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
795 if (rc)
796 return -EFAULT;
797 break;
798 }
799
800 /*
801 * Returns global vt state. Note that VT 0 is always open, since
802 * it's an alias for the current VT, and people can't use it here.
803 * We cannot return state for more than 16 VTs, since v_state is short.
804 */
805 case VT_GETSTATE:
806 {
807 struct vt_stat __user *vtstat = up;
808 unsigned short state, mask;
809
810 if (put_user(fg_console + 1, &vtstat->v_active))
811 return -EFAULT;
812
813 state = 1; /* /dev/tty0 is always open */
814 console_lock(); /* required by vt_in_use() */
815 for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
816 ++i, mask <<= 1)
817 if (vt_in_use(i))
818 state |= mask;
819 console_unlock();
820 return put_user(state, &vtstat->v_state);
821 }
822
823 /*
824 * Returns the first available (non-opened) console.
825 */
826 case VT_OPENQRY:
827 console_lock(); /* required by vt_in_use() */
828 for (i = 0; i < MAX_NR_CONSOLES; ++i)
829 if (!vt_in_use(i))
830 break;
831 console_unlock();
832 i = i < MAX_NR_CONSOLES ? (i+1) : -1;
833 return put_user(i, (int __user *)arg);
834
835 /*
836 * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
837 * with num >= 1 (switches to vt 0, our console, are not allowed, just
838 * to preserve sanity).
839 */
840 case VT_ACTIVATE:
841 if (!perm)
842 return -EPERM;
843 if (arg == 0 || arg > MAX_NR_CONSOLES)
844 return -ENXIO;
845
846 arg--;
847 arg = array_index_nospec(arg, MAX_NR_CONSOLES);
848 console_lock();
849 ret = vc_allocate(arg);
850 console_unlock();
851 if (ret)
852 return ret;
853 set_console(arg);
854 break;
855
856 case VT_SETACTIVATE:
857 if (!perm)
858 return -EPERM;
859
860 return vt_setactivate(up);
861
862 /*
863 * wait until the specified VT has been activated
864 */
865 case VT_WAITACTIVE:
866 if (!perm)
867 return -EPERM;
868 if (arg == 0 || arg > MAX_NR_CONSOLES)
869 return -ENXIO;
870 return vt_waitactive(arg);
871
872 /*
873 * If a vt is under process control, the kernel will not switch to it
874 * immediately, but postpone the operation until the process calls this
875 * ioctl, allowing the switch to complete.
876 *
877 * According to the X sources this is the behavior:
878 * 0: pending switch-from not OK
879 * 1: pending switch-from OK
880 * 2: completed switch-to OK
881 */
882 case VT_RELDISP:
883 if (!perm)
884 return -EPERM;
885
886 console_lock();
887 ret = vt_reldisp(vc, arg);
888 console_unlock();
889
890 return ret;
891
892
893 /*
894 * Disallocate memory associated to VT (but leave VT1)
895 */
896 case VT_DISALLOCATE:
897 if (arg > MAX_NR_CONSOLES)
898 return -ENXIO;
899
900 if (arg == 0) {
901 vt_disallocate_all();
902 break;
903 }
904
905 arg = array_index_nospec(arg - 1, MAX_NR_CONSOLES);
906 return vt_disallocate(arg);
907
908 case VT_RESIZE:
909 {
910 struct vt_sizes __user *vtsizes = up;
911 struct vc_data *vc;
912 ushort ll,cc;
913
914 if (!perm)
915 return -EPERM;
916 if (get_user(ll, &vtsizes->v_rows) ||
917 get_user(cc, &vtsizes->v_cols))
918 return -EFAULT;
919
920 console_lock();
921 for (i = 0; i < MAX_NR_CONSOLES; i++) {
922 vc = vc_cons[i].d;
923
924 if (vc) {
925 /* FIXME: review v tty lock */
926 __vc_resize(vc_cons[i].d, cc, ll, true);
927 }
928 }
929 console_unlock();
930 break;
931 }
932
933 case VT_RESIZEX:
934 if (!perm)
935 return -EPERM;
936
937 return vt_resizex(vc, up);
938
939 case VT_LOCKSWITCH:
940 if (!capable(CAP_SYS_TTY_CONFIG))
941 return -EPERM;
942 vt_dont_switch = true;
943 break;
944 case VT_UNLOCKSWITCH:
945 if (!capable(CAP_SYS_TTY_CONFIG))
946 return -EPERM;
947 vt_dont_switch = false;
948 break;
949 case VT_GETHIFONTMASK:
950 return put_user(vc->vc_hi_font_mask,
951 (unsigned short __user *)arg);
952 case VT_WAITEVENT:
953 return vt_event_wait_ioctl((struct vt_event __user *)arg);
954 default:
955 return -ENOIOCTLCMD;
956 }
957
958 return 0;
959}
960
961void reset_vc(struct vc_data *vc)
962{
963 vc->vc_mode = KD_TEXT;
964 vt_reset_unicode(vc->vc_num);
965 vc->vt_mode.mode = VT_AUTO;
966 vc->vt_mode.waitv = 0;
967 vc->vt_mode.relsig = 0;
968 vc->vt_mode.acqsig = 0;
969 vc->vt_mode.frsig = 0;
970 put_pid(vc->vt_pid);
971 vc->vt_pid = NULL;
972 vc->vt_newvt = -1;
973 reset_palette(vc);
974}
975
976void vc_SAK(struct work_struct *work)
977{
978 struct vc *vc_con =
979 container_of(work, struct vc, SAK_work);
980 struct vc_data *vc;
981 struct tty_struct *tty;
982
983 console_lock();
984 vc = vc_con->d;
985 if (vc) {
986 /* FIXME: review tty ref counting */
987 tty = vc->port.tty;
988 /*
989 * SAK should also work in all raw modes and reset
990 * them properly.
991 */
992 if (tty)
993 __do_SAK(tty);
994 reset_vc(vc);
995 }
996 console_unlock();
997}
998
999#ifdef CONFIG_COMPAT
1000
1001struct compat_console_font_op {
1002 compat_uint_t op; /* operation code KD_FONT_OP_* */
1003 compat_uint_t flags; /* KD_FONT_FLAG_* */
1004 compat_uint_t width, height; /* font size */
1005 compat_uint_t charcount;
1006 compat_caddr_t data; /* font data with height fixed to 32 */
1007};
1008
1009static inline int
1010compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
1011 int perm, struct console_font_op *op, struct vc_data *vc)
1012{
1013 int i;
1014
1015 if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op)))
1016 return -EFAULT;
1017 if (!perm && op->op != KD_FONT_OP_GET)
1018 return -EPERM;
1019 op->data = compat_ptr(((struct compat_console_font_op *)op)->data);
1020 i = con_font_op(vc, op);
1021 if (i)
1022 return i;
1023 ((struct compat_console_font_op *)op)->data = (unsigned long)op->data;
1024 if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op)))
1025 return -EFAULT;
1026 return 0;
1027}
1028
1029struct compat_unimapdesc {
1030 unsigned short entry_ct;
1031 compat_caddr_t entries;
1032};
1033
1034static inline int
1035compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
1036 int perm, struct vc_data *vc)
1037{
1038 struct compat_unimapdesc tmp;
1039 struct unipair __user *tmp_entries;
1040
1041 if (copy_from_user(&tmp, user_ud, sizeof tmp))
1042 return -EFAULT;
1043 tmp_entries = compat_ptr(tmp.entries);
1044 switch (cmd) {
1045 case PIO_UNIMAP:
1046 if (!perm)
1047 return -EPERM;
1048 return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
1049 case GIO_UNIMAP:
1050 if (!perm && fg_console != vc->vc_num)
1051 return -EPERM;
1052 return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
1053 }
1054 return 0;
1055}
1056
1057long vt_compat_ioctl(struct tty_struct *tty,
1058 unsigned int cmd, unsigned long arg)
1059{
1060 struct vc_data *vc = tty->driver_data;
1061 struct console_font_op op; /* used in multiple places here */
1062 void __user *up = compat_ptr(arg);
1063 int perm;
1064
1065 /*
1066 * To have permissions to do most of the vt ioctls, we either have
1067 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
1068 */
1069 perm = 0;
1070 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
1071 perm = 1;
1072
1073 switch (cmd) {
1074 /*
1075 * these need special handlers for incompatible data structures
1076 */
1077
1078 case KDFONTOP:
1079 return compat_kdfontop_ioctl(up, perm, &op, vc);
1080
1081 case PIO_UNIMAP:
1082 case GIO_UNIMAP:
1083 return compat_unimap_ioctl(cmd, up, perm, vc);
1084
1085 /*
1086 * all these treat 'arg' as an integer
1087 */
1088 case KIOCSOUND:
1089 case KDMKTONE:
1090#ifdef CONFIG_X86
1091 case KDADDIO:
1092 case KDDELIO:
1093#endif
1094 case KDSETMODE:
1095 case KDMAPDISP:
1096 case KDUNMAPDISP:
1097 case KDSKBMODE:
1098 case KDSKBMETA:
1099 case KDSKBLED:
1100 case KDSETLED:
1101 case KDSIGACCEPT:
1102 case VT_ACTIVATE:
1103 case VT_WAITACTIVE:
1104 case VT_RELDISP:
1105 case VT_DISALLOCATE:
1106 case VT_RESIZE:
1107 case VT_RESIZEX:
1108 return vt_ioctl(tty, cmd, arg);
1109
1110 /*
1111 * the rest has a compatible data structure behind arg,
1112 * but we have to convert it to a proper 64 bit pointer.
1113 */
1114 default:
1115 return vt_ioctl(tty, cmd, (unsigned long)up);
1116 }
1117}
1118
1119
1120#endif /* CONFIG_COMPAT */
1121
1122
1123/*
1124 * Performs the back end of a vt switch. Called under the console
1125 * semaphore.
1126 */
1127static void complete_change_console(struct vc_data *vc)
1128{
1129 unsigned char old_vc_mode;
1130 int old = fg_console;
1131
1132 last_console = fg_console;
1133
1134 /*
1135 * If we're switching, we could be going from KD_GRAPHICS to
1136 * KD_TEXT mode or vice versa, which means we need to blank or
1137 * unblank the screen later.
1138 */
1139 old_vc_mode = vc_cons[fg_console].d->vc_mode;
1140 switch_screen(vc);
1141
1142 /*
1143 * This can't appear below a successful kill_pid(). If it did,
1144 * then the *blank_screen operation could occur while X, having
1145 * received acqsig, is waking up on another processor. This
1146 * condition can lead to overlapping accesses to the VGA range
1147 * and the framebuffer (causing system lockups).
1148 *
1149 * To account for this we duplicate this code below only if the
1150 * controlling process is gone and we've called reset_vc.
1151 */
1152 if (old_vc_mode != vc->vc_mode) {
1153 if (vc->vc_mode == KD_TEXT)
1154 do_unblank_screen(1);
1155 else
1156 do_blank_screen(1);
1157 }
1158
1159 /*
1160 * If this new console is under process control, send it a signal
1161 * telling it that it has acquired. Also check if it has died and
1162 * clean up (similar to logic employed in change_console())
1163 */
1164 if (vc->vt_mode.mode == VT_PROCESS) {
1165 /*
1166 * Send the signal as privileged - kill_pid() will
1167 * tell us if the process has gone or something else
1168 * is awry
1169 */
1170 if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
1171 /*
1172 * The controlling process has died, so we revert back to
1173 * normal operation. In this case, we'll also change back
1174 * to KD_TEXT mode. I'm not sure if this is strictly correct
1175 * but it saves the agony when the X server dies and the screen
1176 * remains blanked due to KD_GRAPHICS! It would be nice to do
1177 * this outside of VT_PROCESS but there is no single process
1178 * to account for and tracking tty count may be undesirable.
1179 */
1180 reset_vc(vc);
1181
1182 if (old_vc_mode != vc->vc_mode) {
1183 if (vc->vc_mode == KD_TEXT)
1184 do_unblank_screen(1);
1185 else
1186 do_blank_screen(1);
1187 }
1188 }
1189 }
1190
1191 /*
1192 * Wake anyone waiting for their VT to activate
1193 */
1194 vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num);
1195 return;
1196}
1197
1198/*
1199 * Performs the front-end of a vt switch
1200 */
1201void change_console(struct vc_data *new_vc)
1202{
1203 struct vc_data *vc;
1204
1205 if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
1206 return;
1207
1208 /*
1209 * If this vt is in process mode, then we need to handshake with
1210 * that process before switching. Essentially, we store where that
1211 * vt wants to switch to and wait for it to tell us when it's done
1212 * (via VT_RELDISP ioctl).
1213 *
1214 * We also check to see if the controlling process still exists.
1215 * If it doesn't, we reset this vt to auto mode and continue.
1216 * This is a cheap way to track process control. The worst thing
1217 * that can happen is: we send a signal to a process, it dies, and
1218 * the switch gets "lost" waiting for a response; hopefully, the
1219 * user will try again, we'll detect the process is gone (unless
1220 * the user waits just the right amount of time :-) and revert the
1221 * vt to auto control.
1222 */
1223 vc = vc_cons[fg_console].d;
1224 if (vc->vt_mode.mode == VT_PROCESS) {
1225 /*
1226 * Send the signal as privileged - kill_pid() will
1227 * tell us if the process has gone or something else
1228 * is awry.
1229 *
1230 * We need to set vt_newvt *before* sending the signal or we
1231 * have a race.
1232 */
1233 vc->vt_newvt = new_vc->vc_num;
1234 if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
1235 /*
1236 * It worked. Mark the vt to switch to and
1237 * return. The process needs to send us a
1238 * VT_RELDISP ioctl to complete the switch.
1239 */
1240 return;
1241 }
1242
1243 /*
1244 * The controlling process has died, so we revert back to
1245 * normal operation. In this case, we'll also change back
1246 * to KD_TEXT mode. I'm not sure if this is strictly correct
1247 * but it saves the agony when the X server dies and the screen
1248 * remains blanked due to KD_GRAPHICS! It would be nice to do
1249 * this outside of VT_PROCESS but there is no single process
1250 * to account for and tracking tty count may be undesirable.
1251 */
1252 reset_vc(vc);
1253
1254 /*
1255 * Fall through to normal (VT_AUTO) handling of the switch...
1256 */
1257 }
1258
1259 /*
1260 * Ignore all switches in KD_GRAPHICS+VT_AUTO mode
1261 */
1262 if (vc->vc_mode == KD_GRAPHICS)
1263 return;
1264
1265 complete_change_console(new_vc);
1266}
1267
1268/* Perform a kernel triggered VT switch for suspend/resume */
1269
1270static int disable_vt_switch;
1271
1272int vt_move_to_console(unsigned int vt, int alloc)
1273{
1274 int prev;
1275
1276 console_lock();
1277 /* Graphics mode - up to X */
1278 if (disable_vt_switch) {
1279 console_unlock();
1280 return 0;
1281 }
1282 prev = fg_console;
1283
1284 if (alloc && vc_allocate(vt)) {
1285 /* we can't have a free VC for now. Too bad,
1286 * we don't want to mess the screen for now. */
1287 console_unlock();
1288 return -ENOSPC;
1289 }
1290
1291 if (set_console(vt)) {
1292 /*
1293 * We're unable to switch to the SUSPEND_CONSOLE.
1294 * Let the calling function know so it can decide
1295 * what to do.
1296 */
1297 console_unlock();
1298 return -EIO;
1299 }
1300 console_unlock();
1301 if (vt_waitactive(vt + 1)) {
1302 pr_debug("Suspend: Can't switch VCs.");
1303 return -EINTR;
1304 }
1305 return prev;
1306}
1307
1308/*
1309 * Normally during a suspend, we allocate a new console and switch to it.
1310 * When we resume, we switch back to the original console. This switch
1311 * can be slow, so on systems where the framebuffer can handle restoration
1312 * of video registers anyways, there's little point in doing the console
1313 * switch. This function allows you to disable it by passing it '0'.
1314 */
1315void pm_set_vt_switch(int do_switch)
1316{
1317 console_lock();
1318 disable_vt_switch = !do_switch;
1319 console_unlock();
1320}
1321EXPORT_SYMBOL(pm_set_vt_switch);