Showing error 799

User: Jiri Slaby
Error type: Memory Leak
Error type description: There the code omits to free some allocated memory
File location: drivers/char/vt_ioctl.c
Line in file: 143
Project: Linux Kernel
Project version: 2.6.28
Tools: Stanse (1.2)
Entered: 2011-11-07 22:26:27 UTC

Source: 

   1/*
   2 *  linux/drivers/char/vt_ioctl.c
   3 *
   4 *  Copyright (C) 1992 obz under the linux copyright
   5 *
   6 *  Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
   7 *  Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
   8 *  Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
   9 *  Some code moved for less code duplication - Andi Kleen - Mar 1997
  10 *  Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
  11 */
  12
  13#include <linux/types.h>
  14#include <linux/errno.h>
  15#include <linux/sched.h>
  16#include <linux/tty.h>
  17#include <linux/timer.h>
  18#include <linux/kernel.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
  38char vt_dont_switch;
  39extern 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
  61static void complete_change_console(struct vc_data *vc);
  62
  63/*
  64 * these are the valid i/o ports we're allowed to change. they map all the
  65 * video ports
  66 */
  67#define GPFIRST 0x3b4
  68#define GPLAST 0x3df
  69#define GPNUM (GPLAST - GPFIRST + 1)
  70
  71#define i (tmp.kb_index)
  72#define s (tmp.kb_table)
  73#define v (tmp.kb_value)
  74static inline int
  75do_kdsk_ioctl(int cmd, struct kbentry __user *user_kbe, int perm, struct kbd_struct *kbd)
  76{
  77        struct kbentry tmp;
  78        ushort *key_map, val, ov;
  79
  80        if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
  81                return -EFAULT;
  82
  83        if (!capable(CAP_SYS_TTY_CONFIG))
  84                perm = 0;
  85
  86        switch (cmd) {
  87        case KDGKBENT:
  88                key_map = key_maps[s];
  89                if (key_map) {
  90                    val = U(key_map[i]);
  91                    if (kbd->kbdmode != VC_UNICODE && KTYP(val) >= NR_TYPES)
  92                        val = K_HOLE;
  93                } else
  94                    val = (i ? K_HOLE : K_NOSUCHMAP);
  95                return put_user(val, &user_kbe->kb_value);
  96        case KDSKBENT:
  97                if (!perm)
  98                        return -EPERM;
  99                if (!i && v == K_NOSUCHMAP) {
 100                        /* deallocate map */
 101                        key_map = key_maps[s];
 102                        if (s && key_map) {
 103                            key_maps[s] = NULL;
 104                            if (key_map[0] == U(K_ALLOCATED)) {
 105                                        kfree(key_map);
 106                                        keymap_count--;
 107                            }
 108                        }
 109                        break;
 110                }
 111
 112                if (KTYP(v) < NR_TYPES) {
 113                    if (KVAL(v) > max_vals[KTYP(v)])
 114                                return -EINVAL;
 115                } else
 116                    if (kbd->kbdmode != VC_UNICODE)
 117                                return -EINVAL;
 118
 119                /* ++Geert: non-PC keyboards may generate keycode zero */
 120#if !defined(__mc68000__) && !defined(__powerpc__)
 121                /* assignment to entry 0 only tests validity of args */
 122                if (!i)
 123                        break;
 124#endif
 125
 126                if (!(key_map = key_maps[s])) {
 127                        int j;
 128
 129                        if (keymap_count >= MAX_NR_OF_USER_KEYMAPS &&
 130                            !capable(CAP_SYS_RESOURCE))
 131                                return -EPERM;
 132
 133                        key_map = kmalloc(sizeof(plain_map),
 134                                                     GFP_KERNEL);
 135                        if (!key_map)
 136                                return -ENOMEM;
 137                        key_maps[s] = key_map;
 138                        key_map[0] = U(K_ALLOCATED);
 139                        for (j = 1; j < NR_KEYS; j++)
 140                                key_map[j] = U(K_HOLE);
 141                        keymap_count++;
 142                }
 143                ov = U(key_map[i]);
 144                if (v == ov)
 145                        break;        /* nothing to do */
 146                /*
 147                 * Attention Key.
 148                 */
 149                if (((ov == K_SAK) || (v == K_SAK)) && !capable(CAP_SYS_ADMIN))
 150                        return -EPERM;
 151                key_map[i] = U(v);
 152                if (!s && (KTYP(ov) == KT_SHIFT || KTYP(v) == KT_SHIFT))
 153                        compute_shiftstate();
 154                break;
 155        }
 156        return 0;
 157}
 158#undef i
 159#undef s
 160#undef v
 161
 162static inline int 
 163do_kbkeycode_ioctl(int cmd, struct kbkeycode __user *user_kbkc, int perm)
 164{
 165        struct kbkeycode tmp;
 166        int kc = 0;
 167
 168        if (copy_from_user(&tmp, user_kbkc, sizeof(struct kbkeycode)))
 169                return -EFAULT;
 170        switch (cmd) {
 171        case KDGETKEYCODE:
 172                kc = getkeycode(tmp.scancode);
 173                if (kc >= 0)
 174                        kc = put_user(kc, &user_kbkc->keycode);
 175                break;
 176        case KDSETKEYCODE:
 177                if (!perm)
 178                        return -EPERM;
 179                kc = setkeycode(tmp.scancode, tmp.keycode);
 180                break;
 181        }
 182        return kc;
 183}
 184
 185static inline int
 186do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
 187{
 188        struct kbsentry *kbs;
 189        char *p;
 190        u_char *q;
 191        u_char __user *up;
 192        int sz;
 193        int delta;
 194        char *first_free, *fj, *fnw;
 195        int i, j, k;
 196        int ret;
 197
 198        if (!capable(CAP_SYS_TTY_CONFIG))
 199                perm = 0;
 200
 201        kbs = kmalloc(sizeof(*kbs), GFP_KERNEL);
 202        if (!kbs) {
 203                ret = -ENOMEM;
 204                goto reterr;
 205        }
 206
 207        /* we mostly copy too much here (512bytes), but who cares ;) */
 208        if (copy_from_user(kbs, user_kdgkb, sizeof(struct kbsentry))) {
 209                ret = -EFAULT;
 210                goto reterr;
 211        }
 212        kbs->kb_string[sizeof(kbs->kb_string)-1] = '\0';
 213        i = kbs->kb_func;
 214
 215        switch (cmd) {
 216        case KDGKBSENT:
 217                sz = sizeof(kbs->kb_string) - 1; /* sz should have been
 218                                                  a struct member */
 219                up = user_kdgkb->kb_string;
 220                p = func_table[i];
 221                if(p)
 222                        for ( ; *p && sz; p++, sz--)
 223                                if (put_user(*p, up++)) {
 224                                        ret = -EFAULT;
 225                                        goto reterr;
 226                                }
 227                if (put_user('\0', up)) {
 228                        ret = -EFAULT;
 229                        goto reterr;
 230                }
 231                kfree(kbs);
 232                return ((p && *p) ? -EOVERFLOW : 0);
 233        case KDSKBSENT:
 234                if (!perm) {
 235                        ret = -EPERM;
 236                        goto reterr;
 237                }
 238
 239                q = func_table[i];
 240                first_free = funcbufptr + (funcbufsize - funcbufleft);
 241                for (j = i+1; j < MAX_NR_FUNC && !func_table[j]; j++) 
 242                        ;
 243                if (j < MAX_NR_FUNC)
 244                        fj = func_table[j];
 245                else
 246                        fj = first_free;
 247
 248                delta = (q ? -strlen(q) : 1) + strlen(kbs->kb_string);
 249                if (delta <= funcbufleft) {         /* it fits in current buf */
 250                    if (j < MAX_NR_FUNC) {
 251                        memmove(fj + delta, fj, first_free - fj);
 252                        for (k = j; k < MAX_NR_FUNC; k++)
 253                            if (func_table[k])
 254                                func_table[k] += delta;
 255                    }
 256                    if (!q)
 257                      func_table[i] = fj;
 258                    funcbufleft -= delta;
 259                } else {                        /* allocate a larger buffer */
 260                    sz = 256;
 261                    while (sz < funcbufsize - funcbufleft + delta)
 262                      sz <<= 1;
 263                    fnw = kmalloc(sz, GFP_KERNEL);
 264                    if(!fnw) {
 265                      ret = -ENOMEM;
 266                      goto reterr;
 267                    }
 268
 269                    if (!q)
 270                      func_table[i] = fj;
 271                    if (fj > funcbufptr)
 272                        memmove(fnw, funcbufptr, fj - funcbufptr);
 273                    for (k = 0; k < j; k++)
 274                      if (func_table[k])
 275                        func_table[k] = fnw + (func_table[k] - funcbufptr);
 276
 277                    if (first_free > fj) {
 278                        memmove(fnw + (fj - funcbufptr) + delta, fj, first_free - fj);
 279                        for (k = j; k < MAX_NR_FUNC; k++)
 280                          if (func_table[k])
 281                            func_table[k] = fnw + (func_table[k] - funcbufptr) + delta;
 282                    }
 283                    if (funcbufptr != func_buf)
 284                      kfree(funcbufptr);
 285                    funcbufptr = fnw;
 286                    funcbufleft = funcbufleft - delta + sz - funcbufsize;
 287                    funcbufsize = sz;
 288                }
 289                strcpy(func_table[i], kbs->kb_string);
 290                break;
 291        }
 292        ret = 0;
 293reterr:
 294        kfree(kbs);
 295        return ret;
 296}
 297
 298static inline int 
 299do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
 300{
 301        struct consolefontdesc cfdarg;
 302        int i;
 303
 304        if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc))) 
 305                return -EFAULT;
 306         
 307        switch (cmd) {
 308        case PIO_FONTX:
 309                if (!perm)
 310                        return -EPERM;
 311                op->op = KD_FONT_OP_SET;
 312                op->flags = KD_FONT_FLAG_OLD;
 313                op->width = 8;
 314                op->height = cfdarg.charheight;
 315                op->charcount = cfdarg.charcount;
 316                op->data = cfdarg.chardata;
 317                return con_font_op(vc_cons[fg_console].d, op);
 318        case GIO_FONTX: {
 319                op->op = KD_FONT_OP_GET;
 320                op->flags = KD_FONT_FLAG_OLD;
 321                op->width = 8;
 322                op->height = cfdarg.charheight;
 323                op->charcount = cfdarg.charcount;
 324                op->data = cfdarg.chardata;
 325                i = con_font_op(vc_cons[fg_console].d, op);
 326                if (i)
 327                        return i;
 328                cfdarg.charheight = op->height;
 329                cfdarg.charcount = op->charcount;
 330                if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
 331                        return -EFAULT;
 332                return 0;
 333                }
 334        }
 335        return -EINVAL;
 336}
 337
 338static inline int 
 339do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
 340{
 341        struct unimapdesc tmp;
 342
 343        if (copy_from_user(&tmp, user_ud, sizeof tmp))
 344                return -EFAULT;
 345        if (tmp.entries)
 346                if (!access_ok(VERIFY_WRITE, tmp.entries,
 347                                tmp.entry_ct*sizeof(struct unipair)))
 348                        return -EFAULT;
 349        switch (cmd) {
 350        case PIO_UNIMAP:
 351                if (!perm)
 352                        return -EPERM;
 353                return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
 354        case GIO_UNIMAP:
 355                if (!perm && fg_console != vc->vc_num)
 356                        return -EPERM;
 357                return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries);
 358        }
 359        return 0;
 360}
 361
 362/*
 363 * We handle the console-specific ioctl's here.  We allow the
 364 * capability to modify any console, not just the fg_console. 
 365 */
 366int vt_ioctl(struct tty_struct *tty, struct file * file,
 367             unsigned int cmd, unsigned long arg)
 368{
 369        struct vc_data *vc = (struct vc_data *)tty->driver_data;
 370        struct console_font_op op;        /* used in multiple places here */
 371        struct kbd_struct * kbd;
 372        unsigned int console;
 373        unsigned char ucval;
 374        void __user *up = (void __user *)arg;
 375        int i, perm;
 376        int ret = 0;
 377
 378        console = vc->vc_num;
 379
 380        lock_kernel();
 381
 382        if (!vc_cons_allocated(console)) {         /* impossible? */
 383                ret = -ENOIOCTLCMD;
 384                goto out;
 385        }
 386
 387
 388        /*
 389         * To have permissions to do most of the vt ioctls, we either have
 390         * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
 391         */
 392        perm = 0;
 393        if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
 394                perm = 1;
 395 
 396        kbd = kbd_table + console;
 397        switch (cmd) {
 398        case TIOCLINUX:
 399                return tioclinux(tty, arg);
 400        case KIOCSOUND:
 401                if (!perm)
 402                        goto eperm;
 403                if (arg)
 404                        arg = CLOCK_TICK_RATE / arg;
 405                kd_mksound(arg, 0);
 406                break;
 407
 408        case KDMKTONE:
 409                if (!perm)
 410                        goto eperm;
 411        {
 412                unsigned int ticks, count;
 413                
 414                /*
 415                 * Generate the tone for the appropriate number of ticks.
 416                 * If the time is zero, turn off sound ourselves.
 417                 */
 418                ticks = HZ * ((arg >> 16) & 0xffff) / 1000;
 419                count = ticks ? (arg & 0xffff) : 0;
 420                if (count)
 421                        count = CLOCK_TICK_RATE / count;
 422                kd_mksound(count, ticks);
 423                break;
 424        }
 425
 426        case KDGKBTYPE:
 427                /*
 428                 * this is naive.
 429                 */
 430                ucval = KB_101;
 431                goto setchar;
 432
 433                /*
 434                 * These cannot be implemented on any machine that implements
 435                 * ioperm() in user level (such as Alpha PCs) or not at all.
 436                 *
 437                 * XXX: you should never use these, just call ioperm directly..
 438                 */
 439#ifdef CONFIG_X86
 440        case KDADDIO:
 441        case KDDELIO:
 442                /*
 443                 * KDADDIO and KDDELIO may be able to add ports beyond what
 444                 * we reject here, but to be safe...
 445                 */
 446                if (arg < GPFIRST || arg > GPLAST) {
 447                        ret = -EINVAL;
 448                        break;
 449                }
 450                ret = sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
 451                break;
 452
 453        case KDENABIO:
 454        case KDDISABIO:
 455                ret = sys_ioperm(GPFIRST, GPNUM,
 456                                  (cmd == KDENABIO)) ? -ENXIO : 0;
 457                break;
 458#endif
 459
 460        /* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
 461                
 462        case KDKBDREP:
 463        {
 464                struct kbd_repeat kbrep;
 465                
 466                if (!capable(CAP_SYS_TTY_CONFIG))
 467                        goto eperm;
 468
 469                if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
 470                        ret =  -EFAULT;
 471                        break;
 472                }
 473                ret = kbd_rate(&kbrep);
 474                if (ret)
 475                        break;
 476                if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
 477                        ret = -EFAULT;
 478                break;
 479        }
 480
 481        case KDSETMODE:
 482                /*
 483                 * currently, setting the mode from KD_TEXT to KD_GRAPHICS
 484                 * doesn't do a whole lot. i'm not sure if it should do any
 485                 * restoration of modes or what...
 486                 *
 487                 * XXX It should at least call into the driver, fbdev's definitely
 488                 * need to restore their engine state. --BenH
 489                 */
 490                if (!perm)
 491                        goto eperm;
 492                switch (arg) {
 493                case KD_GRAPHICS:
 494                        break;
 495                case KD_TEXT0:
 496                case KD_TEXT1:
 497                        arg = KD_TEXT;
 498                case KD_TEXT:
 499                        break;
 500                default:
 501                        ret = -EINVAL;
 502                        goto out;
 503                }
 504                if (vc->vc_mode == (unsigned char) arg)
 505                        break;
 506                vc->vc_mode = (unsigned char) arg;
 507                if (console != fg_console)
 508                        break;
 509                /*
 510                 * explicitly blank/unblank the screen if switching modes
 511                 */
 512                acquire_console_sem();
 513                if (arg == KD_TEXT)
 514                        do_unblank_screen(1);
 515                else
 516                        do_blank_screen(1);
 517                release_console_sem();
 518                break;
 519
 520        case KDGETMODE:
 521                ucval = vc->vc_mode;
 522                goto setint;
 523
 524        case KDMAPDISP:
 525        case KDUNMAPDISP:
 526                /*
 527                 * these work like a combination of mmap and KDENABIO.
 528                 * this could be easily finished.
 529                 */
 530                ret = -EINVAL;
 531                break;
 532
 533        case KDSKBMODE:
 534                if (!perm)
 535                        goto eperm;
 536                switch(arg) {
 537                  case K_RAW:
 538                        kbd->kbdmode = VC_RAW;
 539                        break;
 540                  case K_MEDIUMRAW:
 541                        kbd->kbdmode = VC_MEDIUMRAW;
 542                        break;
 543                  case K_XLATE:
 544                        kbd->kbdmode = VC_XLATE;
 545                        compute_shiftstate();
 546                        break;
 547                  case K_UNICODE:
 548                        kbd->kbdmode = VC_UNICODE;
 549                        compute_shiftstate();
 550                        break;
 551                  default:
 552                        ret = -EINVAL;
 553                        goto out;
 554                }
 555                tty_ldisc_flush(tty);
 556                break;
 557
 558        case KDGKBMODE:
 559                ucval = ((kbd->kbdmode == VC_RAW) ? K_RAW :
 560                                 (kbd->kbdmode == VC_MEDIUMRAW) ? K_MEDIUMRAW :
 561                                 (kbd->kbdmode == VC_UNICODE) ? K_UNICODE :
 562                                 K_XLATE);
 563                goto setint;
 564
 565        /* this could be folded into KDSKBMODE, but for compatibility
 566           reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
 567        case KDSKBMETA:
 568                switch(arg) {
 569                  case K_METABIT:
 570                        clr_vc_kbd_mode(kbd, VC_META);
 571                        break;
 572                  case K_ESCPREFIX:
 573                        set_vc_kbd_mode(kbd, VC_META);
 574                        break;
 575                  default:
 576                        ret = -EINVAL;
 577                }
 578                break;
 579
 580        case KDGKBMETA:
 581                ucval = (vc_kbd_mode(kbd, VC_META) ? K_ESCPREFIX : K_METABIT);
 582        setint:
 583                ret = put_user(ucval, (int __user *)arg);
 584                break;
 585
 586        case KDGETKEYCODE:
 587        case KDSETKEYCODE:
 588                if(!capable(CAP_SYS_TTY_CONFIG))
 589                        perm = 0;
 590                ret = do_kbkeycode_ioctl(cmd, up, perm);
 591                break;
 592
 593        case KDGKBENT:
 594        case KDSKBENT:
 595                ret = do_kdsk_ioctl(cmd, up, perm, kbd);
 596                break;
 597
 598        case KDGKBSENT:
 599        case KDSKBSENT:
 600                ret = do_kdgkb_ioctl(cmd, up, perm);
 601                break;
 602
 603        case KDGKBDIACR:
 604        {
 605                struct kbdiacrs __user *a = up;
 606                struct kbdiacr diacr;
 607                int i;
 608
 609                if (put_user(accent_table_size, &a->kb_cnt)) {
 610                        ret = -EFAULT;
 611                        break;
 612                }
 613                for (i = 0; i < accent_table_size; i++) {
 614                        diacr.diacr = conv_uni_to_8bit(accent_table[i].diacr);
 615                        diacr.base = conv_uni_to_8bit(accent_table[i].base);
 616                        diacr.result = conv_uni_to_8bit(accent_table[i].result);
 617                        if (copy_to_user(a->kbdiacr + i, &diacr, sizeof(struct kbdiacr))) {
 618                                ret = -EFAULT;
 619                                break;
 620                        }
 621                }
 622                break;
 623        }
 624        case KDGKBDIACRUC:
 625        {
 626                struct kbdiacrsuc __user *a = up;
 627
 628                if (put_user(accent_table_size, &a->kb_cnt))
 629                        ret = -EFAULT;
 630                else if (copy_to_user(a->kbdiacruc, accent_table,
 631                                accent_table_size*sizeof(struct kbdiacruc)))
 632                        ret = -EFAULT;
 633                break;
 634        }
 635
 636        case KDSKBDIACR:
 637        {
 638                struct kbdiacrs __user *a = up;
 639                struct kbdiacr diacr;
 640                unsigned int ct;
 641                int i;
 642
 643                if (!perm)
 644                        goto eperm;
 645                if (get_user(ct,&a->kb_cnt)) {
 646                        ret = -EFAULT;
 647                        break;
 648                }
 649                if (ct >= MAX_DIACR) {
 650                        ret = -EINVAL;
 651                        break;
 652                }
 653                accent_table_size = ct;
 654                for (i = 0; i < ct; i++) {
 655                        if (copy_from_user(&diacr, a->kbdiacr + i, sizeof(struct kbdiacr))) {
 656                                ret = -EFAULT;
 657                                break;
 658                        }
 659                        accent_table[i].diacr = conv_8bit_to_uni(diacr.diacr);
 660                        accent_table[i].base = conv_8bit_to_uni(diacr.base);
 661                        accent_table[i].result = conv_8bit_to_uni(diacr.result);
 662                }
 663                break;
 664        }
 665
 666        case KDSKBDIACRUC:
 667        {
 668                struct kbdiacrsuc __user *a = up;
 669                unsigned int ct;
 670
 671                if (!perm)
 672                        goto eperm;
 673                if (get_user(ct,&a->kb_cnt)) {
 674                        ret = -EFAULT;
 675                        break;
 676                }
 677                if (ct >= MAX_DIACR) {
 678                        ret = -EINVAL;
 679                        break;
 680                }
 681                accent_table_size = ct;
 682                if (copy_from_user(accent_table, a->kbdiacruc, ct*sizeof(struct kbdiacruc)))
 683                        ret = -EFAULT;
 684                break;
 685        }
 686
 687        /* the ioctls below read/set the flags usually shown in the leds */
 688        /* don't use them - they will go away without warning */
 689        case KDGKBLED:
 690                ucval = kbd->ledflagstate | (kbd->default_ledflagstate << 4);
 691                goto setchar;
 692
 693        case KDSKBLED:
 694                if (!perm)
 695                        goto eperm;
 696                if (arg & ~0x77) {
 697                        ret = -EINVAL;
 698                        break;
 699                }
 700                kbd->ledflagstate = (arg & 7);
 701                kbd->default_ledflagstate = ((arg >> 4) & 7);
 702                set_leds();
 703                break;
 704
 705        /* the ioctls below only set the lights, not the functions */
 706        /* for those, see KDGKBLED and KDSKBLED above */
 707        case KDGETLED:
 708                ucval = getledstate();
 709        setchar:
 710                ret = put_user(ucval, (char __user *)arg);
 711                break;
 712
 713        case KDSETLED:
 714                if (!perm)
 715                        goto eperm;
 716                setledstate(kbd, arg);
 717                break;
 718
 719        /*
 720         * A process can indicate its willingness to accept signals
 721         * generated by pressing an appropriate key combination.
 722         * Thus, one can have a daemon that e.g. spawns a new console
 723         * upon a keypress and then changes to it.
 724         * See also the kbrequest field of inittab(5).
 725         */
 726        case KDSIGACCEPT:
 727        {
 728                if (!perm || !capable(CAP_KILL))
 729                        goto eperm;
 730                if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
 731                        ret = -EINVAL;
 732                else {
 733                        spin_lock_irq(&vt_spawn_con.lock);
 734                        put_pid(vt_spawn_con.pid);
 735                        vt_spawn_con.pid = get_pid(task_pid(current));
 736                        vt_spawn_con.sig = arg;
 737                        spin_unlock_irq(&vt_spawn_con.lock);
 738                }
 739                break;
 740        }
 741
 742        case VT_SETMODE:
 743        {
 744                struct vt_mode tmp;
 745
 746                if (!perm)
 747                        goto eperm;
 748                if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
 749                        ret = -EFAULT;
 750                        goto out;
 751                }
 752                if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
 753                        ret = -EINVAL;
 754                        goto out;
 755                }
 756                acquire_console_sem();
 757                vc->vt_mode = tmp;
 758                /* the frsig is ignored, so we set it to 0 */
 759                vc->vt_mode.frsig = 0;
 760                put_pid(vc->vt_pid);
 761                vc->vt_pid = get_pid(task_pid(current));
 762                /* no switch is required -- saw@shade.msu.ru */
 763                vc->vt_newvt = -1;
 764                release_console_sem();
 765                break;
 766        }
 767
 768        case VT_GETMODE:
 769        {
 770                struct vt_mode tmp;
 771                int rc;
 772
 773                acquire_console_sem();
 774                memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
 775                release_console_sem();
 776
 777                rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
 778                if (rc)
 779                        ret = -EFAULT;
 780                break;
 781        }
 782
 783        /*
 784         * Returns global vt state. Note that VT 0 is always open, since
 785         * it's an alias for the current VT, and people can't use it here.
 786         * We cannot return state for more than 16 VTs, since v_state is short.
 787         */
 788        case VT_GETSTATE:
 789        {
 790                struct vt_stat __user *vtstat = up;
 791                unsigned short state, mask;
 792
 793                if (put_user(fg_console + 1, &vtstat->v_active))
 794                        ret = -EFAULT;
 795                else {
 796                        state = 1;        /* /dev/tty0 is always open */
 797                        for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
 798                                                        ++i, mask <<= 1)
 799                                if (VT_IS_IN_USE(i))
 800                                        state |= mask;
 801                        ret = put_user(state, &vtstat->v_state);
 802                }
 803                break;
 804        }
 805
 806        /*
 807         * Returns the first available (non-opened) console.
 808         */
 809        case VT_OPENQRY:
 810                for (i = 0; i < MAX_NR_CONSOLES; ++i)
 811                        if (! VT_IS_IN_USE(i))
 812                                break;
 813                ucval = i < MAX_NR_CONSOLES ? (i+1) : -1;
 814                goto setint;                 
 815
 816        /*
 817         * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
 818         * with num >= 1 (switches to vt 0, our console, are not allowed, just
 819         * to preserve sanity).
 820         */
 821        case VT_ACTIVATE:
 822                if (!perm)
 823                        goto eperm;
 824                if (arg == 0 || arg > MAX_NR_CONSOLES)
 825                        ret =  -ENXIO;
 826                else {
 827                        arg--;
 828                        acquire_console_sem();
 829                        ret = vc_allocate(arg);
 830                        release_console_sem();
 831                        if (ret)
 832                                break;
 833                        set_console(arg);
 834                }
 835                break;
 836
 837        /*
 838         * wait until the specified VT has been activated
 839         */
 840        case VT_WAITACTIVE:
 841                if (!perm)
 842                        goto eperm;
 843                if (arg == 0 || arg > MAX_NR_CONSOLES)
 844                        ret = -ENXIO;
 845                else
 846                        ret = vt_waitactive(arg - 1);
 847                break;
 848
 849        /*
 850         * If a vt is under process control, the kernel will not switch to it
 851         * immediately, but postpone the operation until the process calls this
 852         * ioctl, allowing the switch to complete.
 853         *
 854         * According to the X sources this is the behavior:
 855         *        0:        pending switch-from not OK
 856         *        1:        pending switch-from OK
 857         *        2:        completed switch-to OK
 858         */
 859        case VT_RELDISP:
 860                if (!perm)
 861                        goto eperm;
 862
 863                if (vc->vt_mode.mode != VT_PROCESS) {
 864                        ret = -EINVAL;
 865                        break;
 866                }
 867                /*
 868                 * Switching-from response
 869                 */
 870                acquire_console_sem();
 871                if (vc->vt_newvt >= 0) {
 872                        if (arg == 0)
 873                                /*
 874                                 * Switch disallowed, so forget we were trying
 875                                 * to do it.
 876                                 */
 877                                vc->vt_newvt = -1;
 878
 879                        else {
 880                                /*
 881                                 * The current vt has been released, so
 882                                 * complete the switch.
 883                                 */
 884                                int newvt;
 885                                newvt = vc->vt_newvt;
 886                                vc->vt_newvt = -1;
 887                                ret = vc_allocate(newvt);
 888                                if (ret) {
 889                                        release_console_sem();
 890                                        break;
 891                                }
 892                                /*
 893                                 * When we actually do the console switch,
 894                                 * make sure we are atomic with respect to
 895                                 * other console switches..
 896                                 */
 897                                complete_change_console(vc_cons[newvt].d);
 898                        }
 899                } else {
 900                        /*
 901                         * Switched-to response
 902                         */
 903                        /*
 904                         * If it's just an ACK, ignore it
 905                         */
 906                        if (arg != VT_ACKACQ)
 907                                ret = -EINVAL;
 908                }
 909                release_console_sem();
 910                break;
 911
 912         /*
 913          * Disallocate memory associated to VT (but leave VT1)
 914          */
 915         case VT_DISALLOCATE:
 916                if (arg > MAX_NR_CONSOLES) {
 917                        ret = -ENXIO;
 918                        break;
 919                }
 920                if (arg == 0) {
 921                    /* deallocate all unused consoles, but leave 0 */
 922                        acquire_console_sem();
 923                        for (i=1; i<MAX_NR_CONSOLES; i++)
 924                                if (! VT_BUSY(i))
 925                                        vc_deallocate(i);
 926                        release_console_sem();
 927                } else {
 928                        /* deallocate a single console, if possible */
 929                        arg--;
 930                        if (VT_BUSY(arg))
 931                                ret = -EBUSY;
 932                        else if (arg) {                              /* leave 0 */
 933                                acquire_console_sem();
 934                                vc_deallocate(arg);
 935                                release_console_sem();
 936                        }
 937                }
 938                break;
 939
 940        case VT_RESIZE:
 941        {
 942                struct vt_sizes __user *vtsizes = up;
 943                struct vc_data *vc;
 944
 945                ushort ll,cc;
 946                if (!perm)
 947                        goto eperm;
 948                if (get_user(ll, &vtsizes->v_rows) ||
 949                    get_user(cc, &vtsizes->v_cols))
 950                        ret = -EFAULT;
 951                else {
 952                        acquire_console_sem();
 953                        for (i = 0; i < MAX_NR_CONSOLES; i++) {
 954                                vc = vc_cons[i].d;
 955
 956                                if (vc) {
 957                                        vc->vc_resize_user = 1;
 958                                        vc_resize(vc_cons[i].d, cc, ll);
 959                                }
 960                        }
 961                        release_console_sem();
 962                }
 963                break;
 964        }
 965
 966        case VT_RESIZEX:
 967        {
 968                struct vt_consize __user *vtconsize = up;
 969                ushort ll,cc,vlin,clin,vcol,ccol;
 970                if (!perm)
 971                        goto eperm;
 972                if (!access_ok(VERIFY_READ, vtconsize,
 973                                sizeof(struct vt_consize))) {
 974                        ret = -EFAULT;
 975                        break;
 976                }
 977                /* FIXME: Should check the copies properly */
 978                __get_user(ll, &vtconsize->v_rows);
 979                __get_user(cc, &vtconsize->v_cols);
 980                __get_user(vlin, &vtconsize->v_vlin);
 981                __get_user(clin, &vtconsize->v_clin);
 982                __get_user(vcol, &vtconsize->v_vcol);
 983                __get_user(ccol, &vtconsize->v_ccol);
 984                vlin = vlin ? vlin : vc->vc_scan_lines;
 985                if (clin) {
 986                        if (ll) {
 987                                if (ll != vlin/clin) {
 988                                        /* Parameters don't add up */
 989                                        ret = -EINVAL;
 990                                        break;
 991                                }
 992                        } else 
 993                                ll = vlin/clin;
 994                }
 995                if (vcol && ccol) {
 996                        if (cc) {
 997                                if (cc != vcol/ccol) {
 998                                        ret = -EINVAL;
 999                                        break;
1000                                }
1001                        } else
1002                                cc = vcol/ccol;
1003                }
1004
1005                if (clin > 32) {
1006                        ret =  -EINVAL;
1007                        break;
1008                }
1009                    
1010                for (i = 0; i < MAX_NR_CONSOLES; i++) {
1011                        if (!vc_cons[i].d)
1012                                continue;
1013                        acquire_console_sem();
1014                        if (vlin)
1015                                vc_cons[i].d->vc_scan_lines = vlin;
1016                        if (clin)
1017                                vc_cons[i].d->vc_font.height = clin;
1018                        vc_cons[i].d->vc_resize_user = 1;
1019                        vc_resize(vc_cons[i].d, cc, ll);
1020                        release_console_sem();
1021                }
1022                break;
1023        }
1024
1025        case PIO_FONT: {
1026                if (!perm)
1027                        goto eperm;
1028                op.op = KD_FONT_OP_SET;
1029                op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC;        /* Compatibility */
1030                op.width = 8;
1031                op.height = 0;
1032                op.charcount = 256;
1033                op.data = up;
1034                ret = con_font_op(vc_cons[fg_console].d, &op);
1035                break;
1036        }
1037
1038        case GIO_FONT: {
1039                op.op = KD_FONT_OP_GET;
1040                op.flags = KD_FONT_FLAG_OLD;
1041                op.width = 8;
1042                op.height = 32;
1043                op.charcount = 256;
1044                op.data = up;
1045                ret = con_font_op(vc_cons[fg_console].d, &op);
1046                break;
1047        }
1048
1049        case PIO_CMAP:
1050                if (!perm)
1051                        ret = -EPERM;
1052                else
1053                        ret = con_set_cmap(up);
1054                break;
1055
1056        case GIO_CMAP:
1057                ret = con_get_cmap(up);
1058                break;
1059
1060        case PIO_FONTX:
1061        case GIO_FONTX:
1062                ret = do_fontx_ioctl(cmd, up, perm, &op);
1063                break;
1064
1065        case PIO_FONTRESET:
1066        {
1067                if (!perm)
1068                        goto eperm;
1069
1070#ifdef BROKEN_GRAPHICS_PROGRAMS
1071                /* With BROKEN_GRAPHICS_PROGRAMS defined, the default
1072                   font is not saved. */
1073                ret = -ENOSYS;
1074                break;
1075#else
1076                {
1077                op.op = KD_FONT_OP_SET_DEFAULT;
1078                op.data = NULL;
1079                ret = con_font_op(vc_cons[fg_console].d, &op);
1080                if (ret)
1081                        break;
1082                con_set_default_unimap(vc_cons[fg_console].d);
1083                break;
1084                }
1085#endif
1086        }
1087
1088        case KDFONTOP: {
1089                if (copy_from_user(&op, up, sizeof(op))) {
1090                        ret = -EFAULT;
1091                        break;
1092                }
1093                if (!perm && op.op != KD_FONT_OP_GET)
1094                        goto eperm;
1095                ret = con_font_op(vc, &op);
1096                if (ret)
1097                        break;
1098                if (copy_to_user(up, &op, sizeof(op)))
1099                        ret = -EFAULT;
1100                break;
1101        }
1102
1103        case PIO_SCRNMAP:
1104                if (!perm)
1105                        ret = -EPERM;
1106                else
1107                        ret = con_set_trans_old(up);
1108                break;
1109
1110        case GIO_SCRNMAP:
1111                ret = con_get_trans_old(up);
1112                break;
1113
1114        case PIO_UNISCRNMAP:
1115                if (!perm)
1116                        ret = -EPERM;
1117                else
1118                        ret = con_set_trans_new(up);
1119                break;
1120
1121        case GIO_UNISCRNMAP:
1122                ret = con_get_trans_new(up);
1123                break;
1124
1125        case PIO_UNIMAPCLR:
1126              { struct unimapinit ui;
1127                if (!perm)
1128                        goto eperm;
1129                ret = copy_from_user(&ui, up, sizeof(struct unimapinit));
1130                if (!ret)
1131                        con_clear_unimap(vc, &ui);
1132                break;
1133              }
1134
1135        case PIO_UNIMAP:
1136        case GIO_UNIMAP:
1137                ret = do_unimap_ioctl(cmd, up, perm, vc);
1138                break;
1139
1140        case VT_LOCKSWITCH:
1141                if (!capable(CAP_SYS_TTY_CONFIG))
1142                        goto eperm;
1143                vt_dont_switch = 1;
1144                break;
1145        case VT_UNLOCKSWITCH:
1146                if (!capable(CAP_SYS_TTY_CONFIG))
1147                        goto eperm;
1148                vt_dont_switch = 0;
1149                break;
1150        case VT_GETHIFONTMASK:
1151                ret = put_user(vc->vc_hi_font_mask,
1152                                        (unsigned short __user *)arg);
1153                break;
1154        default:
1155                ret = -ENOIOCTLCMD;
1156        }
1157out:
1158        unlock_kernel();
1159        return ret;
1160eperm:
1161        ret = -EPERM;
1162        goto out;
1163}
1164
1165/*
1166 * Sometimes we want to wait until a particular VT has been activated. We
1167 * do it in a very simple manner. Everybody waits on a single queue and
1168 * get woken up at once. Those that are satisfied go on with their business,
1169 * while those not ready go back to sleep. Seems overkill to add a wait
1170 * to each vt just for this - usually this does nothing!
1171 */
1172static DECLARE_WAIT_QUEUE_HEAD(vt_activate_queue);
1173
1174/*
1175 * Sleeps until a vt is activated, or the task is interrupted. Returns
1176 * 0 if activation, -EINTR if interrupted by a signal handler.
1177 */
1178int vt_waitactive(int vt)
1179{
1180        int retval;
1181        DECLARE_WAITQUEUE(wait, current);
1182
1183        add_wait_queue(&vt_activate_queue, &wait);
1184        for (;;) {
1185                retval = 0;
1186
1187                /*
1188                 * Synchronize with redraw_screen(). By acquiring the console
1189                 * semaphore we make sure that the console switch is completed
1190                 * before we return. If we didn't wait for the semaphore, we
1191                 * could return at a point where fg_console has already been
1192                 * updated, but the console switch hasn't been completed.
1193                 */
1194                acquire_console_sem();
1195                set_current_state(TASK_INTERRUPTIBLE);
1196                if (vt == fg_console) {
1197                        release_console_sem();
1198                        break;
1199                }
1200                release_console_sem();
1201                retval = -ERESTARTNOHAND;
1202                if (signal_pending(current))
1203                        break;
1204                schedule();
1205        }
1206        remove_wait_queue(&vt_activate_queue, &wait);
1207        __set_current_state(TASK_RUNNING);
1208        return retval;
1209}
1210
1211#define vt_wake_waitactive() wake_up(&vt_activate_queue)
1212
1213void reset_vc(struct vc_data *vc)
1214{
1215        vc->vc_mode = KD_TEXT;
1216        kbd_table[vc->vc_num].kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE;
1217        vc->vt_mode.mode = VT_AUTO;
1218        vc->vt_mode.waitv = 0;
1219        vc->vt_mode.relsig = 0;
1220        vc->vt_mode.acqsig = 0;
1221        vc->vt_mode.frsig = 0;
1222        put_pid(vc->vt_pid);
1223        vc->vt_pid = NULL;
1224        vc->vt_newvt = -1;
1225        if (!in_interrupt())    /* Via keyboard.c:SAK() - akpm */
1226                reset_palette(vc);
1227}
1228
1229void vc_SAK(struct work_struct *work)
1230{
1231        struct vc *vc_con =
1232                container_of(work, struct vc, SAK_work);
1233        struct vc_data *vc;
1234        struct tty_struct *tty;
1235
1236        acquire_console_sem();
1237        vc = vc_con->d;
1238        if (vc) {
1239                tty = vc->vc_tty;
1240                /*
1241                 * SAK should also work in all raw modes and reset
1242                 * them properly.
1243                 */
1244                if (tty)
1245                        __do_SAK(tty);
1246                reset_vc(vc);
1247        }
1248        release_console_sem();
1249}
1250
1251/*
1252 * Performs the back end of a vt switch
1253 */
1254static void complete_change_console(struct vc_data *vc)
1255{
1256        unsigned char old_vc_mode;
1257
1258        last_console = fg_console;
1259
1260        /*
1261         * If we're switching, we could be going from KD_GRAPHICS to
1262         * KD_TEXT mode or vice versa, which means we need to blank or
1263         * unblank the screen later.
1264         */
1265        old_vc_mode = vc_cons[fg_console].d->vc_mode;
1266        switch_screen(vc);
1267
1268        /*
1269         * This can't appear below a successful kill_pid().  If it did,
1270         * then the *blank_screen operation could occur while X, having
1271         * received acqsig, is waking up on another processor.  This
1272         * condition can lead to overlapping accesses to the VGA range
1273         * and the framebuffer (causing system lockups).
1274         *
1275         * To account for this we duplicate this code below only if the
1276         * controlling process is gone and we've called reset_vc.
1277         */
1278        if (old_vc_mode != vc->vc_mode) {
1279                if (vc->vc_mode == KD_TEXT)
1280                        do_unblank_screen(1);
1281                else
1282                        do_blank_screen(1);
1283        }
1284
1285        /*
1286         * If this new console is under process control, send it a signal
1287         * telling it that it has acquired. Also check if it has died and
1288         * clean up (similar to logic employed in change_console())
1289         */
1290        if (vc->vt_mode.mode == VT_PROCESS) {
1291                /*
1292                 * Send the signal as privileged - kill_pid() will
1293                 * tell us if the process has gone or something else
1294                 * is awry
1295                 */
1296                if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
1297                /*
1298                 * The controlling process has died, so we revert back to
1299                 * normal operation. In this case, we'll also change back
1300                 * to KD_TEXT mode. I'm not sure if this is strictly correct
1301                 * but it saves the agony when the X server dies and the screen
1302                 * remains blanked due to KD_GRAPHICS! It would be nice to do
1303                 * this outside of VT_PROCESS but there is no single process
1304                 * to account for and tracking tty count may be undesirable.
1305                 */
1306                        reset_vc(vc);
1307
1308                        if (old_vc_mode != vc->vc_mode) {
1309                                if (vc->vc_mode == KD_TEXT)
1310                                        do_unblank_screen(1);
1311                                else
1312                                        do_blank_screen(1);
1313                        }
1314                }
1315        }
1316
1317        /*
1318         * Wake anyone waiting for their VT to activate
1319         */
1320        vt_wake_waitactive();
1321        return;
1322}
1323
1324/*
1325 * Performs the front-end of a vt switch
1326 */
1327void change_console(struct vc_data *new_vc)
1328{
1329        struct vc_data *vc;
1330
1331        if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
1332                return;
1333
1334        /*
1335         * If this vt is in process mode, then we need to handshake with
1336         * that process before switching. Essentially, we store where that
1337         * vt wants to switch to and wait for it to tell us when it's done
1338         * (via VT_RELDISP ioctl).
1339         *
1340         * We also check to see if the controlling process still exists.
1341         * If it doesn't, we reset this vt to auto mode and continue.
1342         * This is a cheap way to track process control. The worst thing
1343         * that can happen is: we send a signal to a process, it dies, and
1344         * the switch gets "lost" waiting for a response; hopefully, the
1345         * user will try again, we'll detect the process is gone (unless
1346         * the user waits just the right amount of time :-) and revert the
1347         * vt to auto control.
1348         */
1349        vc = vc_cons[fg_console].d;
1350        if (vc->vt_mode.mode == VT_PROCESS) {
1351                /*
1352                 * Send the signal as privileged - kill_pid() will
1353                 * tell us if the process has gone or something else
1354                 * is awry.
1355                 *
1356                 * We need to set vt_newvt *before* sending the signal or we
1357                 * have a race.
1358                 */
1359                vc->vt_newvt = new_vc->vc_num;
1360                if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
1361                        /*
1362                         * It worked. Mark the vt to switch to and
1363                         * return. The process needs to send us a
1364                         * VT_RELDISP ioctl to complete the switch.
1365                         */
1366                        return;
1367                }
1368
1369                /*
1370                 * The controlling process has died, so we revert back to
1371                 * normal operation. In this case, we'll also change back
1372                 * to KD_TEXT mode. I'm not sure if this is strictly correct
1373                 * but it saves the agony when the X server dies and the screen
1374                 * remains blanked due to KD_GRAPHICS! It would be nice to do
1375                 * this outside of VT_PROCESS but there is no single process
1376                 * to account for and tracking tty count may be undesirable.
1377                 */
1378                reset_vc(vc);
1379
1380                /*
1381                 * Fall through to normal (VT_AUTO) handling of the switch...
1382                 */
1383        }
1384
1385        /*
1386         * Ignore all switches in KD_GRAPHICS+VT_AUTO mode
1387         */
1388        if (vc->vc_mode == KD_GRAPHICS)
1389                return;
1390
1391        complete_change_console(new_vc);
1392}
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