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linux/drivers/char/vt_ioctl.c
Jiri Slaby a09efb07b5 Char: vt_ioctl, fix BKL imbalance 
Stanse found (again) a BKL imbalance in vt_ioctl.

It's easily triggerable by ioctl(dev_tty_fd, VT_SETACTIVATE, NULL);

Introduced by

commit d3b5cffcf8                                 Author: Alan Cox <alan@linux.intel.com>
Date:   Sat Sep 19 13:13:26 2009 -0700

    vt: add an activate and lock

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:12 -07:00

1783 lines
40 KiB
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Raw Blame History

/*
* linux/drivers/char/vt_ioctl.c
*
* Copyright (C) 1992 obz under the linux copyright
*
* Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
* Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
* Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
* Some code moved for less code duplication - Andi Kleen - Mar 1997
* Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/timer.h>
#include <linux/kernel.h>
#include <linux/compat.h>
#include <linux/module.h>
#include <linux/kd.h>
#include <linux/vt.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/major.h>
#include <linux/fs.h>
#include <linux/console.h>
#include <linux/consolemap.h>
#include <linux/signal.h>
#include <linux/smp_lock.h>
#include <linux/timex.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/kbd_kern.h>
#include <linux/vt_kern.h>
#include <linux/kbd_diacr.h>
#include <linux/selection.h>
char vt_dont_switch;
extern struct tty_driver *console_driver;
#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
/*
* Console (vt and kd) routines, as defined by USL SVR4 manual, and by
* experimentation and study of X386 SYSV handling.
*
* One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
* /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
* and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
* always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
* ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
* /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
* to the current console is done by the main ioctl code.
*/
#ifdef CONFIG_X86
#include <linux/syscalls.h>
#endif
static void complete_change_console(struct vc_data *vc);
/*
* User space VT_EVENT handlers
*/
struct vt_event_wait {
struct list_head list;
struct vt_event event;
int done;
};
static LIST_HEAD(vt_events);
static DEFINE_SPINLOCK(vt_event_lock);
static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue);
/**
* vt_event_post
* @event: the event that occurred
* @old: old console
* @new: new console
*
* Post an VT event to interested VT handlers
*/
void vt_event_post(unsigned int event, unsigned int old, unsigned int new)
{
struct list_head *pos, *head;
unsigned long flags;
int wake = 0;
spin_lock_irqsave(&vt_event_lock, flags);
head = &vt_events;
list_for_each(pos, head) {
struct vt_event_wait *ve = list_entry(pos,
struct vt_event_wait, list);
if (!(ve->event.event & event))
continue;
ve->event.event = event;
/* kernel view is consoles 0..n-1, user space view is
console 1..n with 0 meaning current, so we must bias */
ve->event.old = old + 1;
ve->event.new = new + 1;
wake = 1;
ve->done = 1;
}
spin_unlock_irqrestore(&vt_event_lock, flags);
if (wake)
wake_up_interruptible(&vt_event_waitqueue);
}
/**
* vt_event_wait - wait for an event
* @vw: our event
*
* Waits for an event to occur which completes our vt_event_wait
* structure. On return the structure has wv->done set to 1 for success
* or 0 if some event such as a signal ended the wait.
*/
static void vt_event_wait(struct vt_event_wait *vw)
{
unsigned long flags;
/* Prepare the event */
INIT_LIST_HEAD(&vw->list);
vw->done = 0;
/* Queue our event */
spin_lock_irqsave(&vt_event_lock, flags);
list_add(&vw->list, &vt_events);
spin_unlock_irqrestore(&vt_event_lock, flags);
/* Wait for it to pass */
wait_event_interruptible(vt_event_waitqueue, vw->done);
/* Dequeue it */
spin_lock_irqsave(&vt_event_lock, flags);
list_del(&vw->list);
spin_unlock_irqrestore(&vt_event_lock, flags);
}
/**
* vt_event_wait_ioctl - event ioctl handler
* @arg: argument to ioctl
*
* Implement the VT_WAITEVENT ioctl using the VT event interface
*/
static int vt_event_wait_ioctl(struct vt_event __user *event)
{
struct vt_event_wait vw;
if (copy_from_user(&vw.event, event, sizeof(struct vt_event)))
return -EFAULT;
/* Highest supported event for now */
if (vw.event.event & ~VT_MAX_EVENT)
return -EINVAL;
vt_event_wait(&vw);
/* If it occurred report it */
if (vw.done) {
if (copy_to_user(event, &vw.event, sizeof(struct vt_event)))
return -EFAULT;
return 0;
}
return -EINTR;
}
/**
* vt_waitactive - active console wait
* @event: event code
* @n: new console
*
* Helper for event waits. Used to implement the legacy
* event waiting ioctls in terms of events
*/
int vt_waitactive(int n)
{
struct vt_event_wait vw;
do {
if (n == fg_console + 1)
break;
vw.event.event = VT_EVENT_SWITCH;
vt_event_wait(&vw);
if (vw.done == 0)
return -EINTR;
} while (vw.event.new != n);
return 0;
}
/*
* these are the valid i/o ports we're allowed to change. they map all the
* video ports
*/
#define GPFIRST 0x3b4
#define GPLAST 0x3df
#define GPNUM (GPLAST - GPFIRST + 1)
#define i (tmp.kb_index)
#define s (tmp.kb_table)
#define v (tmp.kb_value)
static inline int
do_kdsk_ioctl(int cmd, struct kbentry __user *user_kbe, int perm, struct kbd_struct *kbd)
{
struct kbentry tmp;
ushort *key_map, val, ov;
if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
return -EFAULT;
if (!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
switch (cmd) {
case KDGKBENT:
key_map = key_maps[s];
if (key_map) {
val = U(key_map[i]);
if (kbd->kbdmode != VC_UNICODE && KTYP(val) >= NR_TYPES)
val = K_HOLE;
} else
val = (i ? K_HOLE : K_NOSUCHMAP);
return put_user(val, &user_kbe->kb_value);
case KDSKBENT:
if (!perm)
return -EPERM;
if (!i && v == K_NOSUCHMAP) {
/* deallocate map */
key_map = key_maps[s];
if (s && key_map) {
key_maps[s] = NULL;
if (key_map[0] == U(K_ALLOCATED)) {
kfree(key_map);
keymap_count--;
}
}
break;
}
if (KTYP(v) < NR_TYPES) {
if (KVAL(v) > max_vals[KTYP(v)])
return -EINVAL;
} else
if (kbd->kbdmode != VC_UNICODE)
return -EINVAL;
/* ++Geert: non-PC keyboards may generate keycode zero */
#if !defined(__mc68000__) && !defined(__powerpc__)
/* assignment to entry 0 only tests validity of args */
if (!i)
break;
#endif
if (!(key_map = key_maps[s])) {
int j;
if (keymap_count >= MAX_NR_OF_USER_KEYMAPS &&
!capable(CAP_SYS_RESOURCE))
return -EPERM;
key_map = kmalloc(sizeof(plain_map),
GFP_KERNEL);
if (!key_map)
return -ENOMEM;
key_maps[s] = key_map;
key_map[0] = U(K_ALLOCATED);
for (j = 1; j < NR_KEYS; j++)
key_map[j] = U(K_HOLE);
keymap_count++;
}
ov = U(key_map[i]);
if (v == ov)
break; /* nothing to do */
/*
* Attention Key.
*/
if (((ov == K_SAK) || (v == K_SAK)) && !capable(CAP_SYS_ADMIN))
return -EPERM;
key_map[i] = U(v);
if (!s && (KTYP(ov) == KT_SHIFT || KTYP(v) == KT_SHIFT))
compute_shiftstate();
break;
}
return 0;
}
#undef i
#undef s
#undef v
static inline int
do_kbkeycode_ioctl(int cmd, struct kbkeycode __user *user_kbkc, int perm)
{
struct kbkeycode tmp;
int kc = 0;
if (copy_from_user(&tmp, user_kbkc, sizeof(struct kbkeycode)))
return -EFAULT;
switch (cmd) {
case KDGETKEYCODE:
kc = getkeycode(tmp.scancode);
if (kc >= 0)
kc = put_user(kc, &user_kbkc->keycode);
break;
case KDSETKEYCODE:
if (!perm)
return -EPERM;
kc = setkeycode(tmp.scancode, tmp.keycode);
break;
}
return kc;
}
static inline int
do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
{
struct kbsentry *kbs;
char *p;
u_char *q;
u_char __user *up;
int sz;
int delta;
char *first_free, *fj, *fnw;
int i, j, k;
int ret;
if (!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
kbs = kmalloc(sizeof(*kbs), GFP_KERNEL);
if (!kbs) {
ret = -ENOMEM;
goto reterr;
}
/* we mostly copy too much here (512bytes), but who cares ;) */
if (copy_from_user(kbs, user_kdgkb, sizeof(struct kbsentry))) {
ret = -EFAULT;
goto reterr;
}
kbs->kb_string[sizeof(kbs->kb_string)-1] = '\0';
i = kbs->kb_func;
switch (cmd) {
case KDGKBSENT:
sz = sizeof(kbs->kb_string) - 1; /* sz should have been
a struct member */
up = user_kdgkb->kb_string;
p = func_table[i];
if(p)
for ( ; *p && sz; p++, sz--)
if (put_user(*p, up++)) {
ret = -EFAULT;
goto reterr;
}
if (put_user('\0', up)) {
ret = -EFAULT;
goto reterr;
}
kfree(kbs);
return ((p && *p) ? -EOVERFLOW : 0);
case KDSKBSENT:
if (!perm) {
ret = -EPERM;
goto reterr;
}
q = func_table[i];
first_free = funcbufptr + (funcbufsize - funcbufleft);
for (j = i+1; j < MAX_NR_FUNC && !func_table[j]; j++)
;
if (j < MAX_NR_FUNC)
fj = func_table[j];
else
fj = first_free;
delta = (q ? -strlen(q) : 1) + strlen(kbs->kb_string);
if (delta <= funcbufleft) { /* it fits in current buf */
if (j < MAX_NR_FUNC) {
memmove(fj + delta, fj, first_free - fj);
for (k = j; k < MAX_NR_FUNC; k++)
if (func_table[k])
func_table[k] += delta;
}
if (!q)
func_table[i] = fj;
funcbufleft -= delta;
} else { /* allocate a larger buffer */
sz = 256;
while (sz < funcbufsize - funcbufleft + delta)
sz <<= 1;
fnw = kmalloc(sz, GFP_KERNEL);
if(!fnw) {
ret = -ENOMEM;
goto reterr;
}
if (!q)
func_table[i] = fj;
if (fj > funcbufptr)
memmove(fnw, funcbufptr, fj - funcbufptr);
for (k = 0; k < j; k++)
if (func_table[k])
func_table[k] = fnw + (func_table[k] - funcbufptr);
if (first_free > fj) {
memmove(fnw + (fj - funcbufptr) + delta, fj, first_free - fj);
for (k = j; k < MAX_NR_FUNC; k++)
if (func_table[k])
func_table[k] = fnw + (func_table[k] - funcbufptr) + delta;
}
if (funcbufptr != func_buf)
kfree(funcbufptr);
funcbufptr = fnw;
funcbufleft = funcbufleft - delta + sz - funcbufsize;
funcbufsize = sz;
}
strcpy(func_table[i], kbs->kb_string);
break;
}
ret = 0;
reterr:
kfree(kbs);
return ret;
}
static inline int
do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
{
struct consolefontdesc cfdarg;
int i;
if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
return -EFAULT;
switch (cmd) {
case PIO_FONTX:
if (!perm)
return -EPERM;
op->op = KD_FONT_OP_SET;
op->flags = KD_FONT_FLAG_OLD;
op->width = 8;
op->height = cfdarg.charheight;
op->charcount = cfdarg.charcount;
op->data = cfdarg.chardata;
return con_font_op(vc_cons[fg_console].d, op);
case GIO_FONTX: {
op->op = KD_FONT_OP_GET;
op->flags = KD_FONT_FLAG_OLD;
op->width = 8;
op->height = cfdarg.charheight;
op->charcount = cfdarg.charcount;
op->data = cfdarg.chardata;
i = con_font_op(vc_cons[fg_console].d, op);
if (i)
return i;
cfdarg.charheight = op->height;
cfdarg.charcount = op->charcount;
if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
return -EFAULT;
return 0;
}
}
return -EINVAL;
}
static inline int
do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
{
struct unimapdesc tmp;
if (copy_from_user(&tmp, user_ud, sizeof tmp))
return -EFAULT;
if (tmp.entries)
if (!access_ok(VERIFY_WRITE, tmp.entries,
tmp.entry_ct*sizeof(struct unipair)))
return -EFAULT;
switch (cmd) {
case PIO_UNIMAP:
if (!perm)
return -EPERM;
return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
case GIO_UNIMAP:
if (!perm && fg_console != vc->vc_num)
return -EPERM;
return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries);
}
return 0;
}
/*
* We handle the console-specific ioctl's here. We allow the
* capability to modify any console, not just the fg_console.
*/
int vt_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
struct kbd_struct * kbd;
unsigned int console;
unsigned char ucval;
void __user *up = (void __user *)arg;
int i, perm;
int ret = 0;
console = vc->vc_num;
lock_kernel();
if (!vc_cons_allocated(console)) { /* impossible? */
ret = -ENOIOCTLCMD;
goto out;
}
/*
* To have permissions to do most of the vt ioctls, we either have
* to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
*/
perm = 0;
if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
perm = 1;
kbd = kbd_table + console;
switch (cmd) {
case TIOCLINUX:
ret = tioclinux(tty, arg);
break;
case KIOCSOUND:
if (!perm)
goto eperm;
/* FIXME: This is an old broken API but we need to keep it
supported and somehow separate the historic advertised
tick rate from any real one */
if (arg)
arg = CLOCK_TICK_RATE / arg;
kd_mksound(arg, 0);
break;
case KDMKTONE:
if (!perm)
goto eperm;
{
unsigned int ticks, count;
/*
* Generate the tone for the appropriate number of ticks.
* If the time is zero, turn off sound ourselves.
*/
ticks = HZ * ((arg >> 16) & 0xffff) / 1000;
count = ticks ? (arg & 0xffff) : 0;
/* FIXME: This is an old broken API but we need to keep it
supported and somehow separate the historic advertised
tick rate from any real one */
if (count)
count = CLOCK_TICK_RATE / count;
kd_mksound(count, ticks);
break;
}
case KDGKBTYPE:
/*
* this is naive.
*/
ucval = KB_101;
goto setchar;
/*
* These cannot be implemented on any machine that implements
* ioperm() in user level (such as Alpha PCs) or not at all.
*
* XXX: you should never use these, just call ioperm directly..
*/
#ifdef CONFIG_X86
case KDADDIO:
case KDDELIO:
/*
* KDADDIO and KDDELIO may be able to add ports beyond what
* we reject here, but to be safe...
*/
if (arg < GPFIRST || arg > GPLAST) {
ret = -EINVAL;
break;
}
ret = sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
break;
case KDENABIO:
case KDDISABIO:
ret = sys_ioperm(GPFIRST, GPNUM,
(cmd == KDENABIO)) ? -ENXIO : 0;
break;
#endif
/* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
case KDKBDREP:
{
struct kbd_repeat kbrep;
if (!capable(CAP_SYS_TTY_CONFIG))
goto eperm;
if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
ret = -EFAULT;
break;
}
ret = kbd_rate(&kbrep);
if (ret)
break;
if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
ret = -EFAULT;
break;
}
case KDSETMODE:
/*
* currently, setting the mode from KD_TEXT to KD_GRAPHICS
* doesn't do a whole lot. i'm not sure if it should do any
* restoration of modes or what...
*
* XXX It should at least call into the driver, fbdev's definitely
* need to restore their engine state. --BenH
*/
if (!perm)
goto eperm;
switch (arg) {
case KD_GRAPHICS:
break;
case KD_TEXT0:
case KD_TEXT1:
arg = KD_TEXT;
case KD_TEXT:
break;
default:
ret = -EINVAL;
goto out;
}
if (vc->vc_mode == (unsigned char) arg)
break;
vc->vc_mode = (unsigned char) arg;
if (console != fg_console)
break;
/*
* explicitly blank/unblank the screen if switching modes
*/
acquire_console_sem();
if (arg == KD_TEXT)
do_unblank_screen(1);
else
do_blank_screen(1);
release_console_sem();
break;
case KDGETMODE:
ucval = vc->vc_mode;
goto setint;
case KDMAPDISP:
case KDUNMAPDISP:
/*
* these work like a combination of mmap and KDENABIO.
* this could be easily finished.
*/
ret = -EINVAL;
break;
case KDSKBMODE:
if (!perm)
goto eperm;
switch(arg) {
case K_RAW:
kbd->kbdmode = VC_RAW;
break;
case K_MEDIUMRAW:
kbd->kbdmode = VC_MEDIUMRAW;
break;
case K_XLATE:
kbd->kbdmode = VC_XLATE;
compute_shiftstate();
break;
case K_UNICODE:
kbd->kbdmode = VC_UNICODE;
compute_shiftstate();
break;
default:
ret = -EINVAL;
goto out;
}
tty_ldisc_flush(tty);
break;
case KDGKBMODE:
ucval = ((kbd->kbdmode == VC_RAW) ? K_RAW :
(kbd->kbdmode == VC_MEDIUMRAW) ? K_MEDIUMRAW :
(kbd->kbdmode == VC_UNICODE) ? K_UNICODE :
K_XLATE);
goto setint;
/* this could be folded into KDSKBMODE, but for compatibility
reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
case KDSKBMETA:
switch(arg) {
case K_METABIT:
clr_vc_kbd_mode(kbd, VC_META);
break;
case K_ESCPREFIX:
set_vc_kbd_mode(kbd, VC_META);
break;
default:
ret = -EINVAL;
}
break;
case KDGKBMETA:
ucval = (vc_kbd_mode(kbd, VC_META) ? K_ESCPREFIX : K_METABIT);
setint:
ret = put_user(ucval, (int __user *)arg);
break;
case KDGETKEYCODE:
case KDSETKEYCODE:
if(!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
ret = do_kbkeycode_ioctl(cmd, up, perm);
break;
case KDGKBENT:
case KDSKBENT:
ret = do_kdsk_ioctl(cmd, up, perm, kbd);
break;
case KDGKBSENT:
case KDSKBSENT:
ret = do_kdgkb_ioctl(cmd, up, perm);
break;
case KDGKBDIACR:
{
struct kbdiacrs __user *a = up;
struct kbdiacr diacr;
int i;
if (put_user(accent_table_size, &a->kb_cnt)) {
ret = -EFAULT;
break;
}
for (i = 0; i < accent_table_size; i++) {
diacr.diacr = conv_uni_to_8bit(accent_table[i].diacr);
diacr.base = conv_uni_to_8bit(accent_table[i].base);
diacr.result = conv_uni_to_8bit(accent_table[i].result);
if (copy_to_user(a->kbdiacr + i, &diacr, sizeof(struct kbdiacr))) {
ret = -EFAULT;
break;
}
}
break;
}
case KDGKBDIACRUC:
{
struct kbdiacrsuc __user *a = up;
if (put_user(accent_table_size, &a->kb_cnt))
ret = -EFAULT;
else if (copy_to_user(a->kbdiacruc, accent_table,
accent_table_size*sizeof(struct kbdiacruc)))
ret = -EFAULT;
break;
}
case KDSKBDIACR:
{
struct kbdiacrs __user *a = up;
struct kbdiacr diacr;
unsigned int ct;
int i;
if (!perm)
goto eperm;
if (get_user(ct,&a->kb_cnt)) {
ret = -EFAULT;
break;
}
if (ct >= MAX_DIACR) {
ret = -EINVAL;
break;
}
accent_table_size = ct;
for (i = 0; i < ct; i++) {
if (copy_from_user(&diacr, a->kbdiacr + i, sizeof(struct kbdiacr))) {
ret = -EFAULT;
break;
}
accent_table[i].diacr = conv_8bit_to_uni(diacr.diacr);
accent_table[i].base = conv_8bit_to_uni(diacr.base);
accent_table[i].result = conv_8bit_to_uni(diacr.result);
}
break;
}
case KDSKBDIACRUC:
{
struct kbdiacrsuc __user *a = up;
unsigned int ct;
if (!perm)
goto eperm;
if (get_user(ct,&a->kb_cnt)) {
ret = -EFAULT;
break;
}
if (ct >= MAX_DIACR) {
ret = -EINVAL;
break;
}
accent_table_size = ct;
if (copy_from_user(accent_table, a->kbdiacruc, ct*sizeof(struct kbdiacruc)))
ret = -EFAULT;
break;
}
/* the ioctls below read/set the flags usually shown in the leds */
/* don't use them - they will go away without warning */
case KDGKBLED:
ucval = kbd->ledflagstate | (kbd->default_ledflagstate << 4);
goto setchar;
case KDSKBLED:
if (!perm)
goto eperm;
if (arg & ~0x77) {
ret = -EINVAL;
break;
}
kbd->ledflagstate = (arg & 7);
kbd->default_ledflagstate = ((arg >> 4) & 7);
set_leds();
break;
/* the ioctls below only set the lights, not the functions */
/* for those, see KDGKBLED and KDSKBLED above */
case KDGETLED:
ucval = getledstate();
setchar:
ret = put_user(ucval, (char __user *)arg);
break;
case KDSETLED:
if (!perm)
goto eperm;
setledstate(kbd, arg);
break;
/*
* A process can indicate its willingness to accept signals
* generated by pressing an appropriate key combination.
* Thus, one can have a daemon that e.g. spawns a new console
* upon a keypress and then changes to it.
* See also the kbrequest field of inittab(5).
*/
case KDSIGACCEPT:
{
if (!perm || !capable(CAP_KILL))
goto eperm;
if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
ret = -EINVAL;
else {
spin_lock_irq(&vt_spawn_con.lock);
put_pid(vt_spawn_con.pid);
vt_spawn_con.pid = get_pid(task_pid(current));
vt_spawn_con.sig = arg;
spin_unlock_irq(&vt_spawn_con.lock);
}
break;
}
case VT_SETMODE:
{
struct vt_mode tmp;
if (!perm)
goto eperm;
if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
ret = -EFAULT;
goto out;
}
if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
ret = -EINVAL;
goto out;
}
acquire_console_sem();
vc->vt_mode = tmp;
/* the frsig is ignored, so we set it to 0 */
vc->vt_mode.frsig = 0;
put_pid(vc->vt_pid);
vc->vt_pid = get_pid(task_pid(current));
/* no switch is required -- saw@shade.msu.ru */
vc->vt_newvt = -1;
release_console_sem();
break;
}
case VT_GETMODE:
{
struct vt_mode tmp;
int rc;
acquire_console_sem();
memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
release_console_sem();
rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
if (rc)
ret = -EFAULT;
break;
}
/*
* Returns global vt state. Note that VT 0 is always open, since
* it's an alias for the current VT, and people can't use it here.
* We cannot return state for more than 16 VTs, since v_state is short.
*/
case VT_GETSTATE:
{
struct vt_stat __user *vtstat = up;
unsigned short state, mask;
if (put_user(fg_console + 1, &vtstat->v_active))
ret = -EFAULT;
else {
state = 1; /* /dev/tty0 is always open */
for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
++i, mask <<= 1)
if (VT_IS_IN_USE(i))
state |= mask;
ret = put_user(state, &vtstat->v_state);
}
break;
}
/*
* Returns the first available (non-opened) console.
*/
case VT_OPENQRY:
for (i = 0; i < MAX_NR_CONSOLES; ++i)
if (! VT_IS_IN_USE(i))
break;
ucval = i < MAX_NR_CONSOLES ? (i+1) : -1;
goto setint;
/*
* ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
* with num >= 1 (switches to vt 0, our console, are not allowed, just
* to preserve sanity).
*/
case VT_ACTIVATE:
if (!perm)
goto eperm;
if (arg == 0 || arg > MAX_NR_CONSOLES)
ret = -ENXIO;
else {
arg--;
acquire_console_sem();
ret = vc_allocate(arg);
release_console_sem();
if (ret)
break;
set_console(arg);
}
break;
case VT_SETACTIVATE:
{
struct vt_setactivate vsa;
if (!perm)
goto eperm;
if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
sizeof(struct vt_setactivate))) {
ret = -EFAULT;
goto out;
}
if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
ret = -ENXIO;
else {
vsa.console--;
acquire_console_sem();
ret = vc_allocate(vsa.console);
if (ret == 0) {
struct vc_data *nvc;
/* This is safe providing we don't drop the
console sem between vc_allocate and
finishing referencing nvc */
nvc = vc_cons[vsa.console].d;
nvc->vt_mode = vsa.mode;
nvc->vt_mode.frsig = 0;
put_pid(nvc->vt_pid);
nvc->vt_pid = get_pid(task_pid(current));
}
release_console_sem();
if (ret)
break;
/* Commence switch and lock */
set_console(arg);
}
}
/*
* wait until the specified VT has been activated
*/
case VT_WAITACTIVE:
if (!perm)
goto eperm;
if (arg == 0 || arg > MAX_NR_CONSOLES)
ret = -ENXIO;
else
ret = vt_waitactive(arg);
break;
/*
* If a vt is under process control, the kernel will not switch to it
* immediately, but postpone the operation until the process calls this
* ioctl, allowing the switch to complete.
*
* According to the X sources this is the behavior:
* 0: pending switch-from not OK
* 1: pending switch-from OK
* 2: completed switch-to OK
*/
case VT_RELDISP:
if (!perm)
goto eperm;
if (vc->vt_mode.mode != VT_PROCESS) {
ret = -EINVAL;
break;
}
/*
* Switching-from response
*/
acquire_console_sem();
if (vc->vt_newvt >= 0) {
if (arg == 0)
/*
* Switch disallowed, so forget we were trying
* to do it.
*/
vc->vt_newvt = -1;
else {
/*
* The current vt has been released, so
* complete the switch.
*/
int newvt;
newvt = vc->vt_newvt;
vc->vt_newvt = -1;
ret = vc_allocate(newvt);
if (ret) {
release_console_sem();
break;
}
/*
* When we actually do the console switch,
* make sure we are atomic with respect to
* other console switches..
*/
complete_change_console(vc_cons[newvt].d);
}
} else {
/*
* Switched-to response
*/
/*
* If it's just an ACK, ignore it
*/
if (arg != VT_ACKACQ)
ret = -EINVAL;
}
release_console_sem();
break;
/*
* Disallocate memory associated to VT (but leave VT1)
*/
case VT_DISALLOCATE:
if (arg > MAX_NR_CONSOLES) {
ret = -ENXIO;
break;
}
if (arg == 0) {
/* deallocate all unused consoles, but leave 0 */
acquire_console_sem();
for (i=1; i<MAX_NR_CONSOLES; i++)
if (! VT_BUSY(i))
vc_deallocate(i);
release_console_sem();
} else {
/* deallocate a single console, if possible */
arg--;
if (VT_BUSY(arg))
ret = -EBUSY;
else if (arg) { /* leave 0 */
acquire_console_sem();
vc_deallocate(arg);
release_console_sem();
}
}
break;
case VT_RESIZE:
{
struct vt_sizes __user *vtsizes = up;
struct vc_data *vc;
ushort ll,cc;
if (!perm)
goto eperm;
if (get_user(ll, &vtsizes->v_rows) ||
get_user(cc, &vtsizes->v_cols))
ret = -EFAULT;
else {
acquire_console_sem();
for (i = 0; i < MAX_NR_CONSOLES; i++) {
vc = vc_cons[i].d;
if (vc) {
vc->vc_resize_user = 1;
vc_resize(vc_cons[i].d, cc, ll);
}
}
release_console_sem();
}
break;
}
case VT_RESIZEX:
{
struct vt_consize __user *vtconsize = up;
ushort ll,cc,vlin,clin,vcol,ccol;
if (!perm)
goto eperm;
if (!access_ok(VERIFY_READ, vtconsize,
sizeof(struct vt_consize))) {
ret = -EFAULT;
break;
}
/* FIXME: Should check the copies properly */
__get_user(ll, &vtconsize->v_rows);
__get_user(cc, &vtconsize->v_cols);
__get_user(vlin, &vtconsize->v_vlin);
__get_user(clin, &vtconsize->v_clin);
__get_user(vcol, &vtconsize->v_vcol);
__get_user(ccol, &vtconsize->v_ccol);
vlin = vlin ? vlin : vc->vc_scan_lines;
if (clin) {
if (ll) {
if (ll != vlin/clin) {
/* Parameters don't add up */
ret = -EINVAL;
break;
}
} else
ll = vlin/clin;
}
if (vcol && ccol) {
if (cc) {
if (cc != vcol/ccol) {
ret = -EINVAL;
break;
}
} else
cc = vcol/ccol;
}
if (clin > 32) {
ret = -EINVAL;
break;
}
for (i = 0; i < MAX_NR_CONSOLES; i++) {
if (!vc_cons[i].d)
continue;
acquire_console_sem();
if (vlin)
vc_cons[i].d->vc_scan_lines = vlin;
if (clin)
vc_cons[i].d->vc_font.height = clin;
vc_cons[i].d->vc_resize_user = 1;
vc_resize(vc_cons[i].d, cc, ll);
release_console_sem();
}
break;
}
case PIO_FONT: {
if (!perm)
goto eperm;
op.op = KD_FONT_OP_SET;
op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
op.width = 8;
op.height = 0;
op.charcount = 256;
op.data = up;
ret = con_font_op(vc_cons[fg_console].d, &op);
break;
}
case GIO_FONT: {
op.op = KD_FONT_OP_GET;
op.flags = KD_FONT_FLAG_OLD;
op.width = 8;
op.height = 32;
op.charcount = 256;
op.data = up;
ret = con_font_op(vc_cons[fg_console].d, &op);
break;
}
case PIO_CMAP:
if (!perm)
ret = -EPERM;
else
ret = con_set_cmap(up);
break;
case GIO_CMAP:
ret = con_get_cmap(up);
break;
case PIO_FONTX:
case GIO_FONTX:
ret = do_fontx_ioctl(cmd, up, perm, &op);
break;
case PIO_FONTRESET:
{
if (!perm)
goto eperm;
#ifdef BROKEN_GRAPHICS_PROGRAMS
/* With BROKEN_GRAPHICS_PROGRAMS defined, the default
font is not saved. */
ret = -ENOSYS;
break;
#else
{
op.op = KD_FONT_OP_SET_DEFAULT;
op.data = NULL;
ret = con_font_op(vc_cons[fg_console].d, &op);
if (ret)
break;
con_set_default_unimap(vc_cons[fg_console].d);
break;
}
#endif
}
case KDFONTOP: {
if (copy_from_user(&op, up, sizeof(op))) {
ret = -EFAULT;
break;
}
if (!perm && op.op != KD_FONT_OP_GET)
goto eperm;
ret = con_font_op(vc, &op);
if (ret)
break;
if (copy_to_user(up, &op, sizeof(op)))
ret = -EFAULT;
break;
}
case PIO_SCRNMAP:
if (!perm)
ret = -EPERM;
else
ret = con_set_trans_old(up);
break;
case GIO_SCRNMAP:
ret = con_get_trans_old(up);
break;
case PIO_UNISCRNMAP:
if (!perm)
ret = -EPERM;
else
ret = con_set_trans_new(up);
break;
case GIO_UNISCRNMAP:
ret = con_get_trans_new(up);
break;
case PIO_UNIMAPCLR:
{ struct unimapinit ui;
if (!perm)
goto eperm;
ret = copy_from_user(&ui, up, sizeof(struct unimapinit));
if (!ret)
con_clear_unimap(vc, &ui);
break;
}
case PIO_UNIMAP:
case GIO_UNIMAP:
ret = do_unimap_ioctl(cmd, up, perm, vc);
break;
case VT_LOCKSWITCH:
if (!capable(CAP_SYS_TTY_CONFIG))
goto eperm;
vt_dont_switch = 1;
break;
case VT_UNLOCKSWITCH:
if (!capable(CAP_SYS_TTY_CONFIG))
goto eperm;
vt_dont_switch = 0;
break;
case VT_GETHIFONTMASK:
ret = put_user(vc->vc_hi_font_mask,
(unsigned short __user *)arg);
break;
case VT_WAITEVENT:
ret = vt_event_wait_ioctl((struct vt_event __user *)arg);
break;
default:
ret = -ENOIOCTLCMD;
}
out:
unlock_kernel();
return ret;
eperm:
ret = -EPERM;
goto out;
}
void reset_vc(struct vc_data *vc)
{
vc->vc_mode = KD_TEXT;
kbd_table[vc->vc_num].kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE;
vc->vt_mode.mode = VT_AUTO;
vc->vt_mode.waitv = 0;
vc->vt_mode.relsig = 0;
vc->vt_mode.acqsig = 0;
vc->vt_mode.frsig = 0;
put_pid(vc->vt_pid);
vc->vt_pid = NULL;
vc->vt_newvt = -1;
if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
reset_palette(vc);
}
void vc_SAK(struct work_struct *work)
{
struct vc *vc_con =
container_of(work, struct vc, SAK_work);
struct vc_data *vc;
struct tty_struct *tty;
acquire_console_sem();
vc = vc_con->d;
if (vc) {
tty = vc->vc_tty;
/*
* SAK should also work in all raw modes and reset
* them properly.
*/
if (tty)
__do_SAK(tty);
reset_vc(vc);
}
release_console_sem();
}
#ifdef CONFIG_COMPAT
struct compat_consolefontdesc {
unsigned short charcount; /* characters in font (256 or 512) */
unsigned short charheight; /* scan lines per character (1-32) */
compat_caddr_t chardata; /* font data in expanded form */
};
static inline int
compat_fontx_ioctl(int cmd, struct compat_consolefontdesc __user *user_cfd,
int perm, struct console_font_op *op)
{
struct compat_consolefontdesc cfdarg;
int i;
if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc)))
return -EFAULT;
switch (cmd) {
case PIO_FONTX:
if (!perm)
return -EPERM;
op->op = KD_FONT_OP_SET;
op->flags = KD_FONT_FLAG_OLD;
op->width = 8;
op->height = cfdarg.charheight;
op->charcount = cfdarg.charcount;
op->data = compat_ptr(cfdarg.chardata);
return con_font_op(vc_cons[fg_console].d, op);
case GIO_FONTX:
op->op = KD_FONT_OP_GET;
op->flags = KD_FONT_FLAG_OLD;
op->width = 8;
op->height = cfdarg.charheight;
op->charcount = cfdarg.charcount;
op->data = compat_ptr(cfdarg.chardata);
i = con_font_op(vc_cons[fg_console].d, op);
if (i)
return i;
cfdarg.charheight = op->height;
cfdarg.charcount = op->charcount;
if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc)))
return -EFAULT;
return 0;
}
return -EINVAL;
}
struct compat_console_font_op {
compat_uint_t op; /* operation code KD_FONT_OP_* */
compat_uint_t flags; /* KD_FONT_FLAG_* */
compat_uint_t width, height; /* font size */
compat_uint_t charcount;
compat_caddr_t data; /* font data with height fixed to 32 */
};
static inline int
compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
int perm, struct console_font_op *op, struct vc_data *vc)
{
int i;
if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op)))
return -EFAULT;
if (!perm && op->op != KD_FONT_OP_GET)
return -EPERM;
op->data = compat_ptr(((struct compat_console_font_op *)op)->data);
op->flags |= KD_FONT_FLAG_OLD;
i = con_font_op(vc, op);
if (i)
return i;
((struct compat_console_font_op *)op)->data = (unsigned long)op->data;
if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op)))
return -EFAULT;
return 0;
}
struct compat_unimapdesc {
unsigned short entry_ct;
compat_caddr_t entries;
};
static inline int
compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
int perm, struct vc_data *vc)
{
struct compat_unimapdesc tmp;
struct unipair __user *tmp_entries;
if (copy_from_user(&tmp, user_ud, sizeof tmp))
return -EFAULT;
tmp_entries = compat_ptr(tmp.entries);
if (tmp_entries)
if (!access_ok(VERIFY_WRITE, tmp_entries,
tmp.entry_ct*sizeof(struct unipair)))
return -EFAULT;
switch (cmd) {
case PIO_UNIMAP:
if (!perm)
return -EPERM;
return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
case GIO_UNIMAP:
if (!perm && fg_console != vc->vc_num)
return -EPERM;
return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
}
return 0;
}
long vt_compat_ioctl(struct tty_struct *tty, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
struct kbd_struct *kbd;
unsigned int console;
void __user *up = (void __user *)arg;
int perm;
int ret = 0;
console = vc->vc_num;
lock_kernel();
if (!vc_cons_allocated(console)) { /* impossible? */
ret = -ENOIOCTLCMD;
goto out;
}
/*
* To have permissions to do most of the vt ioctls, we either have
* to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
*/
perm = 0;
if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
perm = 1;
kbd = kbd_table + console;
switch (cmd) {
/*
* these need special handlers for incompatible data structures
*/
case PIO_FONTX:
case GIO_FONTX:
ret = compat_fontx_ioctl(cmd, up, perm, &op);
break;
case KDFONTOP:
ret = compat_kdfontop_ioctl(up, perm, &op, vc);
break;
case PIO_UNIMAP:
case GIO_UNIMAP:
ret = do_unimap_ioctl(cmd, up, perm, vc);
break;
/*
* all these treat 'arg' as an integer
*/
case KIOCSOUND:
case KDMKTONE:
#ifdef CONFIG_X86
case KDADDIO:
case KDDELIO:
#endif
case KDSETMODE:
case KDMAPDISP:
case KDUNMAPDISP:
case KDSKBMODE:
case KDSKBMETA:
case KDSKBLED:
case KDSETLED:
case KDSIGACCEPT:
case VT_ACTIVATE:
case VT_WAITACTIVE:
case VT_RELDISP:
case VT_DISALLOCATE:
case VT_RESIZE:
case VT_RESIZEX:
goto fallback;
/*
* the rest has a compatible data structure behind arg,
* but we have to convert it to a proper 64 bit pointer.
*/
default:
arg = (unsigned long)compat_ptr(arg);
goto fallback;
}
out:
unlock_kernel();
return ret;
fallback:
unlock_kernel();
return vt_ioctl(tty, file, cmd, arg);
}
#endif /* CONFIG_COMPAT */
/*
* Performs the back end of a vt switch. Called under the console
* semaphore.
*/
static void complete_change_console(struct vc_data *vc)
{
unsigned char old_vc_mode;
int old = fg_console;
last_console = fg_console;
/*
* If we're switching, we could be going from KD_GRAPHICS to
* KD_TEXT mode or vice versa, which means we need to blank or
* unblank the screen later.
*/
old_vc_mode = vc_cons[fg_console].d->vc_mode;
switch_screen(vc);
/*
* This can't appear below a successful kill_pid(). If it did,
* then the *blank_screen operation could occur while X, having
* received acqsig, is waking up on another processor. This
* condition can lead to overlapping accesses to the VGA range
* and the framebuffer (causing system lockups).
*
* To account for this we duplicate this code below only if the
* controlling process is gone and we've called reset_vc.
*/
if (old_vc_mode != vc->vc_mode) {
if (vc->vc_mode == KD_TEXT)
do_unblank_screen(1);
else
do_blank_screen(1);
}
/*
* If this new console is under process control, send it a signal
* telling it that it has acquired. Also check if it has died and
* clean up (similar to logic employed in change_console())
*/
if (vc->vt_mode.mode == VT_PROCESS) {
/*
* Send the signal as privileged - kill_pid() will
* tell us if the process has gone or something else
* is awry
*/
if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
/*
* The controlling process has died, so we revert back to
* normal operation. In this case, we'll also change back
* to KD_TEXT mode. I'm not sure if this is strictly correct
* but it saves the agony when the X server dies and the screen
* remains blanked due to KD_GRAPHICS! It would be nice to do
* this outside of VT_PROCESS but there is no single process
* to account for and tracking tty count may be undesirable.
*/
reset_vc(vc);
if (old_vc_mode != vc->vc_mode) {
if (vc->vc_mode == KD_TEXT)
do_unblank_screen(1);
else
do_blank_screen(1);
}
}
}
/*
* Wake anyone waiting for their VT to activate
*/
vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num);
return;
}
/*
* Performs the front-end of a vt switch
*/
void change_console(struct vc_data *new_vc)
{
struct vc_data *vc;
if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
return;
/*
* If this vt is in process mode, then we need to handshake with
* that process before switching. Essentially, we store where that
* vt wants to switch to and wait for it to tell us when it's done
* (via VT_RELDISP ioctl).
*
* We also check to see if the controlling process still exists.
* If it doesn't, we reset this vt to auto mode and continue.
* This is a cheap way to track process control. The worst thing
* that can happen is: we send a signal to a process, it dies, and
* the switch gets "lost" waiting for a response; hopefully, the
* user will try again, we'll detect the process is gone (unless
* the user waits just the right amount of time :-) and revert the
* vt to auto control.
*/
vc = vc_cons[fg_console].d;
if (vc->vt_mode.mode == VT_PROCESS) {
/*
* Send the signal as privileged - kill_pid() will
* tell us if the process has gone or something else
* is awry.
*
* We need to set vt_newvt *before* sending the signal or we
* have a race.
*/
vc->vt_newvt = new_vc->vc_num;
if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
/*
* It worked. Mark the vt to switch to and
* return. The process needs to send us a
* VT_RELDISP ioctl to complete the switch.
*/
return;
}
/*
* The controlling process has died, so we revert back to
* normal operation. In this case, we'll also change back
* to KD_TEXT mode. I'm not sure if this is strictly correct
* but it saves the agony when the X server dies and the screen
* remains blanked due to KD_GRAPHICS! It would be nice to do
* this outside of VT_PROCESS but there is no single process
* to account for and tracking tty count may be undesirable.
*/
reset_vc(vc);
/*
* Fall through to normal (VT_AUTO) handling of the switch...
*/
}
/*
* Ignore all switches in KD_GRAPHICS+VT_AUTO mode
*/
if (vc->vc_mode == KD_GRAPHICS)
return;
complete_change_console(new_vc);
}
/* Perform a kernel triggered VT switch for suspend/resume */
static int disable_vt_switch;
int vt_move_to_console(unsigned int vt, int alloc)
{
int prev;
acquire_console_sem();
/* Graphics mode - up to X */
if (disable_vt_switch) {
release_console_sem();
return 0;
}
prev = fg_console;
if (alloc && vc_allocate(vt)) {
/* we can't have a free VC for now. Too bad,
* we don't want to mess the screen for now. */
release_console_sem();
return -ENOSPC;
}
if (set_console(vt)) {
/*
* We're unable to switch to the SUSPEND_CONSOLE.
* Let the calling function know so it can decide
* what to do.
*/
release_console_sem();
return -EIO;
}
release_console_sem();
if (vt_waitactive(vt + 1)) {
pr_debug("Suspend: Can't switch VCs.");
return -EINTR;
}
return prev;
}
/*
* Normally during a suspend, we allocate a new console and switch to it.
* When we resume, we switch back to the original console. This switch
* can be slow, so on systems where the framebuffer can handle restoration
* of video registers anyways, there's little point in doing the console
* switch. This function allows you to disable it by passing it '0'.
*/
void pm_set_vt_switch(int do_switch)
{
acquire_console_sem();
disable_vt_switch = !do_switch;
release_console_sem();
}
EXPORT_SYMBOL(pm_set_vt_switch);
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