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kernel_samsung_a34x-permissive/drivers/tty/vt/vt_ioctl.c

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Import A346BXXU1AWB9 kernel source Android 13
2024-04-28 06:49:01 -07:00
// SPDX-License-Identifier: GPL-2.0
/*
* 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/signal.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/suspend.h>
#include <linux/timex.h>
#include <asm/io.h>
#include <linux/uaccess.h>
#include <linux/nospec.h>
#include <linux/kbd_kern.h>
#include <linux/vt_kern.h>
#include <linux/kbd_diacr.h>
#include <linux/selection.h>
bool vt_dont_switch;
static inline bool vt_in_use(unsigned int i)
{
const struct vc_data *vc = vc_cons[i].d;
/*
* console_lock must be held to prevent the vc from being deallocated
* while we're checking whether it's in-use.
*/
WARN_CONSOLE_UNLOCKED();
return vc && kref_read(&vc->port.kref) > 1;
}
static inline bool vt_busy(int i)
{
if (vt_in_use(i))
return true;
if (i == fg_console)
return true;
if (vc_is_sel(vc_cons[i].d))
return true;
return false;
}
/*
* 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 <asm/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.oldev = old + 1;
ve->event.newev = new + 1;
wake = 1;
ve->done = 1;
}
spin_unlock_irqrestore(&vt_event_lock, flags);
if (wake)
wake_up_interruptible(&vt_event_waitqueue);
}
static void __vt_event_queue(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);
}
static void __vt_event_wait(struct vt_event_wait *vw)
{
/* Wait for it to pass */
wait_event_interruptible(vt_event_waitqueue, vw->done);
}
static void __vt_event_dequeue(struct vt_event_wait *vw)
{
unsigned long flags;
/* Dequeue it */
spin_lock_irqsave(&vt_event_lock, flags);
list_del(&vw->list);
spin_unlock_irqrestore(&vt_event_lock, flags);
}
/**
* 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)
{
__vt_event_queue(vw);
__vt_event_wait(vw);
__vt_event_dequeue(vw);
}
/**
* 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 {
vw.event.event = VT_EVENT_SWITCH;
__vt_event_queue(&vw);
if (n == fg_console + 1) {
__vt_event_dequeue(&vw);
break;
}
__vt_event_wait(&vw);
__vt_event_dequeue(&vw);
if (vw.done == 0)
return -EINTR;
} while (vw.event.newev != 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)
static inline int
do_fontx_ioctl(struct vc_data *vc, 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, 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, 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;
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;
}
/* deallocate a single console, if possible (leave 0) */
static int vt_disallocate(unsigned int vc_num)
{
struct vc_data *vc = NULL;
int ret = 0;
console_lock();
if (vt_busy(vc_num))
ret = -EBUSY;
else if (vc_num)
vc = vc_deallocate(vc_num);
console_unlock();
if (vc && vc_num >= MIN_NR_CONSOLES)
tty_port_put(&vc->port);
return ret;
}
/* deallocate all unused consoles, but leave 0 */
static void vt_disallocate_all(void)
{
struct vc_data *vc[MAX_NR_CONSOLES];
int i;
console_lock();
for (i = 1; i < MAX_NR_CONSOLES; i++)
if (!vt_busy(i))
vc[i] = vc_deallocate(i);
else
vc[i] = NULL;
console_unlock();
for (i = 1; i < MAX_NR_CONSOLES; i++) {
if (vc[i] && i >= MIN_NR_CONSOLES)
tty_port_put(&vc[i]->port);
}
}
/*
* 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,
unsigned int cmd, unsigned long arg)
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
unsigned int console = vc->vc_num;
unsigned char ucval;
unsigned int uival;
void __user *up = (void __user *)arg;
int i, perm;
int ret = 0;
/*
* 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;
switch (cmd) {
case TIOCLINUX:
ret = tioclinux(tty, arg);
break;
case KIOCSOUND:
if (!perm)
return -EPERM;
/*
* The use of PIT_TICK_RATE is historic, it used to be
* the platform-dependent CLOCK_TICK_RATE between 2.6.12
* and 2.6.36, which was a minor but unfortunate ABI
* change. kd_mksound is locked by the input layer.
*/
if (arg)
arg = PIT_TICK_RATE / arg;
kd_mksound(arg, 0);
break;
case KDMKTONE:
if (!perm)
return -EPERM;
{
unsigned int ticks, count;
/*
* Generate the tone for the appropriate number of ticks.
* If the time is zero, turn off sound ourselves.
*/
ticks = msecs_to_jiffies((arg >> 16) & 0xffff);
count = ticks ? (arg & 0xffff) : 0;
if (count)
count = PIT_TICK_RATE / count;
kd_mksound(count, ticks);
break;
}
case KDGKBTYPE:
/*
* this is naïve.
*/
ucval = KB_101;
ret = put_user(ucval, (char __user *)arg);
break;
/*
* 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...
*
* These are locked internally via sys_ioperm
*/
if (arg < GPFIRST || arg > GPLAST) {
ret = -EINVAL;
break;
}
ret = ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
break;
case KDENABIO:
case KDDISABIO:
ret = ksys_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))
return -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)
return -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;
}
/* FIXME: this needs the console lock extending */
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
*/
console_lock();
if (arg == KD_TEXT)
do_unblank_screen(1);
else
do_blank_screen(1);
console_unlock();
break;
case KDGETMODE:
uival = 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)
return -EPERM;
ret = vt_do_kdskbmode(console, arg);
if (ret == 0)
tty_ldisc_flush(tty);
break;
case KDGKBMODE:
uival = vt_do_kdgkbmode(console);
ret = put_user(uival, (int __user *)arg);
break;
/* this could be folded into KDSKBMODE, but for compatibility
reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
case KDSKBMETA:
ret = vt_do_kdskbmeta(console, arg);
break;
case KDGKBMETA:
/* FIXME: should review whether this is worth locking */
uival = vt_do_kdgkbmeta(console);
setint:
ret = put_user(uival, (int __user *)arg);
break;
case KDGETKEYCODE:
case KDSETKEYCODE:
if(!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
ret = vt_do_kbkeycode_ioctl(cmd, up, perm);
break;
case KDGKBENT:
case KDSKBENT:
ret = vt_do_kdsk_ioctl(cmd, up, perm, console);
break;
case KDGKBSENT:
case KDSKBSENT:
ret = vt_do_kdgkb_ioctl(cmd, up, perm);
break;
/* Diacritical processing. Handled in keyboard.c as it has
to operate on the keyboard locks and structures */
case KDGKBDIACR:
case KDGKBDIACRUC:
case KDSKBDIACR:
case KDSKBDIACRUC:
ret = vt_do_diacrit(cmd, up, perm);
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:
case KDSKBLED:
case KDGETLED:
case KDSETLED:
ret = vt_do_kdskled(console, cmd, arg, perm);
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))
return -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)
return -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;
}
console_lock();
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;
console_unlock();
break;
}
case VT_GETMODE:
{
struct vt_mode tmp;
int rc;
console_lock();
memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
console_unlock();
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 */
console_lock(); /* required by vt_in_use() */
for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
++i, mask <<= 1)
if (vt_in_use(i))
state |= mask;
console_unlock();
ret = put_user(state, &vtstat->v_state);
}
break;
}
/*
* Returns the first available (non-opened) console.
*/
case VT_OPENQRY:
console_lock(); /* required by vt_in_use() */
for (i = 0; i < MAX_NR_CONSOLES; ++i)
if (!vt_in_use(i))
break;
console_unlock();
uival = 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)
return -EPERM;
if (arg == 0 || arg > MAX_NR_CONSOLES)
ret = -ENXIO;
else {
arg--;
console_lock();
ret = vc_allocate(arg);
console_unlock();
if (ret)
break;
set_console(arg);
}
break;
case VT_SETACTIVATE:
{
struct vt_setactivate vsa;
if (!perm)
return -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 = array_index_nospec(vsa.console,
MAX_NR_CONSOLES + 1);
vsa.console--;
console_lock();
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));
}
console_unlock();
if (ret)
break;
/* Commence switch and lock */
/* Review set_console locks */
set_console(vsa.console);
}
break;
}
/*
* wait until the specified VT has been activated
*/
case VT_WAITACTIVE:
if (!perm)
return -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)
return -EPERM;
console_lock();
if (vc->vt_mode.mode != VT_PROCESS) {
console_unlock();
ret = -EINVAL;
break;
}
/*
* Switching-from response
*/
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) {
console_unlock();
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;
}
console_unlock();
break;
/*
* Disallocate memory associated to VT (but leave VT1)
*/
case VT_DISALLOCATE:
if (arg > MAX_NR_CONSOLES) {
ret = -ENXIO;
break;
}
if (arg == 0)
vt_disallocate_all();
else
ret = vt_disallocate(--arg);
break;
case VT_RESIZE:
{
struct vt_sizes __user *vtsizes = up;
struct vc_data *vc;
ushort ll,cc;
if (!perm)
return -EPERM;
if (get_user(ll, &vtsizes->v_rows) ||
get_user(cc, &vtsizes->v_cols))
ret = -EFAULT;
else {
console_lock();
for (i = 0; i < MAX_NR_CONSOLES; i++) {
vc = vc_cons[i].d;
if (vc) {
vc->vc_resize_user = 1;
/* FIXME: review v tty lock */
vc_resize(vc_cons[i].d, cc, ll);
}
}
console_unlock();
}
break;
}
case VT_RESIZEX:
{
struct vt_consize v;
if (!perm)
return -EPERM;
if (copy_from_user(&v, up, sizeof(struct vt_consize)))
return -EFAULT;
/* FIXME: Should check the copies properly */
if (!v.v_vlin)
v.v_vlin = vc->vc_scan_lines;
if (v.v_clin) {
int rows = v.v_vlin/v.v_clin;
if (v.v_rows != rows) {
if (v.v_rows) /* Parameters don't add up */
return -EINVAL;
v.v_rows = rows;
}
}
if (v.v_vcol && v.v_ccol) {
int cols = v.v_vcol/v.v_ccol;
if (v.v_cols != cols) {
if (v.v_cols)
return -EINVAL;
v.v_cols = cols;
}
}
if (v.v_clin > 32)
return -EINVAL;
for (i = 0; i < MAX_NR_CONSOLES; i++) {
struct vc_data *vcp;
if (!vc_cons[i].d)
continue;
console_lock();
vcp = vc_cons[i].d;
if (vcp) {
int ret;
int save_scan_lines = vcp->vc_scan_lines;
int save_font_height = vcp->vc_font.height;
if (v.v_vlin)
vcp->vc_scan_lines = v.v_vlin;
if (v.v_clin)
vcp->vc_font.height = v.v_clin;
vcp->vc_resize_user = 1;
ret = vc_resize(vcp, v.v_cols, v.v_rows);
if (ret) {
vcp->vc_scan_lines = save_scan_lines;
vcp->vc_font.height = save_font_height;
console_unlock();
return ret;
}
}
console_unlock();
}
break;
}
case PIO_FONT: {
if (!perm)
return -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, &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, &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(vc, cmd, up, perm, &op);
break;
case PIO_FONTRESET:
{
if (!perm)
return -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, &op);
if (ret)
break;
console_lock();
con_set_default_unimap(vc);
console_unlock();
break;
}
#endif
}
case KDFONTOP: {
if (copy_from_user(&op, up, sizeof(op))) {
ret = -EFAULT;
break;
}
if (!perm && op.op != KD_FONT_OP_GET)
return -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:
if (!perm)
return -EPERM;
con_clear_unimap(vc);
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))
return -EPERM;
vt_dont_switch = true;
break;
case VT_UNLOCKSWITCH:
if (!capable(CAP_SYS_TTY_CONFIG))
return -EPERM;
vt_dont_switch = false;
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:
return ret;
}
void reset_vc(struct vc_data *vc)
{
vc->vc_mode = KD_TEXT;
vt_reset_unicode(vc->vc_num);
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;
console_lock();
vc = vc_con->d;
if (vc) {
/* FIXME: review tty ref counting */
tty = vc->port.tty;
/*
* SAK should also work in all raw modes and reset
* them properly.
*/
if (tty)
__do_SAK(tty);
reset_vc(vc);
}
console_unlock();
}
#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(struct vc_data *vc, 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, 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, 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);
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);
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,
unsigned int cmd, unsigned long arg)
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
void __user *up = (void __user *)arg;
int perm;
int ret = 0;
/*
* 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;
switch (cmd) {
/*
* these need special handlers for incompatible data structures
*/
case PIO_FONTX:
case GIO_FONTX:
ret = compat_fontx_ioctl(vc, cmd, up, perm, &op);
break;
case KDFONTOP:
ret = compat_kdfontop_ioctl(up, perm, &op, vc);
break;
case PIO_UNIMAP:
case GIO_UNIMAP:
ret = compat_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;
}
return ret;
fallback:
return vt_ioctl(tty, 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;
console_lock();
/* Graphics mode - up to X */
if (disable_vt_switch) {
console_unlock();
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. */
console_unlock();
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.
*/
console_unlock();
return -EIO;
}
console_unlock();
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)
{
console_lock();
disable_vt_switch = !do_switch;
console_unlock();
}
EXPORT_SYMBOL(pm_set_vt_switch);
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