diff options
Diffstat (limited to 'drivers/tty/vt/vt_ioctl.c')
| -rw-r--r-- | drivers/tty/vt/vt_ioctl.c | 1322 |
1 files changed, 1322 insertions, 0 deletions
diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c new file mode 100644 index 000000000..b10b86e2c --- /dev/null +++ b/drivers/tty/vt/vt_ioctl.c @@ -0,0 +1,1322 @@ +// 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 + * @event: argument to ioctl (the event) + * + * 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 + * @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) + +/* + * 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 + * + * Called with the console lock held. + */ +static int vt_kdsetmode(struct vc_data *vc, unsigned long mode) +{ + switch (mode) { + case KD_GRAPHICS: + break; + case KD_TEXT0: + case KD_TEXT1: + mode = KD_TEXT; + fallthrough; + case KD_TEXT: + break; + default: + return -EINVAL; + } + + if (vc->vc_mode == mode) + return 0; + + vc->vc_mode = mode; + if (vc->vc_num != fg_console) + return 0; + + /* explicitly blank/unblank the screen if switching modes */ + if (mode == KD_TEXT) + do_unblank_screen(1); + else + do_blank_screen(1); + + return 0; +} + +static int vt_k_ioctl(struct tty_struct *tty, unsigned int cmd, + unsigned long arg, bool perm) +{ + struct vc_data *vc = tty->driver_data; + void __user *up = (void __user *)arg; + unsigned int console = vc->vc_num; + int ret; + + switch (cmd) { + 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. + */ + return put_user(KB_101, (char __user *)arg); + + /* + * 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) + return -EINVAL; + + return ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0; + + case KDENABIO: + case KDDISABIO: + return ksys_ioperm(GPFIRST, GPNUM, + (cmd == KDENABIO)) ? -ENXIO : 0; +#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))) + return -EFAULT; + + ret = kbd_rate(&kbrep); + if (ret) + return ret; + if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat))) + return -EFAULT; + break; + } + + case KDSETMODE: + if (!perm) + return -EPERM; + + console_lock(); + ret = vt_kdsetmode(vc, arg); + console_unlock(); + return ret; + + case KDGETMODE: + return put_user(vc->vc_mode, (int __user *)arg); + + case KDMAPDISP: + case KDUNMAPDISP: + /* + * these work like a combination of mmap and KDENABIO. + * this could be easily finished. + */ + return -EINVAL; + + case KDSKBMODE: + if (!perm) + return -EPERM; + ret = vt_do_kdskbmode(console, arg); + if (ret) + return ret; + tty_ldisc_flush(tty); + break; + + case KDGKBMODE: + return put_user(vt_do_kdgkbmode(console), (int __user *)arg); + + /* this could be folded into KDSKBMODE, but for compatibility + reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */ + case KDSKBMETA: + return vt_do_kdskbmeta(console, arg); + + case KDGKBMETA: + /* FIXME: should review whether this is worth locking */ + return put_user(vt_do_kdgkbmeta(console), (int __user *)arg); + + case KDGETKEYCODE: + case KDSETKEYCODE: + if(!capable(CAP_SYS_TTY_CONFIG)) + perm = 0; + return vt_do_kbkeycode_ioctl(cmd, up, perm); + + case KDGKBENT: + case KDSKBENT: + return vt_do_kdsk_ioctl(cmd, up, perm, console); + + case KDGKBSENT: + case KDSKBSENT: + return vt_do_kdgkb_ioctl(cmd, up, perm); + + /* 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: + return vt_do_diacrit(cmd, up, perm); + + /* 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: + return vt_do_kdskled(console, cmd, arg, perm); + + /* + * 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) + return -EINVAL; + + 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 KDFONTOP: { + struct console_font_op op; + + if (copy_from_user(&op, up, sizeof(op))) + return -EFAULT; + if (!perm && op.op != KD_FONT_OP_GET) + return -EPERM; + ret = con_font_op(vc, &op); + if (ret) + return ret; + if (copy_to_user(up, &op, sizeof(op))) + return -EFAULT; + break; + } + + default: + return -ENOIOCTLCMD; + } + + return 0; +} + +static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, + bool 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; +} + +static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up, + bool perm) +{ + switch (cmd) { + case PIO_CMAP: + if (!perm) + return -EPERM; + return con_set_cmap(up); + + case GIO_CMAP: + return con_get_cmap(up); + + case PIO_SCRNMAP: + if (!perm) + return -EPERM; + return con_set_trans_old(up); + + case GIO_SCRNMAP: + return con_get_trans_old(up); + + case PIO_UNISCRNMAP: + if (!perm) + return -EPERM; + return con_set_trans_new(up); + + case GIO_UNISCRNMAP: + return con_get_trans_new(up); + + case PIO_UNIMAPCLR: + if (!perm) + return -EPERM; + con_clear_unimap(vc); + break; + + case PIO_UNIMAP: + case GIO_UNIMAP: + return do_unimap_ioctl(cmd, up, perm, vc); + + default: + return -ENOIOCTLCMD; + } + + return 0; +} + +static int vt_reldisp(struct vc_data *vc, unsigned int swtch) +{ + int newvt, ret; + + if (vc->vt_mode.mode != VT_PROCESS) + return -EINVAL; + + /* Switched-to response */ + if (vc->vt_newvt < 0) { + /* If it's just an ACK, ignore it */ + return swtch == VT_ACKACQ ? 0 : -EINVAL; + } + + /* Switching-from response */ + if (swtch == 0) { + /* Switch disallowed, so forget we were trying to do it. */ + vc->vt_newvt = -1; + return 0; + } + + /* The current vt has been released, so complete the switch. */ + newvt = vc->vt_newvt; + vc->vt_newvt = -1; + ret = vc_allocate(newvt); + if (ret) + return ret; + + /* + * 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); + + return 0; +} + +static int vt_setactivate(struct vt_setactivate __user *sa) +{ + struct vt_setactivate vsa; + struct vc_data *nvc; + int ret; + + if (copy_from_user(&vsa, sa, sizeof(vsa))) + return -EFAULT; + if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES) + return -ENXIO; + + vsa.console--; + vsa.console = array_index_nospec(vsa.console, MAX_NR_CONSOLES); + console_lock(); + ret = vc_allocate(vsa.console); + if (ret) { + console_unlock(); + return ret; + } + + /* + * 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(); + + /* Commence switch and lock */ + /* Review set_console locks */ + set_console(vsa.console); + + 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); + } +} + +static int vt_resizex(struct vc_data *vc, struct vt_consize __user *cs) +{ + struct vt_consize v; + int i; + + if (copy_from_user(&v, cs, 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_cell_height = vcp->vc_cell_height; + + if (v.v_vlin) + vcp->vc_scan_lines = v.v_vlin; + if (v.v_clin) + vcp->vc_cell_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_cell_height = save_cell_height; + console_unlock(); + return ret; + } + } + console_unlock(); + } + + 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, + unsigned int cmd, unsigned long arg) +{ + struct vc_data *vc = tty->driver_data; + void __user *up = (void __user *)arg; + int i, perm; + int ret; + + /* + * 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; + + ret = vt_k_ioctl(tty, cmd, arg, perm); + if (ret != -ENOIOCTLCMD) + return ret; + + ret = vt_io_ioctl(vc, cmd, up, perm); + if (ret != -ENOIOCTLCMD) + return ret; + + switch (cmd) { + case TIOCLINUX: + return tioclinux(tty, arg); + case VT_SETMODE: + { + struct vt_mode tmp; + + if (!perm) + return -EPERM; + if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) + return -EFAULT; + if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) + return -EINVAL; + + 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) + return -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)) + return -EFAULT; + + 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(); + return put_user(state, &vtstat->v_state); + } + + /* + * 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(); + i = i < MAX_NR_CONSOLES ? (i+1) : -1; + return put_user(i, (int __user *)arg); + + /* + * 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) + return -ENXIO; + + arg--; + arg = array_index_nospec(arg, MAX_NR_CONSOLES); + console_lock(); + ret = vc_allocate(arg); + console_unlock(); + if (ret) + return ret; + set_console(arg); + break; + + case VT_SETACTIVATE: + if (!perm) + return -EPERM; + + return vt_setactivate(up); + + /* + * wait until the specified VT has been activated + */ + case VT_WAITACTIVE: + if (!perm) + return -EPERM; + if (arg == 0 || arg > MAX_NR_CONSOLES) + return -ENXIO; + return vt_waitactive(arg); + + /* + * 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(); + ret = vt_reldisp(vc, arg); + console_unlock(); + + return ret; + + + /* + * Disallocate memory associated to VT (but leave VT1) + */ + case VT_DISALLOCATE: + if (arg > MAX_NR_CONSOLES) + return -ENXIO; + + if (arg == 0) + vt_disallocate_all(); + else + return 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)) + return -EFAULT; + + 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: + if (!perm) + return -EPERM; + + return vt_resizex(vc, up); + + 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: + return put_user(vc->vc_hi_font_mask, + (unsigned short __user *)arg); + case VT_WAITEVENT: + return vt_event_wait_ioctl((struct vt_event __user *)arg); + default: + return -ENOIOCTLCMD; + } + + return 0; +} + +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_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 = compat_ptr(arg); + int perm; + + /* + * 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 KDFONTOP: + return compat_kdfontop_ioctl(up, perm, &op, vc); + + case PIO_UNIMAP: + case GIO_UNIMAP: + return compat_unimap_ioctl(cmd, up, perm, vc); + + /* + * 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: + return vt_ioctl(tty, cmd, arg); + + /* + * the rest has a compatible data structure behind arg, + * but we have to convert it to a proper 64 bit pointer. + */ + default: + return vt_ioctl(tty, cmd, (unsigned long)up); + } +} + + +#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); |