1 // SPDX-License-Identifier: GPL-2.0
5  *  Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
6  *  Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
7  *  Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
8  *  Some code moved for less code duplication - Andi Kleen - Mar 1997
9  *  Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
50 	 * while we're checking whether it's in-use.  in vt_in_use()
54 	return vc && kref_read(&vc->port.kref) > 1;  in vt_in_use()
77  * ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
123 		if (!(ve->event.event & event))  in vt_event_post()
125 		ve->event.event = event;  in vt_event_post()
126 		/* kernel view is consoles 0..n-1, user space view is  in vt_event_post()
128 		ve->event.oldev = old + 1;  in vt_event_post()
129 		ve->event.newev = new + 1;  in vt_event_post()
131 		ve->done = 1;  in vt_event_post()
142 	INIT_LIST_HEAD(&vw->list);  in __vt_event_queue()
143 	vw->done = 0;  in __vt_event_queue()
146 	list_add(&vw->list, &vt_events);  in __vt_event_queue()
153 	wait_event_interruptible(vt_event_waitqueue, vw->done);  in __vt_event_wait()
162 	list_del(&vw->list);  in __vt_event_dequeue()
167  *	vt_event_wait		-	wait for an event
171  *	structure. On return the structure has wv->done set to 1 for success
183  *	vt_event_wait_ioctl	-	event ioctl handler
194 		return -EFAULT;  in vt_event_wait_ioctl()
197 		return -EINVAL;  in vt_event_wait_ioctl()
203 			return -EFAULT;  in vt_event_wait_ioctl()
206 	return -EINTR;  in vt_event_wait_ioctl()
210  *	vt_waitactive	-	active console wait
230 			return -EINTR;  in vt_waitactive()
241 #define GPNUM (GPLAST - GPFIRST + 1)
244  * currently, setting the mode from KD_TEXT to KD_GRAPHICS doesn't do a whole
248  * restore their engine state. --BenH
252 static int vt_kdsetmode(struct vc_data *vc, unsigned long mode)  in vt_kdsetmode()  argument
254 	switch (mode) {  in vt_kdsetmode()
259 		mode = KD_TEXT;  in vt_kdsetmode()
264 		return -EINVAL;  in vt_kdsetmode()
267 	if (vc->vc_mode == mode)  in vt_kdsetmode()
270 	vc->vc_mode = mode;  in vt_kdsetmode()
271 	if (vc->vc_num != fg_console)  in vt_kdsetmode()
275 	if (mode == KD_TEXT)  in vt_kdsetmode()
286 	struct vc_data *vc = tty->driver_data;  in vt_k_ioctl()
288 	unsigned int console = vc->vc_num;  in vt_k_ioctl()
294 			return -EPERM;  in vt_k_ioctl()
297 		 * the platform-dependent CLOCK_TICK_RATE between 2.6.12  in vt_k_ioctl()
308 			return -EPERM;  in vt_k_ioctl()
346 			return -EINVAL;  in vt_k_ioctl()
348 		return ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;  in vt_k_ioctl()
353 				  (cmd == KDENABIO)) ? -ENXIO : 0;  in vt_k_ioctl()
362 		if (!capable(CAP_SYS_TTY_CONFIG))  in vt_k_ioctl()
363 			return -EPERM;  in vt_k_ioctl()
366 			return -EFAULT;  in vt_k_ioctl()
372 			return -EFAULT;  in vt_k_ioctl()
378 			return -EPERM;  in vt_k_ioctl()
386 		return put_user(vc->vc_mode, (int __user *)arg);  in vt_k_ioctl()
394 		return -EINVAL;  in vt_k_ioctl()
398 			return -EPERM;  in vt_k_ioctl()
419 		if(!capable(CAP_SYS_TTY_CONFIG))  in vt_k_ioctl()
440 	/* don't use them - they will go away without warning */  in vt_k_ioctl()
455 		if (!perm || !capable(CAP_KILL))  in vt_k_ioctl()
456 			return -EPERM;  in vt_k_ioctl()
458 			return -EINVAL;  in vt_k_ioctl()
471 			return -EFAULT;  in vt_k_ioctl()
473 			return -EPERM;  in vt_k_ioctl()
478 			return -EFAULT;  in vt_k_ioctl()
483 		return -ENOIOCTLCMD;  in vt_k_ioctl()
495 		return -EFAULT;  in do_unimap_ioctl()
499 			return -EPERM;  in do_unimap_ioctl()
502 		if (!perm && fg_console != vc->vc_num)  in do_unimap_ioctl()
503 			return -EPERM;  in do_unimap_ioctl()
504 		return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct),  in do_unimap_ioctl()
516 			return -EPERM;  in vt_io_ioctl()
524 			return -EPERM;  in vt_io_ioctl()
532 			return -EPERM;  in vt_io_ioctl()
540 			return -EPERM;  in vt_io_ioctl()
549 		return -ENOIOCTLCMD;  in vt_io_ioctl()
559 	if (vc->vt_mode.mode != VT_PROCESS)  in vt_reldisp()
560 		return -EINVAL;  in vt_reldisp()
562 	/* Switched-to response */  in vt_reldisp()
563 	if (vc->vt_newvt < 0) {  in vt_reldisp()
565 		return swtch == VT_ACKACQ ? 0 : -EINVAL;  in vt_reldisp()
568 	/* Switching-from response */  in vt_reldisp()
571 		vc->vt_newvt = -1;  in vt_reldisp()
576 	newvt = vc->vt_newvt;  in vt_reldisp()
577 	vc->vt_newvt = -1;  in vt_reldisp()
598 		return -EFAULT;  in vt_setactivate()
600 		return -ENXIO;  in vt_setactivate()
603 	vsa.console--;  in vt_setactivate()
616 	nvc->vt_mode = vsa.mode;  in vt_setactivate()
617 	nvc->vt_mode.frsig = 0;  in vt_setactivate()
618 	put_pid(nvc->vt_pid);  in vt_setactivate()
619 	nvc->vt_pid = get_pid(task_pid(current));  in vt_setactivate()
637 		ret = -EBUSY;  in vt_disallocate()
643 		tty_port_put(&vc->port);  in vt_disallocate()
664 			tty_port_put(&vc[i]->port);  in vt_disallocate_all()
674 		return -EFAULT;  in vt_resizex()
678 		v.v_vlin = vc->vc_scan_lines;  in vt_resizex()
684 				return -EINVAL;  in vt_resizex()
693 				return -EINVAL;  in vt_resizex()
699 		return -EINVAL;  in vt_resizex()
710 			int save_scan_lines = vcp->vc_scan_lines;  in vt_resizex()
711 			int save_cell_height = vcp->vc_cell_height;  in vt_resizex()
714 				vcp->vc_scan_lines = v.v_vlin;  in vt_resizex()
716 				vcp->vc_cell_height = v.v_clin;  in vt_resizex()
717 			vcp->vc_resize_user = 1;  in vt_resizex()
720 				vcp->vc_scan_lines = save_scan_lines;  in vt_resizex()
721 				vcp->vc_cell_height = save_cell_height;  in vt_resizex()
733  * We handle the console-specific ioctl's here.  We allow the
739 	struct vc_data *vc = tty->driver_data;  in vt_ioctl()
749 	if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))  in vt_ioctl()
753 	if (ret != -ENOIOCTLCMD)  in vt_ioctl()
757 	if (ret != -ENOIOCTLCMD)  in vt_ioctl()
768 			return -EPERM;  in vt_ioctl()
770 			return -EFAULT;  in vt_ioctl()
771 		if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS)  in vt_ioctl()
772 			return -EINVAL;  in vt_ioctl()
775 		vc->vt_mode = tmp;  in vt_ioctl()
777 		vc->vt_mode.frsig = 0;  in vt_ioctl()
778 		put_pid(vc->vt_pid);  in vt_ioctl()
779 		vc->vt_pid = get_pid(task_pid(current));  in vt_ioctl()
780 		/* no switch is required -- saw@shade.msu.ru */  in vt_ioctl()
781 		vc->vt_newvt = -1;  in vt_ioctl()
792 		memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));  in vt_ioctl()
797 			return -EFAULT;  in vt_ioctl()
811 		if (put_user(fg_console + 1, &vtstat->v_active))  in vt_ioctl()
812 			return -EFAULT;  in vt_ioctl()
821 		return put_user(state, &vtstat->v_state);  in vt_ioctl()
825 	 * Returns the first available (non-opened) console.  in vt_ioctl()
833 		i = i < MAX_NR_CONSOLES ? (i+1) : -1;  in vt_ioctl()
843 			return -EPERM;  in vt_ioctl()
845 			return -ENXIO;  in vt_ioctl()
847 		arg--;  in vt_ioctl()
858 			return -EPERM;  in vt_ioctl()
867 			return -EPERM;  in vt_ioctl()
869 			return -ENXIO;  in vt_ioctl()
878 	 *	0:	pending switch-from not OK  in vt_ioctl()
879 	 *	1:	pending switch-from OK  in vt_ioctl()
880 	 *	2:	completed switch-to OK  in vt_ioctl()
884 			return -EPERM;  in vt_ioctl()
898 			return -ENXIO;  in vt_ioctl()
903 			return vt_disallocate(--arg);  in vt_ioctl()
913 			return -EPERM;  in vt_ioctl()
914 		if (get_user(ll, &vtsizes->v_rows) ||  in vt_ioctl()
915 		    get_user(cc, &vtsizes->v_cols))  in vt_ioctl()
916 			return -EFAULT;  in vt_ioctl()
923 				vc->vc_resize_user = 1;  in vt_ioctl()
934 			return -EPERM;  in vt_ioctl()
939 		if (!capable(CAP_SYS_TTY_CONFIG))  in vt_ioctl()
940 			return -EPERM;  in vt_ioctl()
944 		if (!capable(CAP_SYS_TTY_CONFIG))  in vt_ioctl()
945 			return -EPERM;  in vt_ioctl()
949 		return put_user(vc->vc_hi_font_mask,  in vt_ioctl()
954 		return -ENOIOCTLCMD;  in vt_ioctl()
962 	vc->vc_mode = KD_TEXT;  in reset_vc()
963 	vt_reset_unicode(vc->vc_num);  in reset_vc()
964 	vc->vt_mode.mode = VT_AUTO;  in reset_vc()
965 	vc->vt_mode.waitv = 0;  in reset_vc()
966 	vc->vt_mode.relsig = 0;  in reset_vc()
967 	vc->vt_mode.acqsig = 0;  in reset_vc()
968 	vc->vt_mode.frsig = 0;  in reset_vc()
969 	put_pid(vc->vt_pid);  in reset_vc()
970 	vc->vt_pid = NULL;  in reset_vc()
971 	vc->vt_newvt = -1;  in reset_vc()
983 	vc = vc_con->d;  in vc_SAK()
986 		tty = vc->port.tty;  in vc_SAK()
1015 		return -EFAULT;  in compat_kdfontop_ioctl()
1016 	if (!perm && op->op != KD_FONT_OP_GET)  in compat_kdfontop_ioctl()
1017 		return -EPERM;  in compat_kdfontop_ioctl()
1018 	op->data = compat_ptr(((struct compat_console_font_op *)op)->data);  in compat_kdfontop_ioctl()
1022 	((struct compat_console_font_op *)op)->data = (unsigned long)op->data;  in compat_kdfontop_ioctl()
1024 		return -EFAULT;  in compat_kdfontop_ioctl()
1041 		return -EFAULT;  in compat_unimap_ioctl()
1046 			return -EPERM;  in compat_unimap_ioctl()
1049 		if (!perm && fg_console != vc->vc_num)  in compat_unimap_ioctl()
1050 			return -EPERM;  in compat_unimap_ioctl()
1051 		return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);  in compat_unimap_ioctl()
1059 	struct vc_data *vc = tty->driver_data;  in vt_compat_ioctl()
1069 	if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))  in vt_compat_ioctl()
1135 	 * KD_TEXT mode or vice versa, which means we need to blank or  in complete_change_console()
1138 	old_vc_mode = vc_cons[fg_console].d->vc_mode;  in complete_change_console()
1151 	if (old_vc_mode != vc->vc_mode) {  in complete_change_console()
1152 		if (vc->vc_mode == KD_TEXT)  in complete_change_console()
1163 	if (vc->vt_mode.mode == VT_PROCESS) {  in complete_change_console()
1165 		 * Send the signal as privileged - kill_pid() will  in complete_change_console()
1169 		if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {  in complete_change_console()
1173 		 * to KD_TEXT mode. I'm not sure if this is strictly correct  in complete_change_console()
1181 			if (old_vc_mode != vc->vc_mode) {  in complete_change_console()
1182 				if (vc->vc_mode == KD_TEXT)  in complete_change_console()
1193 	vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num);  in complete_change_console()
1198  * Performs the front-end of a vt switch
1204 	if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)  in change_console()
1208 	 * If this vt is in process mode, then we need to handshake with  in change_console()
1214 	 * If it doesn't, we reset this vt to auto mode and continue.  in change_console()
1219 	 * the user waits just the right amount of time :-) and revert the  in change_console()
1223 	if (vc->vt_mode.mode == VT_PROCESS) {  in change_console()
1225 		 * Send the signal as privileged - kill_pid() will  in change_console()
1232 		vc->vt_newvt = new_vc->vc_num;  in change_console()
1233 		if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {  in change_console()
1245 		 * to KD_TEXT mode. I'm not sure if this is strictly correct  in change_console()
1259 	 * Ignore all switches in KD_GRAPHICS+VT_AUTO mode  in change_console()
1261 	if (vc->vc_mode == KD_GRAPHICS)  in change_console()
1276 	/* Graphics mode - up to X */  in vt_move_to_console()
1287 		return -ENOSPC;  in vt_move_to_console()
1297 		return -EIO;  in vt_move_to_console()
1302 		return -EINTR;  in vt_move_to_console()