Commit 9fc3de9c authored by Arthur Taylor's avatar Arthur Taylor Committed by Greg Kroah-Hartman
Browse files

vt: Add virtual console keyboard mode OFF 



virtual console: add keyboard mode OFF

Add a new mode for the virtual console keyboard OFF in which all input
other than shift keys is ignored. Prevents vt input buffers from
overflowing when a program opens but doesn't read from a tty, like X11
using evdev for input.

Signed-off-by: default avatarArthur Taylor <art@ified.ca>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 8e6d3fe1

drivers/tty/vt/keyboard.c

+3 −2
Original line number Diff line number Diff line
@@ -654,7 +654,8 @@ static void k_spec(struct vc_data *vc, unsigned char value, char up_flag) 
	if (value >= ARRAY_SIZE(fn_handler))

		return;

	if ((kbd->kbdmode == VC_RAW ||

	     kbd->kbdmode == VC_MEDIUMRAW) &&

	     kbd->kbdmode == VC_MEDIUMRAW ||

	     kbd->kbdmode == VC_OFF) &&

	     value != KVAL(K_SAK))

		return;		/* SAK is allowed even in raw mode */

	fn_handler[value](vc);
@@ -1295,7 +1296,7 @@ static void kbd_keycode(unsigned int keycode, int down, int hw_raw) 
	if (rc == NOTIFY_STOP)

		return;



	if (raw_mode && type != KT_SPEC && type != KT_SHIFT)

	if ((raw_mode || kbd->kbdmode == VC_OFF) && type != KT_SPEC && type != KT_SHIFT)

		return;



	(*k_handler[type])(vc, keysym & 0xff, !down);

drivers/tty/vt/vt_ioctl.c

+3 −0
Original line number Diff line number Diff line
@@ -688,6 +688,9 @@ int vt_ioctl(struct tty_struct *tty, struct file * file, 
			kbd->kbdmode = VC_UNICODE;

			compute_shiftstate();

			break;

		  case K_OFF:

			kbd->kbdmode = VC_OFF;

			break;

		  default:

			ret = -EINVAL;

			goto out;

include/linux/kbd_kern.h

+2 −1
Original line number Diff line number Diff line
@@ -50,11 +50,12 @@ struct kbd_struct { 
#define VC_CAPSLOCK	2	/* capslock mode */

#define VC_KANALOCK	3	/* kanalock mode */



	unsigned char kbdmode:2;	/* one 2-bit value */

	unsigned char kbdmode:3;	/* one 3-bit value */

#define VC_XLATE	0	/* translate keycodes using keymap */

#define VC_MEDIUMRAW	1	/* medium raw (keycode) mode */

#define VC_RAW		2	/* raw (scancode) mode */

#define VC_UNICODE	3	/* Unicode mode */

#define VC_OFF		4	/* disabled mode */



	unsigned char modeflags:5;

#define VC_APPLIC	0	/* application key mode */

include/linux/kd.h

+1 −0
Original line number Diff line number Diff line
@@ -81,6 +81,7 @@ struct unimapinit { 
#define		K_XLATE		0x01

#define		K_MEDIUMRAW	0x02

#define		K_UNICODE	0x03

#define		K_OFF		0x04

#define KDGKBMODE	0x4B44	/* gets current keyboard mode */

#define KDSKBMODE	0x4B45	/* sets current keyboard mode */

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