linux-kernel - [PATCH] input&tty: Fix the keyboard led light display problem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:   Thu, 14 Oct 2021 16:53:08 +0800
From:   lianzhi chang <changlianzhi@...ontech.com>
To:     linux-kernel@...r.kernel.org
Cc:     linux-input@...r.kernel.org,
        lianzhi chang <changlianzhi@...ontech.com>
Subject: [PATCH] input&tty: Fix the keyboard led light display problem

Switching from the desktop environment to the tty environment,
the state of the keyboard led lights and the state of the keyboard
lock are inconsistent. This is because the attribute kb->kbdmode
of the tty bound in the desktop environment (xorg) is set to
VC_OFF, which causes the ledstate and kb->ledflagstate
values of the bound tty to always be 0, which causes the switch
from the desktop When to the tty environment, the LED light
status is inconsistent with the keyboard lock status.

Signed-off-by: lianzhi chang <changlianzhi@...ontech.com>
---
 drivers/input/input.c     |  7 ++++++-
 drivers/tty/vt/keyboard.c | 30 +++++++++++++++++++++++++++++-
 include/linux/kbd_kern.h  |  2 ++
 3 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/input/input.c b/drivers/input/input.c
index ccaeb2426385..43c09700bf68 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -25,6 +25,7 @@
 #include <linux/rcupdate.h>
 #include "input-compat.h"
 #include "input-poller.h"
+#include <linux/kbd_kern.h>
 
 MODULE_AUTHOR("Vojtech Pavlik <vojtech@...e.cz>");
 MODULE_DESCRIPTION("Input core");
@@ -472,8 +473,12 @@ void input_inject_event(struct input_handle *handle,
 
 		rcu_read_lock();
 		grab = rcu_dereference(dev->grab);
-		if (!grab || grab == handle)
+		if (!grab || grab == handle) {
 			input_handle_event(dev, type, code, value);
+
+			if (type == EV_LED && code < LED_SCROLLL)
+				update_value_ledstate(code, value);
+		}
 		rcu_read_unlock();
 
 		spin_unlock_irqrestore(&dev->event_lock, flags);
diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index c7fbbcdcc346..0240915cdfef 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -1140,6 +1140,31 @@ static unsigned char getledstate(void)
 	return ledstate & 0xff;
 }
 
+void update_value_ledstate(unsigned int flag, unsigned int value)
+{
+	unsigned int bit;
+
+	switch (flag) {
+	case LED_NUML:
+		bit = VC_NUMLOCK;
+		break;
+	case LED_CAPSL:
+		bit = VC_CAPSLOCK;
+		break;
+	case LED_SCROLLL:
+		bit = VC_SCROLLOCK;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return;
+	}
+
+	if (value)
+		ledstate |= BIT(bit);
+	else
+		ledstate &= ~BIT(bit);
+}
+
 void setledstate(struct kbd_struct *kb, unsigned int led)
 {
         unsigned long flags;
@@ -1249,6 +1274,10 @@ static void kbd_bh(struct tasklet_struct *unused)
 {
 	unsigned int leds;
 	unsigned long flags;
+	struct kbd_struct *kb = kbd_table + fg_console;
+
+	if (kb->kbdmode == VC_OFF)
+		return;
 
 	spin_lock_irqsave(&led_lock, flags);
 	leds = getleds();
@@ -1257,7 +1286,6 @@ static void kbd_bh(struct tasklet_struct *unused)
 
 	if (leds != ledstate) {
 		kbd_propagate_led_state(ledstate, leds);
-		ledstate = leds;
 	}
 }
 
diff --git a/include/linux/kbd_kern.h b/include/linux/kbd_kern.h
index c40811d79769..36a3402658e6 100644
--- a/include/linux/kbd_kern.h
+++ b/include/linux/kbd_kern.h
@@ -62,6 +62,8 @@ extern int kbd_init(void);
 
 extern void setledstate(struct kbd_struct *kbd, unsigned int led);
 
+extern void update_value_ledstate(int flag, int value);
+
 extern int do_poke_blanked_console;
 
 extern void (*kbd_ledfunc)(unsigned int led);
-- 
2.20.1