linux-kernel - [ 11/56] tty: keyboard.c: Remove locking from vt_get

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

Date:	Thu,  4 Oct 2012 14:15:32 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	alan@...rguk.ukuu.org.uk,
	Christopher Brannon <chris@...-brannons.com>,
	Alan Cox <alan@...ux.intel.com>
Subject: [ 11/56] tty: keyboard.c: Remove locking from vt_get_leds.

3.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Christopher Brannon <chris@...-brannons.com>

commit 157a4b311c45c9aba75a990464d9680867dc8805 upstream.

There are three call sites for this function, and all three
are called within a keyboard handler.
kbd_event_lock is already held within keyboard handlers,
so attempting to lock it in vt_get_leds causes deadlock.

Signed-off-by: Christopher Brannon <chris@...-brannons.com>
Acked-by: Alan Cox <alan@...ux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/tty/vt/keyboard.c |    3 ---
 1 file changed, 3 deletions(-)

--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -1049,13 +1049,10 @@ static int kbd_update_leds_helper(struct
  */
 int vt_get_leds(int console, int flag)
 {
-	unsigned long flags;
 	struct kbd_struct * kbd = kbd_table + console;
 	int ret;
 
-	spin_lock_irqsave(&kbd_event_lock, flags);
 	ret = vc_kbd_led(kbd, flag);
-	spin_unlock_irqrestore(&kbd_event_lock, flags);
 
 	return ret;
 }


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/