linux-kernel - [PATCH] tty: Remove warning in tty_lock

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 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:	Tue, 30 Dec 2014 07:11:11 -0500
From:	Peter Hurley <peter@...leysoftware.com>
To:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:	Jiri Slaby <jslaby@...e.cz>,
	Dan Carpenter <dan.carpenter@...cle.com>,
	linux-kernel@...r.kernel.org, linux-serial@...r.kernel.org,
	Peter Hurley <peter@...leysoftware.com>
Subject: [PATCH] tty: Remove warning in tty_lock_slave()

Commit 2aff5e2bc62db43e05c814461a08aff0fc2b7fe5 ('tty: Change
tty lock order to master->slave') added a warning which is broken
and unnecessary now that the tty lock has fixed lock subclasses,
added in commit 2febdb632bb96235b94b8fccaf882a78f8f4b2bb
('tty: Preset lock subclass for nested tty locks').

Reported-by: Dan Carpenter <dan.carpenter@...cle.com>
Signed-off-by: Peter Hurley <peter@...leysoftware.com>
---
 drivers/tty/tty_mutex.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/tty/tty_mutex.c b/drivers/tty/tty_mutex.c
index 4486741..a872389 100644
--- a/drivers/tty/tty_mutex.c
+++ b/drivers/tty/tty_mutex.c
@@ -46,12 +46,8 @@ EXPORT_SYMBOL(tty_unlock);
 
 void __lockfunc tty_lock_slave(struct tty_struct *tty)
 {
-	if (tty && tty != tty->link) {
-		WARN_ON(!mutex_is_locked(&tty->link->legacy_mutex) ||
-			!tty->driver->type == TTY_DRIVER_TYPE_PTY ||
-			!tty->driver->type == PTY_TYPE_SLAVE);
+	if (tty && tty != tty->link)
 		tty_lock(tty);
-	}
 }
 
 void __lockfunc tty_unlock_slave(struct tty_struct *tty)
-- 
2.2.1

--
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/