Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755256Ab2BSVJP (ORCPT ); Sun, 19 Feb 2012 16:09:15 -0500 Received: from mail.pripojeni.net ([178.22.112.14]:33435 "EHLO smtp.pripojeni.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755115Ab2BSVIv (ORCPT ); Sun, 19 Feb 2012 16:08:51 -0500 From: Jiri Slaby To: gregkh@suse.de Cc: linux-kernel@vger.kernel.org, Sasha Levin , jirislaby@gmail.com Subject: [PATCH 1/1] TTY: fix PTY hangup vs close race Date: Sun, 19 Feb 2012 22:08:43 +0100 Message-Id: <1329685723-14963-1-git-send-email-jslaby@suse.cz> X-Mailer: git-send-email 1.7.9 In-Reply-To: <1329683796.10124.21.camel@lappy> References: <1329683796.10124.21.camel@lappy> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1404 Lines: 39 Commit d3bda5298 (TTY: get rid of BTM around devpts_*) moved devpts_pty_kill out of BTM, but the BTM was not protecting only devpts_pty_kill, but also tty->link. Hence move the function back at this late stage until this gets resolved properly some time later. I was confused by tty_vhangup(tty->link) outside BTM. But inside of tty_vhangup, there is a check for tty == NULL. But we cannot add such a check here. We have to have the tty and free the devpts node... Signed-off-by: Jiri Slaby Reported-by: Sasha Levin --- drivers/tty/pty.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c index fa1bd2e..95037aa 100644 --- a/drivers/tty/pty.c +++ b/drivers/tty/pty.c @@ -54,8 +54,9 @@ static void pty_close(struct tty_struct *tty, struct file *filp) wake_up_interruptible(&tty->link->write_wait); if (tty->driver->subtype == PTY_TYPE_MASTER) { set_bit(TTY_OTHER_CLOSED, &tty->flags); - tty_unlock(); + /* BTM protects tty->link here */ devpts_pty_kill(tty->link); + tty_unlock(); tty_vhangup(tty->link); tty_lock(); } -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/