netdev - [PATCH 3/4] net/irda: Use barrier to set task state

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]

Message-Id: <1362499747-4262-4-git-send-email-peter@hurleysoftware.com>
Date:	Tue,  5 Mar 2013 11:09:06 -0500
From:	Peter Hurley <peter@...leysoftware.com>
To:	David Miller <davem@...emloft.net>,
	Samuel Ortiz <samuel@...tiz.org>
Cc:	Sasha Levin <sasha.levin@...cle.com>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	netdev@...r.kernel.org, Jiri Slaby <jslaby@...e.cz>,
	linux-kernel@...r.kernel.org,
	Peter Hurley <peter@...leysoftware.com>
Subject: [PATCH 3/4] net/irda: Use barrier to set task state

Without a memory and compiler barrier, the task state change
can migrate relative to the condition testing in a blocking loop.
However, the task state change must be visible across all cpus
prior to testing those conditions. Failing to do this can result
in the familiar 'lost wakeup' and this task will hang until killed.

Signed-off-by: Peter Hurley <peter@...leysoftware.com>
---
 net/irda/ircomm/ircomm_tty.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/irda/ircomm/ircomm_tty.c b/net/irda/ircomm/ircomm_tty.c
index d282bbe..522543d 100644
--- a/net/irda/ircomm/ircomm_tty.c
+++ b/net/irda/ircomm/ircomm_tty.c
@@ -324,7 +324,7 @@ static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
 		if (tty->termios.c_cflag & CBAUD)
 			tty_port_raise_dtr_rts(port);
 
-		current->state = TASK_INTERRUPTIBLE;
+		set_current_state(TASK_INTERRUPTIBLE);
 
 		if (tty_hung_up_p(filp) ||
 		    !test_bit(ASYNCB_INITIALIZED, &port->flags)) {
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html