linux-kernel - [v2.6.34-stable 202/213] futex: Test for pi_mutex on fault in futex_wait_requeue

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:	Wed, 5 Feb 2014 15:02:37 -0500
From:	Paul Gortmaker <paul.gortmaker@...driver.com>
To:	<stable@...r.kernel.org>, <linux-kernel@...r.kernel.org>
CC:	Darren Hart <dvhart@...ux.intel.com>,
	Dave Jones <davej@...hat.com>,
	Dan Carpenter <dan.carpenter@...cle.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Paul Gortmaker <paul.gortmaker@...driver.com>
Subject: [v2.6.34-stable 202/213] futex: Test for pi_mutex on fault in futex_wait_requeue_pi()

From: Darren Hart <dvhart@...ux.intel.com>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit b6070a8d9853eda010a549fa9a09eb8d7269b929 upstream.

If fixup_pi_state_owner() faults, pi_mutex may be NULL. Test
for pi_mutex != NULL before testing the owner against current
and possibly unlocking it.

Signed-off-by: Darren Hart <dvhart@...ux.intel.com>
Cc: Dave Jones <davej@...hat.com>
Cc: Dan Carpenter <dan.carpenter@...cle.com>
Link: http://lkml.kernel.org/r/dc59890338fc413606f04e5c5b131530734dae3d.1342809673.git.dvhart@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@...driver.com>
---
 kernel/futex.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/futex.c b/kernel/futex.c
index d4e7f0ea1f94..0e8043833223 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -2348,7 +2348,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, int fshared,
 	 * fault, unlock the rt_mutex and return the fault to userspace.
 	 */
 	if (ret == -EFAULT) {
-		if (rt_mutex_owner(pi_mutex) == current)
+		if (pi_mutex && rt_mutex_owner(pi_mutex) == current)
 			rt_mutex_unlock(pi_mutex);
 	} else if (ret == -EINTR) {
 		/*
-- 
1.8.5.2

--
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/