linux-kernel - [PATCH 3.10 06/41] cpuidle: Check the result of cpuidle_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 for Android: free password hash cracker in your pocket

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

Date:	Fri, 11 Apr 2014 09:09:37 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, Daniel Fu <danifu@...dia.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
	Mark Brown <broonie@...nel.org>
Subject: [PATCH 3.10 06/41] cpuidle: Check the result of cpuidle_get_driver() against NULL

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

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

From: Daniel Fu <danifu@...dia.com>

commit 3b9c10e98021e1f92e6f8c7ce1778b86ba68db10 upstream.

If the current CPU has no cpuidle driver, drv will be NULL in
cpuidle_driver_ref().  Check if that is the case before trying
to bump up the driver's refcount to prevent the kernel from
crashing.

[rjw: Subject and changelog]
Signed-off-by: Daniel Fu <danifu@...dia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
Cc: Mark Brown <broonie@...nel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/cpuidle/driver.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -251,7 +251,8 @@ struct cpuidle_driver *cpuidle_driver_re
 	spin_lock(&cpuidle_driver_lock);

 	drv = cpuidle_get_driver();
-	drv->refcnt++;
+	if (drv)
+		drv->refcnt++;

 	spin_unlock(&cpuidle_driver_lock);
 	return drv;

--
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/