From: Lothar Waßmann <LW@KARO-electronics.de>
Date: Thu, 22 Nov 2012 09:11:25 +0000 (+0100)
Subject: USB: chipidea: fix use after free bug
X-Git-Tag: v3.7.2~94
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8af66623ab9c6d0c8b1517d578f7f3ad1e323cc9;p=thirdparty%2Fkernel%2Fstable.git

USB: chipidea: fix use after free bug

commit 98c35534420d3147553bd3071a5fc63cd56de5b1 upstream.

The pointer to a platform_device struct must not be dereferenced after
the device has been unregistered.

This bug produces a crash when unloading the ci13xxx kernel module
compiled with CONFIG_PAGE_POISONING enabled.

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index f69d029b46071..b726c49f96196 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -385,8 +385,9 @@ EXPORT_SYMBOL_GPL(ci13xxx_add_device);
 
 void ci13xxx_remove_device(struct platform_device *pdev)
 {
+	int id = pdev->id;
 	platform_device_unregister(pdev);
-	ida_simple_remove(&ci_ida, pdev->id);
+	ida_simple_remove(&ci_ida, id);
 }
 EXPORT_SYMBOL_GPL(ci13xxx_remove_device);