linux-kernel - [PATCH 3.12 74/84] Revert "usbtmc: convert to devm

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: <f50798220707b64d67b530dba36a972467c81f23.1476690493.git.jslaby@suse.cz>
Date:   Mon, 17 Oct 2016 09:52:01 +0200
From:   Jiri Slaby <jslaby@...e.cz>
To:     stable@...r.kernel.org
Cc:     linux-kernel@...r.kernel.org,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 3.12 74/84] Revert "usbtmc: convert to devm_kzalloc"

From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

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

===============

commit ab21b63e8aedfc73565dd9cdd51eb338341177cb upstream.

This reverts commit e6c7efdcb76f11b04e3d3f71c8d764ab75c9423b.

Turns out it was totally wrong.  The memory is supposed to be bound to
the kref, as the original code was doing correctly, not the
device/driver binding as the devm_kzalloc() would cause.

This fixes an oops when read would be called after the device was
unbound from the driver.

Reported-by: Ladislav Michl <ladis@...ux-mips.org>
Cc: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
 drivers/usb/class/usbtmc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index c997ee9122bc..72ed4ac2cfad 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -122,6 +122,7 @@ static void usbtmc_delete(struct kref *kref)
 	struct usbtmc_device_data *data = to_usbtmc_data(kref);
 
 	usb_put_dev(data->usb_dev);
+	kfree(data);
 }
 
 static int usbtmc_open(struct inode *inode, struct file *filp)
@@ -1101,7 +1102,7 @@ static int usbtmc_probe(struct usb_interface *intf,
 
 	dev_dbg(&intf->dev, "%s called\n", __func__);
 
-	data = devm_kzalloc(&intf->dev, sizeof(*data), GFP_KERNEL);
+	data = kmalloc(sizeof(*data), GFP_KERNEL);
 	if (!data) {
 		dev_err(&intf->dev, "Unable to allocate kernel memory\n");
 		return -ENOMEM;
-- 
2.10.1