patch "Revert "usbtmc: convert to devm_kzalloc"" added to usb-next

patch "Revert "usbtmc: convert to devm_kzalloc"" added to usb-next

[gregkh]

This is a note to let you know that I've just added the patch titled

    Revert "usbtmc: convert to devm_kzalloc"

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


>From ab21b63e8aedfc73565dd9cdd51eb338341177cb Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Wed, 28 Sep 2016 11:48:44 +0200
Subject: Revert "usbtmc: convert to devm_kzalloc"

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@linux-mips.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable <stable@vger.kernel.org>  # 3.12+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 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 da4f2509f567..a6c1fae7d52a 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -141,6 +141,7 @@ 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)
@@ -1379,7 +1380,7 @@ 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)
 		return -ENOMEM;
 
-- 
2.10.0