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

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

[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-testing 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 be merged to the usb-next branch sometime soon,
after it passes testing, and the merge window is open.

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