[3.16.y-ckt stable] Patch "USB: serial: Destroy serial_minors IDR on module exit" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    USB: serial: Destroy serial_minors IDR on module exit

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt16.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 063fd5d5f09aa5dfe69bc15a395f48d0e8d49dad Mon Sep 17 00:00:00 2001
From: Johannes Thumshirn <jthumshirn at suse.de>
Date: Wed, 8 Jul 2015 17:26:37 +0200
Subject: USB: serial: Destroy serial_minors IDR on module exit

commit d23f47d4927fd2f61b3a754d83c7bcec215b5cfe upstream.

Destroy serial_minors IDR on module exit, reclaiming the allocated memory.

This was detected by the following semantic patch (written by Luis
Rodriguez <mcgrof at suse.com>)

<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@

module_init(init);

@ defines_module_exit @
identifier exit;
@@

module_exit(exit);

@ declares_idr depends on defines_module_init && defines_module_exit @
identifier idr;
@@

DEFINE_IDR(idr);

@ on_exit_calls_destroy depends on declares_idr && defines_module_exit @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 idr_destroy(&idr);
 ...
}

@ missing_module_idr_destroy depends on declares_idr && defines_module_exit && !on_exit_calls_destroy @
identifier declares_idr.idr, defines_module_exit.exit;
@@

exit(void)
{
 ...
 +idr_destroy(&idr);
}
</SmPL>

Signed-off-by: Johannes Thumshirn <jthumshirn at suse.de>
Signed-off-by: Johan Hovold <johan at kernel.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/serial/usb-serial.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 19842370a07f..6fbfc8fc2f5d 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -1290,6 +1290,7 @@ static void __exit usb_serial_exit(void)
 	tty_unregister_driver(usb_serial_tty_driver);
 	put_tty_driver(usb_serial_tty_driver);
 	bus_unregister(&usb_serial_bus_type);
+	idr_destroy(&serial_minors);
 }