[PATCH] cdc-acm: Destroy acm_minors IDR on module exit

From: Johannes Thumshirn
Date: Wed Jul 08 2015 - 11:25:50 EST


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

This was detected by the following semantic patch (written by Luis Rodriguez
<mcgrof@xxxxxxxx>)
<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@xxxxxxx>
---
drivers/usb/class/cdc-acm.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 519a77b..b30e742 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1944,6 +1944,7 @@ static void __exit acm_exit(void)
usb_deregister(&acm_driver);
tty_unregister_driver(acm_tty_driver);
put_tty_driver(acm_tty_driver);
+ idr_destroy(&acm_minors);
}

module_init(acm_init);
--
2.4.3

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