| From 194ad3abffceb393e46707f127ac59ddfab96cb1 Mon Sep 17 00:00:00 2001 |
| From: Wen Yang <wenyang@linux.alibaba.com> |
| Date: Sun, 24 Nov 2019 22:22:36 +0800 |
| Subject: [PATCH] usb: roles: fix a potential use after free |
| |
| commit 1848a543191ae32e558bb0a5974ae7c38ebd86fc upstream. |
| |
| Free the sw structure only after we are done using it. |
| This patch just moves the put_device() down a bit to avoid the |
| use after free. |
| |
| Fixes: 5c54fcac9a9d ("usb: roles: Take care of driver module reference counting") |
| Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> |
| Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> |
| Reviewed-by: Peter Chen <peter.chen@nxp.com> |
| Cc: stable <stable@vger.kernel.org> |
| Cc: Hans de Goede <hdegoede@redhat.com> |
| Cc: Chunfeng Yun <chunfeng.yun@mediatek.com> |
| Cc: Suzuki K Poulose <suzuki.poulose@arm.com> |
| Cc: linux-usb@vger.kernel.org |
| Cc: linux-kernel@vger.kernel.org |
| Link: https://lore.kernel.org/r/20191124142236.25671-1-wenyang@linux.alibaba.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c |
| index f45d8df5cfb8..44a4af292f3c 100644 |
| --- a/drivers/usb/roles/class.c |
| +++ b/drivers/usb/roles/class.c |
| @@ -144,8 +144,8 @@ EXPORT_SYMBOL_GPL(usb_role_switch_get); |
| void usb_role_switch_put(struct usb_role_switch *sw) |
| { |
| if (!IS_ERR_OR_NULL(sw)) { |
| - put_device(&sw->dev); |
| module_put(sw->dev.parent->driver->owner); |
| + put_device(&sw->dev); |
| } |
| } |
| EXPORT_SYMBOL_GPL(usb_role_switch_put); |
| -- |
| 2.7.4 |
| |
