diff mbox series

[2/7] USB: cdc-acm: fix use-after-free after probe failure

Message ID 20210318155202.22230-3-johan@kernel.org
State Accepted
Commit 4e49bf376c0451ad2eae2592e093659cde12be9a
Headers show
Series None | expand

Commit Message

Johan Hovold March 18, 2021, 3:51 p.m. UTC
If tty-device registration fails the driver would fail to release the
data interface. When the device is later disconnected, the disconnect
callback would still be called for the data interface and would go about
releasing already freed resources.

Fixes: c93d81955005 ("usb: cdc-acm: fix error handling in acm_probe()")
Cc: stable@vger.kernel.org      # 3.9
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/class/cdc-acm.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index d75a78ad464d..dfc2480add91 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1503,6 +1503,11 @@  static int acm_probe(struct usb_interface *intf,
 
 	return 0;
 alloc_fail6:
+	if (!acm->combined_interfaces) {
+		/* Clear driver data so that disconnect() returns early. */
+		usb_set_intfdata(data_interface, NULL);
+		usb_driver_release_interface(&acm_driver, data_interface);
+	}
 	if (acm->country_codes) {
 		device_remove_file(&acm->control->dev,
 				&dev_attr_wCountryCodes);