Patch "staging: greybus: spilib: fix use-after-free after deregistration" has been added to the 4.13-stable tree

This is a note to let you know that I've just added the patch titled

staging: greybus: spilib: fix use-after-free after deregistration

to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
staging-greybus-spilib-fix-use-after-free-after-deregistration.patch
and it can be found in the queue-4.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Johan Hovold <[email protected]>
Date: Sun, 29 Oct 2017 13:01:33 +0100
Subject: staging: greybus: spilib: fix use-after-free after deregistration

From: Johan Hovold <[email protected]>

commit 770b03c2ca4aa44d226cf248f86aa23e546147d0 upstream.

Remove erroneous spi_master_put() after controller deregistration which would access the already freed spi controller.

Note that spi_unregister_master() drops our only controller reference.

---
 drivers/staging/greybus/spilib.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

@@ -544,12 +544,15 @@ int gb_spilib_master_init(struct gb_conn
 
 	return 0;
 
-exit_spi_unregister:
-	spi_unregister_master(master);
 exit_spi_put:
 	spi_master_put(master);
 
 	return ret;
+
+exit_spi_unregister:
+	spi_unregister_master(master);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(gb_spilib_master_init);
 

@@ -558,7 +561,6 @@ void gb_spilib_master_exit(struct gb_con
 	struct spi_master *master = gb_connection_get_data(connection);
 
 	spi_unregister_master(master);
-	spi_master_put(master);
 }
 EXPORT_SYMBOL_GPL(gb_spilib_master_exit);
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.13/usb-serial-qcserial-add-pid-vid-for-sierra-wireless-em7355-fw-update.patch queue-4.13/staging-greybus-spilib-fix-use-after-free-after-deregistration.patch queue-4.13/usb-serial-metro-usb-stop-i-o-after-failed-open.patch queue-4.13/usb-serial-change-dbc-debug-device-binding-id.patch queue-4.13/usb-serial-garmin_gps-fix-i-o-after-failed-probe-and-remove.patch queue-4.13/usb-serial-garmin_gps-fix-memory-leak-on-probe-errors.patch