This is a note to let you know that I've just added the patch titled
spi: fix use-after-free at controller deregistration
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: spi-fix-use-after-free-at-controller-deregistration.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 67f7b2781fafcc0f52464880154b320fea1ae982 Mon Sep 17 00:00:00 2001
From: Johan Hovold johan@kernel.org Date: Mon, 30 Oct 2017 11:35:25 +0100 Subject: spi: fix use-after-free at controller deregistration
From: Johan Hovold johan@kernel.org
commit 67f7b2781fafcc0f52464880154b320fea1ae982 upstream.
The controller is typically freed as part of device_unregister() so store the bus id before deregistration to avoid use-after-free when the id is later released.
Fixes: 9b61e302210e ("spi: Pick spi bus number from Linux idr or spi alias") Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/spi/spi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2245,11 +2245,12 @@ static int __unregister(struct device *d void spi_unregister_controller(struct spi_controller *ctlr) { struct spi_controller *found; + int id = ctlr->bus_num; int dummy;
/* First make sure that this controller was ever added */ mutex_lock(&board_lock); - found = idr_find(&spi_master_idr, ctlr->bus_num); + found = idr_find(&spi_master_idr, id); mutex_unlock(&board_lock); if (found != ctlr) { dev_dbg(&ctlr->dev, @@ -2269,7 +2270,7 @@ void spi_unregister_controller(struct sp device_unregister(&ctlr->dev); /* free bus id */ mutex_lock(&board_lock); - idr_remove(&spi_master_idr, ctlr->bus_num); + idr_remove(&spi_master_idr, id); mutex_unlock(&board_lock); } EXPORT_SYMBOL_GPL(spi_unregister_controller);
Patches currently in stable-queue which might be from johan@kernel.org are
queue-4.14/usb-serial-qcserial-add-pid-vid-for-sierra-wireless-em7355-fw-update.patch queue-4.14/staging-greybus-spilib-fix-use-after-free-after-deregistration.patch queue-4.14/usb-serial-metro-usb-stop-i-o-after-failed-open.patch queue-4.14/usb-serial-change-dbc-debug-device-binding-id.patch queue-4.14/spi-fix-use-after-free-at-controller-deregistration.patch queue-4.14/usb-serial-garmin_gps-fix-i-o-after-failed-probe-and-remove.patch queue-4.14/usb-serial-garmin_gps-fix-memory-leak-on-probe-errors.patch