[PATCH 5.19 028/717] can: kvaser_usb: Fix use of uninitialized completion

Greg Kroah-Hartman
2022-10-22T07:36:57Z

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit cd7f30e174d09a02ca2afa5ef093fb0f0352e0d8 upstream.

flush_comp is initialized when CMD_FLUSH_QUEUE is sent to the device and
completed when the device sends CMD_FLUSH_QUEUE_RESP.

This causes completion of uninitialized completion if the device sends
CMD_FLUSH_QUEUE_RESP before CMD_FLUSH_QUEUE is ever sent (e.g. as a
response to a flush by a previously bound driver, or a misbehaving
device).

Fix that by initializing flush_comp in kvaser_usb_init_one() like the
other completions.

This issue is only triggerable after RX URBs have been set up, i.e. the
interface has been opened at least once.

Cc: stable@vger.kernel.org
Fixes: aec5fb2268b7 ("can: kvaser_usb: Add support for Kvaser USB hydra family")
Tested-by: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Link: https://lore.kernel.org/all/20221010150829.199676-3-extja@kvaser.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c | 1 +
drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
@@ -712,6 +712,7 @@ static int kvaser_usb_init_one(struct kv
init_usb_anchor(&priv->tx_submitted);
init_completion(&priv->start_comp);
init_completion(&priv->stop_comp);
+ init_completion(&priv->flush_comp);
priv->can.ctrlmode_supported = 0;

priv->dev = dev;
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c
@@ -1914,7 +1914,7 @@ static int kvaser_usb_hydra_flush_queue(
{
int err;

- init_completion(&priv->flush_comp);
+ reinit_completion(&priv->flush_comp);

err = kvaser_usb_hydra_send_simple_cmd(priv->dev, CMD_FLUSH_QUEUE,
priv->channel);