From: Anssi Hannula <anssi.hannula@xxxxxxxxxx> kvaser_usb uses completions to signal when a response event is received for outgoing commands. However, it uses init_completion() to reinitialize the start_comp and stop_comp completions before sending the start/stop commands. In case the device sends the corresponding response just before the actual command is sent, complete() may be called concurrently with init_completion() which is not safe. This might be triggerable even with a properly functioning device by stopping the interface (CMD_STOP_CHIP) just after it goes bus-off (which also causes the driver to send CMD_STOP_CHIP when restart-ms is off), but that was not tested. Fix the issue by using reinit_completion() instead. Cc: stable@xxxxxxxxxxxxxxx Fixes: 080f40a6fa28 ("can: kvaser_usb: Add support for Kvaser CAN/USB devices") Tested-by: Jimmy Assarsson <extja@xxxxxxxxxx> Signed-off-by: Anssi Hannula <anssi.hannula@xxxxxxxxxx> Signed-off-by: Jimmy Assarsson <extja@xxxxxxxxxx> --- Changes in v3: - Rebased on 1d5eeda23f36 ("can: kvaser_usb: advertise timestamping capabilities and add ioctl support") - Add stable to CC - Add S-o-b Changes in v2: - Rebased on b3b6df2c56d8 ("can: kvaser_usb: kvaser_usb_leaf: fix bittiming limits") drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c | 4 ++-- drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c index 3dcd35979e6f..3abfaa77e893 100644 --- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c +++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c @@ -1875,7 +1875,7 @@ static int kvaser_usb_hydra_start_chip(struct kvaser_usb_net_priv *priv) { int err; - init_completion(&priv->start_comp); + reinit_completion(&priv->start_comp); err = kvaser_usb_hydra_send_simple_cmd(priv->dev, CMD_START_CHIP_REQ, priv->channel); @@ -1893,7 +1893,7 @@ static int kvaser_usb_hydra_stop_chip(struct kvaser_usb_net_priv *priv) { int err; - init_completion(&priv->stop_comp); + reinit_completion(&priv->stop_comp); /* Make sure we do not report invalid BUS_OFF from CMD_CHIP_STATE_EVENT * see comment in kvaser_usb_hydra_update_state() diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c index 8e11cda85624..9683bc5e8257 100644 --- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c +++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c @@ -1320,7 +1320,7 @@ static int kvaser_usb_leaf_start_chip(struct kvaser_usb_net_priv *priv) { int err; - init_completion(&priv->start_comp); + reinit_completion(&priv->start_comp); err = kvaser_usb_leaf_send_simple_cmd(priv->dev, CMD_START_CHIP, priv->channel); @@ -1338,7 +1338,7 @@ static int kvaser_usb_leaf_stop_chip(struct kvaser_usb_net_priv *priv) { int err; - init_completion(&priv->stop_comp); + reinit_completion(&priv->stop_comp); err = kvaser_usb_leaf_send_simple_cmd(priv->dev, CMD_STOP_CHIP, priv->channel); -- 2.37.3