From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 404DC629 for ; Wed, 2 Nov 2022 03:28:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4E162C433C1; Wed, 2 Nov 2022 03:28:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1667359738; bh=pqSnykMIfQxwmzSq2JcY8DwL0vLvZnQpAXlCjQHnWo4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kBUKKxf1f/Q2v5vkFCK64e1gEb5lvc5xTS1OVY3mQYahI+kxwJLWntsjIIysvmf2Y XyWp36iUqMoYfmv7goqpiFbCW8pWXbLoe9wFUB4VM+42UOrPxPqbEDK8Y36vV0Y8rk DoNoYa1/fHtL1Ucd64BrRY6i/QLP8SWdK2hrJaRQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jimmy Assarsson , Anssi Hannula , Marc Kleine-Budde Subject: [PATCH 4.19 26/78] can: kvaser_usb: Fix possible completions during init_completion Date: Wed, 2 Nov 2022 03:34:11 +0100 Message-Id: <20221102022053.760634152@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221102022052.895556444@linuxfoundation.org> References: <20221102022052.895556444@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Anssi Hannula commit 2871edb32f4622c3a25ce4b3977bad9050b91974 upstream. 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. Fixes: 080f40a6fa28 ("can: kvaser_usb: Add support for Kvaser CAN/USB devices") Tested-by: Jimmy Assarsson Signed-off-by: Anssi Hannula Signed-off-by: Jimmy Assarsson Link: https://lore.kernel.org/all/20221010185237.319219-2-extja@kvaser.com Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- 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(-) --- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c +++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_hydra.c @@ -1845,7 +1845,7 @@ static int kvaser_usb_hydra_start_chip(s { 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); @@ -1863,7 +1863,7 @@ static int kvaser_usb_hydra_stop_chip(st { 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() --- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c +++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c @@ -1324,7 +1324,7 @@ static int kvaser_usb_leaf_start_chip(st { 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); @@ -1342,7 +1342,7 @@ static int kvaser_usb_leaf_stop_chip(str { 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);