From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (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 9584A19D08F for ; Sat, 8 Nov 2025 09:01:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762592481; cv=none; b=snEFj1BKr1woMeyToPzeL1wCsNWOwSmBUOWFnDYY7eXK+z2+lEENJQ9UYl4YHumZwMLPpv0KgvVGVYGStiT2HXD80BTt5VN2wr6eHXjyUMp0lIjqpI/BUmJuekHU+zc/s1rPYrFl/9hY8asRo3EgwJHmhlfpqcVRNhffisOePJs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762592481; c=relaxed/simple; bh=7fNx/AX63/lcrl0SzWFf1gLEWkW0J5hkOQiArbLfdHc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=r9u6VTxcYeQbeLtuaj9bOi/mw5SxN4ulDNli+Jw2YkkE8iGKLuLS1/+5Kyq3xUk22mCG09Wju6N3/JFkn3s6GqDEmmHxkPY2vchNBj7OeMR4AU1agj79l4+ruVIXsqu1jyPt90d/mP/BKq3ZFnXuR6CysSi7vpOdtLQj0Mfdv1s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1vHeos-0004vs-1d; Sat, 08 Nov 2025 10:01:14 +0100 Received: from moin.white.stw.pengutronix.de ([2a0a:edc0:0:b01:1d::7b] helo=bjornoya.blackshift.org) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vHeor-007fMD-2g; Sat, 08 Nov 2025 10:01:13 +0100 Received: from hardanger.blackshift.org (unknown [IPv6:2a01:4f8:1c1c:29e9:22:41ff:fe00:1400]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: mkl-all@blackshift.org) by smtp.blackshift.org (Postfix) with ESMTPSA id 28FC949A89D; Sat, 08 Nov 2025 09:01:13 +0000 (UTC) From: Marc Kleine-Budde Date: Sat, 08 Nov 2025 10:01:02 +0100 Subject: [PATCH can 2/3] can: gs_usb: gs_usb_receive_bulk_callback(): check actual_length before accessing header Precedence: bulk X-Mailing-List: linux-can@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20251108-gs_usb-fix-usb-callbacks-v1-2-8a2534a7ea05@pengutronix.de> References: <20251108-gs_usb-fix-usb-callbacks-v1-0-8a2534a7ea05@pengutronix.de> In-Reply-To: <20251108-gs_usb-fix-usb-callbacks-v1-0-8a2534a7ea05@pengutronix.de> To: Vincent Mailhol , Maximilian Schneider , Wolfgang Grandegger Cc: kernel@pengutronix.de, linux-can@vger.kernel.org, linux-kernel@vger.kernel.org, Marc Kleine-Budde X-Mailer: b4 0.15-dev-509f5 X-Developer-Signature: v=1; a=openpgp-sha256; l=2432; i=mkl@pengutronix.de; h=from:subject:message-id; bh=7fNx/AX63/lcrl0SzWFf1gLEWkW0J5hkOQiArbLfdHc=; b=owEBbQGS/pANAwAKAQx0Zd/5kJGcAcsmYgBpDwbTOzrOuARzT/lDlpR+lSbwNflicIZOAXng2 H8nFZjrFciJATMEAAEKAB0WIQSf+wzYr2eoX/wVbPMMdGXf+ZCRnAUCaQ8G0wAKCRAMdGXf+ZCR nKJ3CACtLg7J3tsHLkZGor/lgOHPs24LaLTRcR4lK7lOWSvzMnuDz2Nemg+JWBfgksjM276YXDN 3qqOygXrkEZuySWr7vIhMEU3j8AonJ7j6udm16RaF79Ldv1CwtErZlfPkp9YcS0wS+HlLFIc3KJ AYR4GuV4cSJrW60alJ8eQcTUN4SUULnIEQ7VvACfMzWzvMJoc2xDGxtnP7Zv+SOLIyB6uJD+Cef YNCnFMAnNQofz/EPkaw+KjKCXwq/bli0sUrQAtb+aKY8IDTtZmbUitASwOBjsmnlf21vu3PFO2L 7oeSrXDEoOI9Y40U95jQ9W3MVv961yTqUG8SUXOoXGNomm87 X-Developer-Key: i=mkl@pengutronix.de; a=openpgp; fpr=C1400BA0B3989E6FBC7D5B5C2B5EE211C58AEA54 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-can@vger.kernel.org The driver expects to receive a struct gs_host_frame in gs_usb_receive_bulk_callback(). Use struct_group to describe the header of the struct gs_host_frame and check that we have at least received the header before accessing any members of it. To resubmit the URB, do not dereference the pointer chain "dev->parent->hf_size_rx" but use "parent->hf_size_rx" instead. Since "urb->context" contains "parent", it is always defined, while "dev" is not defined if the URB it too short. Fixes: d08e973a77d1 ("can: gs_usb: Added support for the GS_USB CAN devices") Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/gs_usb.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-) diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c index fa9bab8c89ae..51f8d694104d 100644 --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -262,13 +262,15 @@ struct canfd_quirk { } __packed; struct gs_host_frame { - u32 echo_id; - __le32 can_id; + struct_group(header, + u32 echo_id; + __le32 can_id; - u8 can_dlc; - u8 channel; - u8 flags; - u8 reserved; + u8 can_dlc; + u8 channel; + u8 flags; + u8 reserved; + ); union { DECLARE_FLEX_ARRAY(struct classic_can, classic_can); @@ -576,6 +578,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb) int rc; struct net_device_stats *stats; struct gs_host_frame *hf = urb->transfer_buffer; + unsigned int minimum_length; struct gs_tx_context *txc; struct can_frame *cf; struct canfd_frame *cfd; @@ -594,6 +597,15 @@ static void gs_usb_receive_bulk_callback(struct urb *urb) return; } + minimum_length = sizeof(hf->header); + if (urb->actual_length < minimum_length) { + dev_err_ratelimited(&parent->udev->dev, + "short read (actual_length=%u, minimum_length=%u)\n", + urb->actual_length, minimum_length); + + goto resubmit_urb; + } + /* device reports out of range channel id */ if (hf->channel >= parent->channel_cnt) goto device_detach; @@ -687,7 +699,7 @@ static void gs_usb_receive_bulk_callback(struct urb *urb) resubmit_urb: usb_fill_bulk_urb(urb, parent->udev, parent->pipe_in, - hf, dev->parent->hf_size_rx, + hf, parent->hf_size_rx, gs_usb_receive_bulk_callback, parent); rc = usb_submit_urb(urb, GFP_ATOMIC); -- 2.51.0