diff options
| author | Marc Kleine-Budde <mkl@pengutronix.de> | 2025-11-08 10:01:02 +0100 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2025-11-16 17:04:13 +0100 |
| commit | 6fe9f3279f7d2518439a7962c5870c6e9ecbadcf (patch) | |
| tree | 93e77bcf35d6f1a3bfdf6060009a1ac8b804a4f1 | |
| parent | 516a0cd1c03fa266bb67dd87940a209fd4e53ce7 (diff) | |
can: gs_usb: gs_usb_receive_bulk_callback(): check actual_length before accessing header
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")
Link: https://patch.msgid.link/20251114-gs_usb-fix-usb-callbacks-v1-2-a29b42eacada@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
| -rw-r--r-- | drivers/net/can/usb/gs_usb.c | 26 |
1 files 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); |