The gs_usb driver handles USB devices with more than 1 CAN channel. The RX path for all channels share the same bulk endpoint (the transmitted bulk data encodes the channel number). These per-device resources are allocated and submitted by the first opened channel.
During this allocation, the resources are either released immediately in case of a failure or the URBs are anchored. All anchored URBs are finally killed with gs_usb_disconnect().
Currently, gs_can_open() returns with an error if the allocation of a URB or a buffer fails. However, if usb_submit_urb() fails, the driver continues with the URBs submitted so far, even if no URBs were successfully submitted.
Treat every error as fatal and free all allocated resources immediately.
Switch to goto-style error handling, to prepare the driver for more per-device resource allocation.
Cc: stable@vger.kernel.org Cc: John Whittington git@jbrengineering.co.uk Link: https://lore.kernel.org/all/20230716-gs_usb-fix-time-stamp-counter-v1-1-9017... Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de --- drivers/net/can/usb/gs_usb.c | 31 ++++++++++++++++++++++--------- 1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c index d476c2884008..85b7b59c8426 100644 --- a/drivers/net/can/usb/gs_usb.c +++ b/drivers/net/can/usb/gs_usb.c @@ -833,6 +833,7 @@ static int gs_can_open(struct net_device *netdev) .mode = cpu_to_le32(GS_CAN_MODE_START), }; struct gs_host_frame *hf; + struct urb *urb = NULL; u32 ctrlmode; u32 flags = 0; int rc, i; @@ -856,13 +857,14 @@ static int gs_can_open(struct net_device *netdev)
if (!parent->active_channels) { for (i = 0; i < GS_MAX_RX_URBS; i++) { - struct urb *urb; u8 *buf;
/* alloc rx urb */ urb = usb_alloc_urb(0, GFP_KERNEL); - if (!urb) - return -ENOMEM; + if (!urb) { + rc = -ENOMEM; + goto out_usb_kill_anchored_urbs; + }
/* alloc rx buffer */ buf = kmalloc(dev->parent->hf_size_rx, @@ -870,8 +872,8 @@ static int gs_can_open(struct net_device *netdev) if (!buf) { netdev_err(netdev, "No memory left for USB buffer\n"); - usb_free_urb(urb); - return -ENOMEM; + rc = -ENOMEM; + goto out_usb_free_urb; }
/* fill, anchor, and submit rx urb */ @@ -894,9 +896,7 @@ static int gs_can_open(struct net_device *netdev) netdev_err(netdev, "usb_submit failed (err=%d)\n", rc);
- usb_unanchor_urb(urb); - usb_free_urb(urb); - break; + goto out_usb_unanchor_urb; }
/* Drop reference, @@ -945,7 +945,8 @@ static int gs_can_open(struct net_device *netdev) if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP) gs_usb_timestamp_stop(dev); dev->can.state = CAN_STATE_STOPPED; - return rc; + + goto out_usb_kill_anchored_urbs; }
parent->active_channels++; @@ -953,6 +954,18 @@ static int gs_can_open(struct net_device *netdev) netif_start_queue(netdev);
return 0; + +out_usb_unanchor_urb: + usb_unanchor_urb(urb); +out_usb_free_urb: + usb_free_urb(urb); +out_usb_kill_anchored_urbs: + if (!parent->active_channels) + usb_kill_anchored_urbs(&dev->tx_submitted); + + close_candev(netdev); + + return rc; }
static int gs_usb_get_state(const struct net_device *netdev,