[PATCH 4.19 49/86] ipheth: fix EOVERFLOW in ipheth_rcvbulk_callback

From: Greg Kroah-Hartman
Date: Mon Feb 07 2022 - 06:26:05 EST


From: Georgi Valkov <gvalkov@xxxxxx>

commit 63e4b45c82ed1bde979da7052229a4229ce9cabf upstream.

When rx_buf is allocated we need to account for IPHETH_IP_ALIGN,
which reduces the usable size by 2 bytes. Otherwise we have 1512
bytes usable instead of 1514, and if we receive more than 1512
bytes, ipheth_rcvbulk_callback is called with status -EOVERFLOW,
after which the driver malfunctiones and all communication stops.

Resolves ipheth 2-1:4.2: ipheth_rcvbulk_callback: urb status: -75

Fixes: f33d9e2b48a3 ("usbnet: ipheth: fix connectivity with iOS 14")
Signed-off-by: Georgi Valkov <gvalkov@xxxxxx>
Tested-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
Link: https://lore.kernel.org/all/B60B8A4B-92A0-49B3-805D-809A2433B46C@xxxxxx/
Link: https://lore.kernel.org/all/24851bd2769434a5fc24730dce8e8a984c5a4505.1643699778.git.jan.kiszka@xxxxxxxxxxx/
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/usb/ipheth.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/net/usb/ipheth.c
+++ b/drivers/net/usb/ipheth.c
@@ -173,7 +173,7 @@ static int ipheth_alloc_urbs(struct iphe
if (tx_buf == NULL)
goto free_rx_urb;

- rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE,
+ rx_buf = usb_alloc_coherent(iphone->udev, IPHETH_BUF_SIZE + IPHETH_IP_ALIGN,
GFP_KERNEL, &rx_urb->transfer_dma);
if (rx_buf == NULL)
goto free_tx_buf;
@@ -198,7 +198,7 @@ error_nomem:

static void ipheth_free_urbs(struct ipheth_device *iphone)
{
- usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->rx_buf,
+ usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE + IPHETH_IP_ALIGN, iphone->rx_buf,
iphone->rx_urb->transfer_dma);
usb_free_coherent(iphone->udev, IPHETH_BUF_SIZE, iphone->tx_buf,
iphone->tx_urb->transfer_dma);
@@ -371,7 +371,7 @@ static int ipheth_rx_submit(struct iphet

usb_fill_bulk_urb(dev->rx_urb, udev,
usb_rcvbulkpipe(udev, dev->bulk_in),
- dev->rx_buf, IPHETH_BUF_SIZE,
+ dev->rx_buf, IPHETH_BUF_SIZE + IPHETH_IP_ALIGN,
ipheth_rcvbulk_callback,
dev);
dev->rx_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;