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; Patches currently in stable-queue which might be from gvalkov@xxxxxx are queue-4.9/ipheth-fix-eoverflow-in-ipheth_rcvbulk_callback.patch