ipheth: fix EOVERFLOW in ipheth_rcvbulk_callback

From: Georgi Valkov
Date: Tue Jul 20 2021 - 05:45:03 EST


ipheth: fix EOVERFLOW in ipheth_rcvbulk_callback
https://github.com/openwrt/openwrt/pull/4084


From dd109ded2b526636fff438d33433ab64ffd21583 Mon Sep 17 00:00:00 2001
From: Georgi Valkov <gvalkov@xxxxxx>
Date: Fri, 16 Apr 2021 20:44:36 +0300
Subject: [PATCH] ipheth: fix EOVERFLOW in ipheth_rcvbulk_callback

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.

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

Signed-off-by: Georgi Valkov <gvalkov@xxxxxx>
---
drivers/net/usb/ipheth.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c
index 207e59e74935..06d9f19ca142 100644
--- a/drivers/net/usb/ipheth.c
+++ b/drivers/net/usb/ipheth.c
@@ -121,7 +121,7 @@ static int ipheth_alloc_urbs(struct ipheth_device *iphone)
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;
@@ -146,7 +146,7 @@ static int ipheth_alloc_urbs(struct ipheth_device *iphone)

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);
@@ -317,7 +317,7 @@ static int ipheth_rx_submit(struct ipheth_device *dev, gfp_t mem_flags)

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;
--
2.31.1