[PATCH] net: ethernet: sun: niu set correct packet size in skb

[Rob Taglang <rob@taglang.io>]

Currently, skb->len and skb->data_len are set to the page size, not the 
packet size. This causes the frame check sequence to not be located at 
the "end" of the packet resulting in ethernet frame check errors. The 
driver does work currently, but stricter kernel facing networking 
solutions like OpenVSwitch will drop these packets as invalid.

These changes set the packet size correctly so that these errors no 
longer occur. The length does not include the frame check sequence, so 
that subtraction was removed.

Tested on Oracle/SUN Multithreaded 10-Gigabit Ethernet Network 
Controller [108e:abcd] and validated in wireshark.

Signed-off-by: Rob Taglang <rob@taglang.io>
---
  drivers/net/ethernet/sun/niu.c | 5 ++---
  1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/sun/niu.c 
b/drivers/net/ethernet/sun/niu.c
index f081de4..88c1247 100644
--- a/drivers/net/ethernet/sun/niu.c
+++ b/drivers/net/ethernet/sun/niu.c
@@ -3443,7 +3443,7 @@ static int niu_process_rx_pkt(struct napi_struct 
*napi, struct niu *np,

  		len = (val & RCR_ENTRY_L2_LEN) >>
  			RCR_ENTRY_L2_LEN_SHIFT;
-		len -= ETH_FCS_LEN;
+		append_size = len + ETH_HLEN + ETH_FCS_LEN;

  		addr = (val & RCR_ENTRY_PKT_BUF_ADDR) <<
  			RCR_ENTRY_PKT_BUF_ADDR_SHIFT;
@@ -3453,7 +3453,6 @@ static int niu_process_rx_pkt(struct napi_struct 
*napi, struct niu *np,
  					 RCR_ENTRY_PKTBUFSZ_SHIFT];

  		off = addr & ~PAGE_MASK;
-		append_size = rcr_size;
  		if (num_rcr == 1) {
  			int ptype;

@@ -3466,7 +3465,7 @@ static int niu_process_rx_pkt(struct napi_struct 
*napi, struct niu *np,
  			else
  				skb_checksum_none_assert(skb);
  		} else if (!(val & RCR_ENTRY_MULTI))
-			append_size = len - skb->len;
+			append_size = append_size - skb->len;

  		niu_rx_skb_append(skb, page, off, append_size, rcr_size);
  		if ((page->index + rp->rbr_block_size) - rcr_size == addr) {