[PATCH 4.9 06/33] net: ethernet: sun: niu set correct packet size in skb

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Rob Taglang <rob@xxxxxxxxxx>

[ Upstream commit 14224923c3600bae2ac4dcae3bf0c3d4dc2812be ]

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@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/sun/niu.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/sun/niu.c
+++ b/drivers/net/ethernet/sun/niu.c
@@ -3442,7 +3442,7 @@ static int niu_process_rx_pkt(struct nap
 
 		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;
@@ -3452,7 +3452,6 @@ static int niu_process_rx_pkt(struct nap
 					 RCR_ENTRY_PKTBUFSZ_SHIFT];
 
 		off = addr & ~PAGE_MASK;
-		append_size = rcr_size;
 		if (num_rcr == 1) {
 			int ptype;
 
@@ -3465,7 +3464,7 @@ static int niu_process_rx_pkt(struct nap
 			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) {