Messages in this thread Patch in this message | | | From | Kamal Mostafa <> | Subject | [PATCH 3.19.y-ckt 39/56] net: bcmgenet: fix skb_len in bcmgenet_xmit_single() | Date | Tue, 12 Apr 2016 13:58:57 -0700 |
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3.19.8-ckt19 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------
From: Petri Gynther <pgynther@google.com>
commit 7dd399130efb5a454daf24075b7563d197114e39 upstream.
skb_len needs to be skb_headlen(skb) in bcmgenet_xmit_single().
Fragmented skbs can have only Ethernet + IP + TCP headers (14+20+20=54 bytes) in the linear buffer, followed by the rest in fragments. Bumping skb_len to ETH_ZLEN would be incorrect for this case, as it would introduce garbage between TCP header and the fragment data.
This also works with regular/non-fragmented small packets < ETH_ZLEN bytes. Successfully tested this on GENETv3 with 42-byte ARP frames.
For testing, I used: ethtool -K eth0 tx-checksum-ipv4 off ethtool -K eth0 tx-checksum-ipv6 off echo 0 > /proc/sys/net/ipv4/tcp_timestamps
Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file") Signed-off-by: Petri Gynther <pgynther@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/net/ethernet/broadcom/genet/bcmgenet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c index 822b5df..209b572 100644 --- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c +++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c @@ -1110,7 +1110,7 @@ static int bcmgenet_xmit_single(struct net_device *dev, tx_cb_ptr->skb = skb; - skb_len = skb_headlen(skb) < ETH_ZLEN ? ETH_ZLEN : skb_headlen(skb); + skb_len = skb_headlen(skb); mapping = dma_map_single(kdev, skb->data, skb_len, DMA_TO_DEVICE); ret = dma_mapping_error(kdev, mapping); -- 2.7.4
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