nfp: fix infinite loop on umapping cleanup

The while loop that performs the dma page unmapping never decrements
index counter f and hence loops forever. Fix this with a pre-decrement
on f.

Detected by CoverityScan, CID#1357309 ("Infinite loop")

Fixes: 4c3523623d ("net: add driver for Netronome NFP4000/NFP6000 NIC VFs")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Colin Ian King 2017-08-18 12:11:50 +01:00 committed by David S. Miller
parent acc8b31665
commit eac2c68d66

View File

@ -908,8 +908,7 @@ static int nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
return NETDEV_TX_OK;
err_unmap:
--f;
while (f >= 0) {
while (--f >= 0) {
frag = &skb_shinfo(skb)->frags[f];
dma_unmap_page(dp->dev, tx_ring->txbufs[wr_idx].dma_addr,
skb_frag_size(frag), DMA_TO_DEVICE);