From: Colin Ian King <colin.king@canonical.com>
Date: Fri, 18 Aug 2017 12:11:50 +0100
Subject: [PATCH] nfp: fix infinite loop on umapping cleanup
References: bnc#1060662
Patch-mainline: 4.12.10
Git-commit: eac2c68d663effb077210218788952b5a0c1f60e
[ Upstream commit eac2c68d663effb077210218788952b5a0c1f60e ]
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: 4c3523623dc0 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 82bd6b0935f1..fd4a785431ac 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -881,8 +881,7 @@ 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);
--
2.14.2