4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Colin Ian King <colin.king@xxxxxxxxxxxxx> [ 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@xxxxxxxxxxxxx> Acked-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- 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 *sk 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);