From: Li RongQing <roy.qing.li@xxxxxxxxx>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
commit abb6013cca147ad940b0e9fee260d2d9e93b7018 upstream.
when read/write the 64bit data, the correct lock should be hold.
Fixes: 87b6d218f3adb ("tunnel: implement 64 bits statistics")
Cc: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: Li RongQing <roy.qing.li@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
net/ipv6/ip6_tunnel.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index c47708fac826..509fbc805017 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -104,16 +104,25 @@ struct ip6_tnl_net {
static struct net_device_stats *ip6_get_stats(struct net_device *dev)
{
- struct pcpu_tstats sum = { 0 };
+ struct pcpu_tstats tmp, sum = { 0 };
int i;
for_each_possible_cpu(i) {
+ unsigned int start;
const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i);
- sum.rx_packets += tstats->rx_packets;
- sum.rx_bytes += tstats->rx_bytes;
- sum.tx_packets += tstats->tx_packets;
- sum.tx_bytes += tstats->tx_bytes;
+ do {
+ start = u64_stats_fetch_begin_bh(&tstats->syncp);
+ tmp.rx_packets = tstats->rx_packets;
+ tmp.rx_bytes = tstats->rx_bytes;
+ tmp.tx_packets = tstats->tx_packets;
+ tmp.tx_bytes = tstats->tx_bytes;
+ } while (u64_stats_fetch_retry_bh(&tstats->syncp, start));
+
+ sum.rx_packets += tmp.rx_packets;
+ sum.rx_bytes += tmp.rx_bytes;
+ sum.tx_packets += tmp.tx_packets;
+ sum.tx_bytes += tmp.tx_bytes;
}
dev->stats.rx_packets = sum.rx_packets;
dev->stats.rx_bytes = sum.rx_bytes;
@@ -832,8 +841,10 @@ static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
}
tstats = this_cpu_ptr(t->dev->tstats);
+ u64_stats_update_begin(&tstats->syncp);
tstats->rx_packets++;
tstats->rx_bytes += skb->len;
+ u64_stats_update_end(&tstats->syncp);
netif_rx(skb);
--
2.12.0