[PATCH 3.12 63/72] ipv6: some ipv6 statistic counters failed to disable bh

From: Jiri Slaby
Date: Fri Apr 18 2014 - 05:39:04 EST


From: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

[ Upstream commit 43a43b6040165f7b40b5b489fe61a4cb7f8c4980 ]

After commit c15b1ccadb323ea ("ipv6: move DAD and addrconf_verify
processing to workqueue") some counters are now updated in process context
and thus need to disable bh before doing so, otherwise deadlocks can
happen on 32-bit archs. Fabio Estevam noticed this while while mounting
a NFS volume on an ARM board.

As a compensation for missing this I looked after the other *_STATS_BH
and found three other calls which need updating:

1) icmp6_send: ip6_fragment -> icmpv6_send -> icmp6_send (error handling)
2) ip6_push_pending_frames: rawv6_sendmsg -> rawv6_push_pending_frames -> ...
(only in case of icmp protocol with raw sockets in error handling)
3) ping6_v6_sendmsg (error handling)

Fixes: c15b1ccadb323ea ("ipv6: move DAD and addrconf_verify processing to workqueue")
Reported-by: Fabio Estevam <festevam@xxxxxxxxx>
Tested-by: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Signed-off-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
net/ipv6/icmp.c | 2 +-
net/ipv6/ip6_output.c | 4 ++--
net/ipv6/mcast.c | 11 ++++++-----
net/ipv6/ping.c | 4 ++--
4 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index eef8d945b362..e2c9ff840f63 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -516,7 +516,7 @@ static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
np->tclass, NULL, &fl6, (struct rt6_info *)dst,
MSG_DONTWAIT, np->dontfrag);
if (err) {
- ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTERRORS);
+ ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTERRORS);
ip6_flush_pending_frames(sk);
} else {
err = icmpv6_push_pending_frames(sk, &fl6, &tmp_hdr,
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 49f85d49cdb4..516e136f15ca 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1535,8 +1535,8 @@ int ip6_push_pending_frames(struct sock *sk)
if (proto == IPPROTO_ICMPV6) {
struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));

- ICMP6MSGOUT_INC_STATS_BH(net, idev, icmp6_hdr(skb)->icmp6_type);
- ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
+ ICMP6MSGOUT_INC_STATS(net, idev, icmp6_hdr(skb)->icmp6_type);
+ ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
}

err = ip6_local_out(skb);
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index d18f9f903db6..d81abd5ba767 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1620,11 +1620,12 @@ static void mld_sendpack(struct sk_buff *skb)
dst_output);
out:
if (!err) {
- ICMP6MSGOUT_INC_STATS_BH(net, idev, ICMPV6_MLD2_REPORT);
- ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
- IP6_UPD_PO_STATS_BH(net, idev, IPSTATS_MIB_OUTMCAST, payload_len);
- } else
- IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_OUTDISCARDS);
+ ICMP6MSGOUT_INC_STATS(net, idev, ICMPV6_MLD2_REPORT);
+ ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
+ IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, payload_len);
+ } else {
+ IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
+ }

rcu_read_unlock();
return;
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index 7856e962a3e6..6acab0bce9d8 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -182,8 +182,8 @@ int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
MSG_DONTWAIT, np->dontfrag);

if (err) {
- ICMP6_INC_STATS_BH(sock_net(sk), rt->rt6i_idev,
- ICMP6_MIB_OUTERRORS);
+ ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
+ ICMP6_MIB_OUTERRORS);
ip6_flush_pending_frames(sk);
} else {
err = icmpv6_push_pending_frames(sk, &fl6,
--
1.9.2

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