From: Julian Anastasov <ja@xxxxxx>
ip_vs_dest_hold will be used under RCU lock
while ip_vs_dest_put can be called even after dest
is removed from service, as it happens for conns and
some schedulers.
Signed-off-by: Julian Anastasov <ja@xxxxxx>
Signed-off-by: Simon Horman <horms@xxxxxxxxxxxx>
---
include/net/ip_vs.h | 10 ++++++++++
net/netfilter/ipvs/ip_vs_conn.c | 9 ++-------
net/netfilter/ipvs/ip_vs_ctl.c | 4 ++--
net/netfilter/ipvs/ip_vs_sync.c | 4 ++--
4 files changed, 16 insertions(+), 11 deletions(-)
diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index d91385c..7d3027f 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -1427,6 +1427,16 @@ ip_vs_find_dest(struct net *net, int af, const union nf_inet_addr *daddr,
__u16 protocol, __u32 fwmark, __u32 flags);
extern struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp);
+static inline void ip_vs_dest_hold(struct ip_vs_dest *dest)
+{
+ atomic_inc(&dest->refcnt);
+}
+
+static inline void ip_vs_dest_put(struct ip_vs_dest *dest)
+{
+ smp_mb__before_atomic_dec();
+ atomic_dec(&dest->refcnt);
+}
/*
* IPVS sync daemon data and function prototypes
diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index e3e2b4d..1b29e4a 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -554,7 +554,7 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
return;
/* Increase the refcnt counter of the dest */
- atomic_inc(&dest->refcnt);
+ ip_vs_dest_hold(dest);
conn_flags = atomic_read(&dest->conn_flags);
if (cp->protocol != IPPROTO_UDP)
@@ -700,12 +700,7 @@ static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
dest->flags &= ~IP_VS_DEST_F_OVERLOAD;
}
- /*
- * Simply decrease the refcnt of the dest, because the
- * dest will be either in service's destination list
- * or in the trash.
- */
- atomic_dec(&dest->refcnt);
+ ip_vs_dest_put(dest);
}
static int expire_quiescent_template(struct netns_ipvs *ipvs,
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index d64f800..a4f6388 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -616,7 +616,7 @@ struct ip_vs_dest *ip_vs_find_dest(struct net *net, int af,
if (!dest)
dest = ip_vs_lookup_dest(svc, daddr, port ^ dport);
if (dest)
- atomic_inc(&dest->refcnt);
+ ip_vs_dest_hold(dest);
ip_vs_service_put(svc);
return dest;
}
@@ -1056,7 +1056,7 @@ static void __ip_vs_del_dest(struct net *net, struct ip_vs_dest *dest)
ntohs(dest->port),
atomic_read(&dest->refcnt));
list_add(&dest->n_list, &ipvs->dest_trash);
- atomic_inc(&dest->refcnt);
+ ip_vs_dest_hold(dest);
}
}
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index 44fd10c..6cc3e52 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -861,7 +861,7 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
if (!dest) {
dest = ip_vs_try_bind_dest(cp);
if (dest)
- atomic_dec(&dest->refcnt);
+ ip_vs_dest_put(dest);
}
} else {
/*
@@ -874,7 +874,7 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
cp = ip_vs_conn_new(param, daddr, dport, flags, dest, fwmark);
if (dest)
- atomic_dec(&dest->refcnt);
+ ip_vs_dest_put(dest);
if (!cp) {
if (param->pe_data)
kfree(param->pe_data);
--
1.7.10.4
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
