net: add __rcu annotation to sk_filter

Add __rcu annotation to :
        (struct sock)->sk_filter

And use appropriate rcu primitives to reduce sparse warnings if
CONFIG_SPARSE_RCU_POINTER=y

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 7 insertions, 7 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 73a4f9702a65..c7a736228ca2 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -301,7 +301,7 @@ struct sock {
         const struct cred       *sk_peer_cred;
         long                    sk_rcvtimeo;
         long                    sk_sndtimeo;
-        struct sk_filter        *sk_filter;
+        struct sk_filter __rcu  *sk_filter;
         void                    *sk_protinfo;
         struct timer_list       sk_timer;
         ktime_t                 sk_stamp;
diff --git a/net/core/filter.c b/net/core/filter.c
index 7adf50352918..7beaec36b541 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -89,8 +89,8 @@ int sk_filter(struct sock *sk, struct sk_buff *skb)
         rcu_read_lock_bh();
         filter = rcu_dereference_bh(sk->sk_filter);
         if (filter) {
-                unsigned int pkt_len = sk_run_filter(skb, filter->insns,
-                                filter->len);
+                unsigned int pkt_len = sk_run_filter(skb, filter->insns, filter->len);
+
                 err = pkt_len ? pskb_trim(skb, pkt_len) : -EPERM;
         }
         rcu_read_unlock_bh();
diff --git a/net/core/sock.c b/net/core/sock.c
index 11db43632df8..3eed5424e659 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1225,7 +1225,7 @@ struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
                 sock_reset_flag(newsk, SOCK_DONE);
                 skb_queue_head_init(&newsk->sk_error_queue);
 
-                filter = newsk->sk_filter;
+                filter = rcu_dereference_protected(newsk->sk_filter, 1);
                 if (filter != NULL)
                         sk_filter_charge(newsk, filter);
 
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index b3f7e8cf18ac..28cb2d733a3c 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1413,7 +1413,7 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
                 }
         }
 
-        if (sk->sk_filter) {
+        if (rcu_dereference_raw(sk->sk_filter)) {
                 if (udp_lib_checksum_complete(skb))
                         goto drop;
         }
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 45e6efb7f171..86c39526ba5e 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -373,7 +373,7 @@ void raw6_icmp_error(struct sk_buff *skb, int nexthdr,
 
 static inline int rawv6_rcv_skb(struct sock * sk, struct sk_buff * skb)
 {
-        if ((raw6_sk(sk)->checksum || sk->sk_filter) &&
+        if ((raw6_sk(sk)->checksum || rcu_dereference_raw(sk->sk_filter)) &&
             skb_checksum_complete(skb)) {
                 atomic_inc(&sk->sk_drops);
                 kfree_skb(skb);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index c84dad432114..91def93bec85 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -527,7 +527,7 @@ int udpv6_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
                 }
         }
 
-        if (sk->sk_filter) {
+        if (rcu_dereference_raw(sk->sk_filter)) {
                 if (udp_lib_checksum_complete(skb))
                         goto drop;
         }