ipv6: lockless IPV6_RECVERR_RFC4884 implementation

Move np->recverr_rfc4884 to an atomic flag to fix data-races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 9cc278b5e4f42ce097e57ecd95a50479a947fd82..0d2b0a1b2daeaee51a03624adab5a385cc852cc7 100644 (file)
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -256,7 +256,6 @@ struct ipv6_pinfo {
                                autoflowlabel:1,
                                autoflowlabel_set:1,
                                mc_all:1,
-                               recverr_rfc4884:1,
                                rtalert_isolate:1;
        __u8                    min_hopcount;
        __u8                    tclass;

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index b5a9dca92fb45425c032bdf08bfa88cad77926b8..8cf1f7b442348bef83cc3d9648521a01667efae7 100644 (file)
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -269,6 +269,7 @@ enum {
        INET_FLAGS_BIND_ADDRESS_NO_PORT = 18,
        INET_FLAGS_DEFER_CONNECT = 19,
        INET_FLAGS_MC6_LOOP     = 20,
+       INET_FLAGS_RECVERR6_RFC4884 = 21,
 };
 
 /* cmsg flags for inet */

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 41ebc4e574734456357169e883c3d13e42fa66b2..e81892814935fb3934fbf0e6f9defc702ec29152 100644 (file)
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -332,7 +332,7 @@ void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 
        __skb_pull(skb, payload - skb->data);
 
-       if (inet6_sk(sk)->recverr_rfc4884)
+       if (inet6_test_bit(RECVERR6_RFC4884, sk))
                ipv6_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
 
        skb_reset_transport_header(skb);

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index bbc8a009e05d3de49868e1ccf469a12bc31b8e22..b65e73ac2ccdee79aa293948d3ba9853966e1e2d 100644 (file)
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -462,6 +462,13 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
                 */
                WRITE_ONCE(np->min_hopcount, val);
                return 0;
+       case IPV6_RECVERR_RFC4884:
+               if (optlen < sizeof(int))
+                       return -EINVAL;
+               if (val < 0 || val > 1)
+                       return -EINVAL;
+               inet6_assign_bit(RECVERR6_RFC4884, sk, valbool);
+               return 0;
        }
        if (needs_rtnl)
                rtnl_lock();
@@ -974,14 +981,6 @@ done:
                np->rxopt.bits.recvfragsize = valbool;
                retv = 0;
                break;
-       case IPV6_RECVERR_RFC4884:
-               if (optlen < sizeof(int))
-                       goto e_inval;
-               if (val < 0 || val > 1)
-                       goto e_inval;
-               np->recverr_rfc4884 = valbool;
-               retv = 0;
-               break;
        }
 
 unlock:
@@ -1462,7 +1461,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
                break;
 
        case IPV6_RECVERR_RFC4884:
-               val = np->recverr_rfc4884;
+               val = inet6_test_bit(RECVERR6_RFC4884, sk);
                break;
 
        default: