@@ -218,11 +218,9 @@ struct ipv6_pinfo {
#if defined(__BIG_ENDIAN_BITFIELD)
/* Packed in 16bits. */
__s16 mcast_hops:9;
- __u16 __unused_2:6,
- mc_loop:1;
+ __u16 __unused_2:7,
#else
- __u16 mc_loop:1,
- __unused_2:6;
+ __u16 __unused_2:7;
__s16 mcast_hops:9;
#endif
int ucast_oif;
@@ -283,6 +281,18 @@ struct ipv6_pinfo {
struct inet6_cork cork;
};
+/* We currently use available bits from inet_sk(sk)->inet_flags,
+ * this could change in the future.
+ */
+#define inet6_test_bit(nr, sk) \
+ test_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
+#define inet6_set_bit(nr, sk) \
+ set_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
+#define inet6_clear_bit(nr, sk) \
+ clear_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags)
+#define inet6_assign_bit(nr, sk, val) \
+ assign_bit(INET_FLAGS_##nr, &inet_sk(sk)->inet_flags, val)
+
/* WARNING: don't change the layout of the members in {raw,udp,tcp}6_sock! */
struct raw6_sock {
/* inet_sock has to be the first member of raw6_sock */
@@ -268,6 +268,7 @@ enum {
INET_FLAGS_NODEFRAG = 17,
INET_FLAGS_BIND_ADDRESS_NO_PORT = 18,
INET_FLAGS_DEFER_CONNECT = 19,
+ INET_FLAGS_MC6_LOOP = 20,
};
/* cmsg flags for inet */
@@ -2239,7 +2239,7 @@ static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
}
}
-bool sk_mc_loop(struct sock *sk);
+bool sk_mc_loop(const struct sock *sk);
static inline bool sk_can_gso(const struct sock *sk)
{
@@ -759,7 +759,7 @@ static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
return ret;
}
-bool sk_mc_loop(struct sock *sk)
+bool sk_mc_loop(const struct sock *sk)
{
if (dev_recursion_level())
return false;
@@ -771,7 +771,7 @@ bool sk_mc_loop(struct sock *sk)
return inet_test_bit(MC_LOOP, sk);
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
- return inet6_sk(sk)->mc_loop;
+ return inet6_test_bit(MC6_LOOP, sk);
#endif
}
WARN_ON_ONCE(1);
@@ -217,7 +217,7 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol,
inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
np->hop_limit = -1;
np->mcast_hops = IPV6_DEFAULT_MCASTHOPS;
- np->mc_loop = 1;
+ inet6_set_bit(MC6_LOOP, sk);
np->mc_all = 1;
np->pmtudisc = IPV6_PMTUDISC_WANT;
np->repflow = net->ipv6.sysctl.flowlabel_reflect & FLOWLABEL_REFLECT_ESTABLISHED;
@@ -424,6 +424,13 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
return -EINVAL;
WRITE_ONCE(np->hop_limit, val);
return 0;
+ case IPV6_MULTICAST_LOOP:
+ if (optlen < sizeof(int))
+ return -EINVAL;
+ if (val != valbool)
+ return -EINVAL;
+ inet6_assign_bit(MC6_LOOP, sk, valbool);
+ return 0;
}
if (needs_rtnl)
rtnl_lock();
@@ -755,15 +762,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
retv = 0;
break;
- case IPV6_MULTICAST_LOOP:
- if (optlen < sizeof(int))
- goto e_inval;
- if (val != valbool)
- goto e_inval;
- np->mc_loop = valbool;
- retv = 0;
- break;
-
case IPV6_UNICAST_IF:
{
struct net_device *dev = NULL;
@@ -1367,7 +1365,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
}
case IPV6_MULTICAST_LOOP:
- val = np->mc_loop;
+ val = inet6_test_bit(MC6_LOOP, sk);
break;
case IPV6_MULTICAST_IF:
@@ -1996,7 +1996,7 @@ static int __net_init ndisc_net_init(struct net *net)
np = inet6_sk(sk);
np->hop_limit = 255;
/* Do not loopback ndisc messages */
- np->mc_loop = 0;
+ inet6_clear_bit(MC6_LOOP, sk);
return 0;
}
@@ -1298,17 +1298,13 @@ static void set_sock_size(struct sock *sk, int mode, int val)
static void set_mcast_loop(struct sock *sk, u_char loop)
{
/* setsockopt(sock, SOL_IP, IP_MULTICAST_LOOP, &loop, sizeof(loop)); */
- lock_sock(sk);
inet_assign_bit(MC_LOOP, sk, loop);
#ifdef CONFIG_IP_VS_IPV6
- if (sk->sk_family == AF_INET6) {
- struct ipv6_pinfo *np = inet6_sk(sk);
-
+ if (READ_ONCE(sk->sk_family) == AF_INET6) {
/* IPV6_MULTICAST_LOOP */
- np->mc_loop = loop ? 1 : 0;
+ inet6_assign_bit(MC6_LOOP, sk, loop);
}
#endif
- release_sock(sk);
}
/*
Add inet6_{test|set|clear|assign}_bit() helpers. Note that I am using bits from inet->inet_flags, this might change in the future if we need more flags. While solving data-races accessing np->mc_loop, this patch also allows to implement lockless accesses to np->mcast_hops in the following patch. Also constify sk_mc_loop() argument. Signed-off-by: Eric Dumazet <edumazet@google.com> --- include/linux/ipv6.h | 18 ++++++++++++++---- include/net/inet_sock.h | 1 + include/net/sock.h | 2 +- net/core/sock.c | 4 ++-- net/ipv6/af_inet6.c | 2 +- net/ipv6/ipv6_sockglue.c | 18 ++++++++---------- net/ipv6/ndisc.c | 2 +- net/netfilter/ipvs/ip_vs_sync.c | 8 ++------ 8 files changed, 30 insertions(+), 25 deletions(-)