Commit 1ac13efd authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6: annotate data-races around np->ucast_oif 



np->ucast_oif is read locklessly in some contexts.

Make all accesses to this field lockless, adding appropriate
annotations.

This also makes setsockopt( IPV6_UNICAST_IF ) lockless.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d2f011a0

net/ipv6/datagram.c

+1 −1
Original line number Diff line number Diff line
@@ -62,7 +62,7 @@ static void ip6_datagram_flow_key_init(struct flowi6 *fl6, 
		if (ipv6_addr_is_multicast(&fl6->daddr))

			oif = READ_ONCE(np->mcast_oif);

		else

			oif = np->ucast_oif;

			oif = READ_ONCE(np->ucast_oif);

	}



	fl6->flowi6_oif = oif;

net/ipv6/icmp.c

+2 −2
Original line number Diff line number Diff line
@@ -586,7 +586,7 @@ void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info, 
	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))

		fl6.flowi6_oif = READ_ONCE(np->mcast_oif);

	else if (!fl6.flowi6_oif)

		fl6.flowi6_oif = np->ucast_oif;

		fl6.flowi6_oif = READ_ONCE(np->ucast_oif);



	ipcm6_init_sk(&ipc6, sk);

	ipc6.sockc.mark = mark;
@@ -772,7 +772,7 @@ static enum skb_drop_reason icmpv6_echo_reply(struct sk_buff *skb) 
	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))

		fl6.flowi6_oif = READ_ONCE(np->mcast_oif);

	else if (!fl6.flowi6_oif)

		fl6.flowi6_oif = np->ucast_oif;

		fl6.flowi6_oif = READ_ONCE(np->ucast_oif);



	if (ip6_dst_lookup(net, sk, &dst, &fl6))

		goto out;

net/ipv6/ipv6_sockglue.c

+26 −32
Original line number Diff line number Diff line
@@ -537,6 +537,31 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, 
		}

		WRITE_ONCE(np->mcast_oif, val);

		return 0;

	case IPV6_UNICAST_IF:

	{

		struct net_device *dev;

		int ifindex;



		if (optlen != sizeof(int))

			return -EINVAL;



		ifindex = (__force int)ntohl((__force __be32)val);

		if (!ifindex) {

			WRITE_ONCE(np->ucast_oif, 0);

			return 0;

		}



		dev = dev_get_by_index(net, ifindex);

		if (!dev)

			return -EADDRNOTAVAIL;

		dev_put(dev);



		if (READ_ONCE(sk->sk_bound_dev_if))

			return -EINVAL;



		WRITE_ONCE(np->ucast_oif, ifindex);

		return 0;

	}

	}

	if (needs_rtnl)

		rtnl_lock();
@@ -857,37 +882,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, 
		break;

	}





	case IPV6_UNICAST_IF:

	{

		struct net_device *dev = NULL;

		int ifindex;



		if (optlen != sizeof(int))

			goto e_inval;



		ifindex = (__force int)ntohl((__force __be32)val);

		if (ifindex == 0) {

			np->ucast_oif = 0;

			retv = 0;

			break;

		}



		dev = dev_get_by_index(net, ifindex);

		retv = -EADDRNOTAVAIL;

		if (!dev)

			break;

		dev_put(dev);



		retv = -EINVAL;

		if (sk->sk_bound_dev_if)

			break;



		np->ucast_oif = ifindex;

		retv = 0;

		break;

	}



	case IPV6_ADD_MEMBERSHIP:

	case IPV6_DROP_MEMBERSHIP:

	{
@@ -1369,7 +1363,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname, 
		break;



	case IPV6_UNICAST_IF:

		val = (__force int)htonl((__u32) np->ucast_oif);

		val = (__force int)htonl((__u32) READ_ONCE(np->ucast_oif));

		break;



	case IPV6_MTU_DISCOVER:

net/ipv6/ping.c

+2 −2
Original line number Diff line number Diff line
@@ -109,7 +109,7 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 
	if (!oif && ipv6_addr_is_multicast(daddr))

		oif = READ_ONCE(np->mcast_oif);

	else if (!oif)

		oif = np->ucast_oif;

		oif = READ_ONCE(np->ucast_oif);



	addr_type = ipv6_addr_type(daddr);

	if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
@@ -159,7 +159,7 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 
	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))

		fl6.flowi6_oif = READ_ONCE(np->mcast_oif);

	else if (!fl6.flowi6_oif)

		fl6.flowi6_oif = np->ucast_oif;

		fl6.flowi6_oif = READ_ONCE(np->ucast_oif);



	pfh.icmph.type = user_icmph.icmp6_type;

	pfh.icmph.code = user_icmph.icmp6_code;

net/ipv6/raw.c

+1 −1
Original line number Diff line number Diff line
@@ -878,7 +878,7 @@ static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 
	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))

		fl6.flowi6_oif = READ_ONCE(np->mcast_oif);

	else if (!fl6.flowi6_oif)

		fl6.flowi6_oif = np->ucast_oif;

		fl6.flowi6_oif = READ_ONCE(np->ucast_oif);

	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));



	if (hdrincl)