Commit 83cd5eb6 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6: lockless IPV6_ROUTER_ALERT_ISOLATE implementation 



Reads from np->rtalert_isolate are racy.

Move this flag to inet->inet_flags to fix data-races.

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 3cccda8d

include/linux/ipv6.h

+1 −2
Original line number Diff line number Diff line
@@ -246,11 +246,10 @@ struct ipv6_pinfo { 
	__u16			sndflow:1,

				pmtudisc:3,

				padding:1,	/* 1 bit hole */

				srcprefs:3,	/* 001: prefer temporary address

				srcprefs:3;	/* 001: prefer temporary address

						 * 010: prefer public address

						 * 100: prefer care-of address

						 */

				rtalert_isolate:1;

	__u8			min_hopcount;

	__u8			tclass;

	__be32			rcv_flowinfo;

include/net/inet_sock.h

+1 −0
Original line number Diff line number Diff line
@@ -276,6 +276,7 @@ enum { 
	INET_FLAGS_DONTFRAG	= 25,

	INET_FLAGS_RECVERR6	= 26,

	INET_FLAGS_REPFLOW	= 27,

	INET_FLAGS_RTALERT_ISOLATE = 28,

};



/* cmsg flags for inet */

net/ipv6/ip6_output.c

+1 −2
Original line number Diff line number Diff line
@@ -368,9 +368,8 @@ static int ip6_call_ra_chain(struct sk_buff *skb, int sel) 
		if (sk && ra->sel == sel &&

		    (!sk->sk_bound_dev_if ||

		     sk->sk_bound_dev_if == skb->dev->ifindex)) {

			struct ipv6_pinfo *np = inet6_sk(sk);



			if (np && np->rtalert_isolate &&

			if (inet6_test_bit(RTALERT_ISOLATE, sk) &&

			    !net_eq(sock_net(sk), dev_net(skb->dev))) {

				continue;

			}

net/ipv6/ipv6_sockglue.c

+6 −7
Original line number Diff line number Diff line
@@ -488,6 +488,11 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, 
		if (!val)

			skb_errqueue_purge(&sk->sk_error_queue);

		return 0;

	case IPV6_ROUTER_ALERT_ISOLATE:

		if (optlen < sizeof(int))

			return -EINVAL;

		inet6_assign_bit(RTALERT_ISOLATE, sk, valbool);

		return 0;

	}

	if (needs_rtnl)

		rtnl_lock();
@@ -936,12 +941,6 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, 
			goto e_inval;

		retv = ip6_ra_control(sk, val);

		break;

	case IPV6_ROUTER_ALERT_ISOLATE:

		if (optlen < sizeof(int))

			goto e_inval;

		np->rtalert_isolate = valbool;

		retv = 0;

		break;

	case IPV6_MTU_DISCOVER:

		if (optlen < sizeof(int))

			goto e_inval;
@@ -1452,7 +1451,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname, 
		break;



	case IPV6_ROUTER_ALERT_ISOLATE:

		val = np->rtalert_isolate;

		val = inet6_test_bit(RTALERT_ISOLATE, sk);

		break;



	case IPV6_RECVERR_RFC4884: