From 83cd5eb654b320c1972254f243531f3f3cebcccf Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 12 Sep 2023 16:02:10 +0000 Subject: 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: Eric Dumazet Reviewed-by: David Ahern Signed-off-by: David S. Miller --- include/linux/ipv6.h | 3 +-- include/net/inet_sock.h | 1 + net/ipv6/ip6_output.c | 3 +-- net/ipv6/ipv6_sockglue.c | 13 ++++++------- 4 files changed, 9 insertions(+), 11 deletions(-) diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index e62413371ea4..f288a35f157f 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -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; diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 5d61c7dc6577..befee0f66c05 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -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 */ diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 8851fe5d45a0..f87d8491d7e2 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -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; } diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index ec10b45c49c1..c22a492e0536 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -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 @@ done: 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: -- cgit