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ipv6: annotate data-races around np->mcast_oif

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np->mcast_oif is read locklessly in some contexts.

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

This also makes setsockopt( IPV6_MULTICAST_IF ) lockless.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2023-12-08 10:12:43 +00:00 committed by David S. Miller
parent 9a64d4c93e
commit d2f011a0bf
11 changed files with 51 additions and 49 deletions
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2
net/dccp/ipv6.c
View File

@ -669,7 +669,7 @@ discard:
ipv6_pktoptions:
if (!((1 << sk->sk_state) & (DCCPF_CLOSED | DCCPF_LISTEN))) {
if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
np->mcast_oif = inet6_iif(opt_skb);
WRITE_ONCE(np->mcast_oif, inet6_iif(opt_skb));
if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
WRITE_ONCE(np->mcast_hops, ipv6_hdr(opt_skb)->hop_limit);
if (np->rxopt.bits.rxflow || np->rxopt.bits.rxtclass)

4
net/ipv6/datagram.c
View File

@ -60,7 +60,7 @@ static void ip6_datagram_flow_key_init(struct flowi6 *fl6,
if (!oif) {
if (ipv6_addr_is_multicast(&fl6->daddr))
oif = np->mcast_oif;
oif = READ_ONCE(np->mcast_oif);
else
oif = np->ucast_oif;
}
@ -229,7 +229,7 @@ ipv4_connected:
}
if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
WRITE_ONCE(sk->sk_bound_dev_if, np->mcast_oif);
WRITE_ONCE(sk->sk_bound_dev_if, READ_ONCE(np->mcast_oif));
/* Connect to link-local address requires an interface */
if (!sk->sk_bound_dev_if) {

4
net/ipv6/icmp.c
View File

@ -584,7 +584,7 @@ void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
tmp_hdr.icmp6_pointer = htonl(info);
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
fl6.flowi6_oif = np->mcast_oif;
fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
else if (!fl6.flowi6_oif)
fl6.flowi6_oif = np->ucast_oif;
@ -770,7 +770,7 @@ static enum skb_drop_reason icmpv6_echo_reply(struct sk_buff *skb)
np = inet6_sk(sk);
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
fl6.flowi6_oif = np->mcast_oif;
fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
else if (!fl6.flowi6_oif)
fl6.flowi6_oif = np->ucast_oif;

74
net/ipv6/ipv6_sockglue.c
View File

@ -509,6 +509,34 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
if (optlen < sizeof(int))
return -EINVAL;
return ip6_sock_set_addr_preferences(sk, val);
case IPV6_MULTICAST_IF:
if (sk->sk_type == SOCK_STREAM)
return -ENOPROTOOPT;
if (optlen < sizeof(int))
return -EINVAL;
if (val) {
struct net_device *dev;
int bound_dev_if, midx;
rcu_read_lock();
dev = dev_get_by_index_rcu(net, val);
if (!dev) {
rcu_read_unlock();
return -ENODEV;
}
midx = l3mdev_master_ifindex_rcu(dev);
rcu_read_unlock();
bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
if (bound_dev_if &&
bound_dev_if != val &&
(!midx || midx != bound_dev_if))
return -EINVAL;
}
WRITE_ONCE(np->mcast_oif, val);
return 0;
}
if (needs_rtnl)
rtnl_lock();
@ -860,36 +888,6 @@ done:
break;
}
case IPV6_MULTICAST_IF:
if (sk->sk_type == SOCK_STREAM)
break;
if (optlen < sizeof(int))
goto e_inval;
if (val) {
struct net_device *dev;
int midx;
rcu_read_lock();
dev = dev_get_by_index_rcu(net, val);
if (!dev) {
rcu_read_unlock();
retv = -ENODEV;
break;
}
midx = l3mdev_master_ifindex_rcu(dev);
rcu_read_unlock();
if (sk->sk_bound_dev_if &&
sk->sk_bound_dev_if != val &&
(!midx || midx != sk->sk_bound_dev_if))
goto e_inval;
}
np->mcast_oif = val;
retv = 0;
break;
case IPV6_ADD_MEMBERSHIP:
case IPV6_DROP_MEMBERSHIP:
{
@ -1161,10 +1159,12 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
sockopt_release_sock(sk);
if (!skb) {
if (np->rxopt.bits.rxinfo) {
int mcast_oif = READ_ONCE(np->mcast_oif);
struct in6_pktinfo src_info;
src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
src_info.ipi6_ifindex = mcast_oif ? :
np->sticky_pktinfo.ipi6_ifindex;
src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
}
if (np->rxopt.bits.rxhlim) {
@ -1178,11 +1178,13 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
}
if (np->rxopt.bits.rxoinfo) {
int mcast_oif = READ_ONCE(np->mcast_oif);
struct in6_pktinfo src_info;
src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
src_info.ipi6_ifindex = mcast_oif ? :
np->sticky_pktinfo.ipi6_ifindex;
src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
np->sticky_pktinfo.ipi6_addr;
src_info.ipi6_addr = mcast_oif ? sk->sk_v6_daddr :
np->sticky_pktinfo.ipi6_addr;
put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
}
if (np->rxopt.bits.rxohlim) {
@ -1359,7 +1361,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
break;
case IPV6_MULTICAST_IF:
val = np->mcast_oif;
val = READ_ONCE(np->mcast_oif);
break;
case IPV6_MULTICAST_ALL:

4
net/ipv6/ping.c
View File

@ -107,7 +107,7 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
oif = np->sticky_pktinfo.ipi6_ifindex;
if (!oif && ipv6_addr_is_multicast(daddr))
oif = np->mcast_oif;
oif = READ_ONCE(np->mcast_oif);
else if (!oif)
oif = np->ucast_oif;
@ -157,7 +157,7 @@ static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
rt = (struct rt6_info *) dst;
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
fl6.flowi6_oif = np->mcast_oif;
fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
else if (!fl6.flowi6_oif)
fl6.flowi6_oif = np->ucast_oif;

2
net/ipv6/raw.c
View File

@ -876,7 +876,7 @@ static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
final_p = fl6_update_dst(&fl6, opt, &final);
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
fl6.flowi6_oif = np->mcast_oif;
fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
else if (!fl6.flowi6_oif)
fl6.flowi6_oif = np->ucast_oif;
security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));

2
net/ipv6/tcp_ipv6.c
View File

@ -1702,7 +1702,7 @@ ipv6_pktoptions:
if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
!((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
np->mcast_oif = tcp_v6_iif(opt_skb);
WRITE_ONCE(np->mcast_oif, tcp_v6_iif(opt_skb));
if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
WRITE_ONCE(np->mcast_hops,
ipv6_hdr(opt_skb)->hop_limit);

2
net/ipv6/udp.c
View File

@ -1541,7 +1541,7 @@ do_udp_sendmsg:
connected = false;
if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) {
fl6->flowi6_oif = np->mcast_oif;
fl6->flowi6_oif = READ_ONCE(np->mcast_oif);
connected = false;
} else if (!fl6->flowi6_oif)
fl6->flowi6_oif = np->ucast_oif;

2
net/l2tp/l2tp_ip6.c
View File

@ -599,7 +599,7 @@ static int l2tp_ip6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
final_p = fl6_update_dst(&fl6, opt, &final);
if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
fl6.flowi6_oif = np->mcast_oif;
fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
else if (!fl6.flowi6_oif)
fl6.flowi6_oif = np->ucast_oif;

2
net/netfilter/ipvs/ip_vs_sync.c
View File

@ -1365,7 +1365,7 @@ static int set_mcast_if(struct sock *sk, struct net_device *dev)
struct ipv6_pinfo *np = inet6_sk(sk);
/* IPV6_MULTICAST_IF */
np->mcast_oif = dev->ifindex;
WRITE_ONCE(np->mcast_oif, dev->ifindex);
}
#endif
release_sock(sk);

2
net/rds/tcp_listen.c
View File

@ -165,7 +165,7 @@ int rds_tcp_accept_one(struct socket *sock)
struct ipv6_pinfo *inet6;
inet6 = inet6_sk(new_sock->sk);
dev_if = inet6->mcast_oif;
dev_if = READ_ONCE(inet6->mcast_oif);
} else {
dev_if = new_sock->sk->sk_bound_dev_if;
}