diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-09-12 16:01:59 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-09-15 10:33:46 +0100 |
| commit | b0adfba7ee770fef20b1b6d86706c28f7fccfb07 (patch) | |
| tree | 4a7a9fe910c850fcc4492d034cf57d0db89c4ae2 /net/ipv6 | |
| parent | f2fa1c812c91e99d0317d1fc7d845e1e05f39716 (diff) | |
ipv6: lockless IPV6_UNICAST_HOPS implementation
Some np->hop_limit accesses are racy, when socket lock is not held.
Add missing annotations and switch to full lockless implementation.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/ip6_output.c | 2 | ||||
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 20 | ||||
| -rw-r--r-- | net/ipv6/mcast.c | 2 | ||||
| -rw-r--r-- | net/ipv6/ndisc.c | 2 |
4 files changed, 14 insertions, 12 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 54fc4c711f2c..1e16d56d8c38 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -309,7 +309,7 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, * Fill in the IPv6 header */ if (np) - hlimit = np->hop_limit; + hlimit = READ_ONCE(np->hop_limit); if (hlimit < 0) hlimit = ip6_dst_hoplimit(dst); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 0e2a0847b387..f27993a1470d 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -415,6 +415,16 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname, if (ip6_mroute_opt(optname)) return ip6_mroute_setsockopt(sk, optname, optval, optlen); + /* Handle options that can be set without locking the socket. */ + switch (optname) { + case IPV6_UNICAST_HOPS: + if (optlen < sizeof(int)) + return -EINVAL; + if (val > 255 || val < -1) + return -EINVAL; + WRITE_ONCE(np->hop_limit, val); + return 0; + } if (needs_rtnl) rtnl_lock(); sockopt_lock_sock(sk); @@ -733,14 +743,6 @@ done: } break; } - case IPV6_UNICAST_HOPS: - if (optlen < sizeof(int)) - goto e_inval; - if (val > 255 || val < -1) - goto e_inval; - np->hop_limit = val; - retv = 0; - break; case IPV6_MULTICAST_HOPS: if (sk->sk_type == SOCK_STREAM) @@ -1347,7 +1349,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname, struct dst_entry *dst; if (optname == IPV6_UNICAST_HOPS) - val = np->hop_limit; + val = READ_ONCE(np->hop_limit); else val = np->mcast_hops; diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index 421264a69e97..4a7967623909 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -1716,7 +1716,7 @@ static void ip6_mc_hdr(const struct sock *sk, struct sk_buff *skb, hdr->payload_len = htons(len); hdr->nexthdr = proto; - hdr->hop_limit = inet6_sk(sk)->hop_limit; + hdr->hop_limit = READ_ONCE(inet6_sk(sk)->hop_limit); hdr->saddr = *saddr; hdr->daddr = *daddr; diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 553c8664e0a7..b554fd40bdc3 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -500,7 +500,7 @@ void ndisc_send_skb(struct sk_buff *skb, const struct in6_addr *daddr, csum_partial(icmp6h, skb->len, 0)); - ip6_nd_hdr(skb, saddr, daddr, inet6_sk(sk)->hop_limit, skb->len); + ip6_nd_hdr(skb, saddr, daddr, READ_ONCE(inet6_sk(sk)->hop_limit), skb->len); rcu_read_lock(); idev = __in6_dev_get(dst->dev); |