diff options
Diffstat (limited to 'net/ipv4/ip_sockglue.c')
| -rw-r--r-- | net/ipv4/ip_sockglue.c | 47 |
1 files changed, 32 insertions, 15 deletions
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 64b70ad162e3..ab0c9efd1efa 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -131,7 +131,7 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb) static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb) { struct sockaddr_in sin; - struct iphdr *iph = ip_hdr(skb); + const struct iphdr *iph = ip_hdr(skb); __be16 *ports = (__be16 *)skb_transport_header(skb); if (skb_transport_offset(skb) + 4 > skb->len) @@ -238,7 +238,7 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc) but receiver should be enough clever f.e. to forward mtrace requests, sent to multicast group to reach destination designated router. */ -struct ip_ra_chain *ip_ra_chain; +struct ip_ra_chain __rcu *ip_ra_chain; static DEFINE_SPINLOCK(ip_ra_lock); @@ -253,7 +253,8 @@ static void ip_ra_destroy_rcu(struct rcu_head *head) int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *)) { - struct ip_ra_chain *ra, *new_ra, **rap; + struct ip_ra_chain *ra, *new_ra; + struct ip_ra_chain __rcu **rap; if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW) return -EINVAL; @@ -261,7 +262,10 @@ int ip_ra_control(struct sock *sk, unsigned char on, new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; spin_lock_bh(&ip_ra_lock); - for (rap = &ip_ra_chain; (ra = *rap) != NULL; rap = &ra->next) { + for (rap = &ip_ra_chain; + (ra = rcu_dereference_protected(*rap, + lockdep_is_held(&ip_ra_lock))) != NULL; + rap = &ra->next) { if (ra->sk == sk) { if (on) { spin_unlock_bh(&ip_ra_lock); @@ -447,6 +451,11 @@ out: } +static void opt_kfree_rcu(struct rcu_head *head) +{ + kfree(container_of(head, struct ip_options_rcu, rcu)); +} + /* * Socket option code for IP. This is the end of the line after any * TCP,UDP etc options on an IP socket. @@ -493,13 +502,16 @@ static int do_ip_setsockopt(struct sock *sk, int level, switch (optname) { case IP_OPTIONS: { - struct ip_options *opt = NULL; + struct ip_options_rcu *old, *opt = NULL; + if (optlen > 40) goto e_inval; err = ip_options_get_from_user(sock_net(sk), &opt, optval, optlen); if (err) break; + old = rcu_dereference_protected(inet->inet_opt, + sock_owned_by_user(sk)); if (inet->is_icsk) { struct inet_connection_sock *icsk = inet_csk(sk); #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) @@ -508,17 +520,18 @@ static int do_ip_setsockopt(struct sock *sk, int level, (TCPF_LISTEN | TCPF_CLOSE)) && inet->inet_daddr != LOOPBACK4_IPV6)) { #endif - if (inet->opt) - icsk->icsk_ext_hdr_len -= inet->opt->optlen; + if (old) + icsk->icsk_ext_hdr_len -= old->opt.optlen; if (opt) - icsk->icsk_ext_hdr_len += opt->optlen; + icsk->icsk_ext_hdr_len += opt->opt.optlen; icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie); #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) } #endif } - opt = xchg(&inet->opt, opt); - kfree(opt); + rcu_assign_pointer(inet->inet_opt, opt); + if (old) + call_rcu(&old->rcu, opt_kfree_rcu); break; } case IP_PKTINFO: @@ -1077,12 +1090,16 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, case IP_OPTIONS: { unsigned char optbuf[sizeof(struct ip_options)+40]; - struct ip_options * opt = (struct ip_options *)optbuf; + struct ip_options *opt = (struct ip_options *)optbuf; + struct ip_options_rcu *inet_opt; + + inet_opt = rcu_dereference_protected(inet->inet_opt, + sock_owned_by_user(sk)); opt->optlen = 0; - if (inet->opt) - memcpy(optbuf, inet->opt, - sizeof(struct ip_options)+ - inet->opt->optlen); + if (inet_opt) + memcpy(optbuf, &inet_opt->opt, + sizeof(struct ip_options) + + inet_opt->opt.optlen); release_sock(sk); if (opt->optlen == 0) |