ipv6: lockless IPV6_RECVERR implemetation

np->recverr is moved to inet->inet_flags to fix data-races.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 57d563f1d4b1707264f0d79406c4c139cc0fa525..53f4f1b97a787ac01fc274a8057494a28fa270fd 100644 (file)
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -243,8 +243,7 @@ struct ipv6_pinfo {
        } rxopt;
 
        /* sockopt flags */
-       __u16                   recverr:1,
-                               sndflow:1,
+       __u16                   sndflow:1,
                                repflow:1,
                                pmtudisc:3,
                                padding:1,      /* 1 bit hole */

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index ac75324e9e1eafe68cee7b0581e472cbb4f49aa3..3b79bc759ff478f96d729f2669c6963bbe768ba1 100644 (file)
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -274,6 +274,7 @@ enum {
        INET_FLAGS_AUTOFLOWLABEL_SET = 23,
        INET_FLAGS_AUTOFLOWLABEL = 24,
        INET_FLAGS_DONTFRAG     = 25,
+       INET_FLAGS_RECVERR6     = 26,
 };
 
 /* cmsg flags for inet */

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 5a1f2993680dacc97013a000d487ff781b664c6b..bd115980809f386a7d38a5471d8d636f25ce1eba 100644 (file)
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -1303,9 +1303,7 @@ static inline int ip6_sock_set_v6only(struct sock *sk)
 
 static inline void ip6_sock_set_recverr(struct sock *sk)
 {
-       lock_sock(sk);
-       inet6_sk(sk)->recverr = true;
-       release_sock(sk);
+       inet6_set_bit(RECVERR6, sk);
 }
 
 static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val)

diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 83617a16b98e70aa577c08a394df63e006e53e9e..e6c3d84c2b9ec2df9b89ab0879991b3b312d0b6f 100644 (file)
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -185,7 +185,7 @@ static int dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
                goto out;
        }
 
-       if (!sock_owned_by_user(sk) && np->recverr) {
+       if (!sock_owned_by_user(sk) && inet6_test_bit(RECVERR6, sk)) {
                sk->sk_err = err;
                sk_error_report(sk);
        } else {

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 75e0aee35eb787a6c9f70394294b30490c980a64..bc01ad5fc01ab97f71f7704a671eaf644ec040be 100644 (file)
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -581,7 +581,7 @@ void ping_err(struct sk_buff *skb, int offset, u32 info)
         *      4.1.3.3.
         */
        if ((family == AF_INET && !inet_test_bit(RECVERR, sk)) ||
-           (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
+           (family == AF_INET6 && !inet6_test_bit(RECVERR6, sk))) {
                if (!harderr || sk->sk_state != TCP_ESTABLISHED)
                        goto out;
        } else {

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index e81892814935fb3934fbf0e6f9defc702ec29152..74673a5eff319f23871e64584a33f5299fa7b521 100644 (file)
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -305,11 +305,10 @@ static void ipv6_icmp_error_rfc4884(const struct sk_buff *skb,
 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
                     __be16 port, u32 info, u8 *payload)
 {
-       struct ipv6_pinfo *np  = inet6_sk(sk);
        struct icmp6hdr *icmph = icmp6_hdr(skb);
        struct sock_exterr_skb *serr;
 
-       if (!np->recverr)
+       if (!inet6_test_bit(RECVERR6, sk))
                return;
 
        skb = skb_clone(skb, GFP_ATOMIC);
@@ -344,12 +343,11 @@ EXPORT_SYMBOL_GPL(ipv6_icmp_error);
 
 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
 {
-       const struct ipv6_pinfo *np = inet6_sk(sk);
        struct sock_exterr_skb *serr;
        struct ipv6hdr *iph;
        struct sk_buff *skb;
 
-       if (!np->recverr)
+       if (!inet6_test_bit(RECVERR6, sk))
                return;
 
        skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 33dd4dd872e6bca2ee18a634283640007adcc692..ec10b45c49c15f9655466a529046f741f8b9fc69 100644 (file)
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -481,6 +481,13 @@ int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
        case IPV6_DONTFRAG:
                inet6_assign_bit(DONTFRAG, sk, valbool);
                return 0;
+       case IPV6_RECVERR:
+               if (optlen < sizeof(int))
+                       return -EINVAL;
+               inet6_assign_bit(RECVERR6, sk, valbool);
+               if (!val)
+                       skb_errqueue_purge(&sk->sk_error_queue);
+               return 0;
        }
        if (needs_rtnl)
                rtnl_lock();
@@ -943,14 +950,6 @@ done:
                np->pmtudisc = val;
                retv = 0;
                break;
-       case IPV6_RECVERR:
-               if (optlen < sizeof(int))
-                       goto e_inval;
-               np->recverr = valbool;
-               if (!val)
-                       skb_errqueue_purge(&sk->sk_error_queue);
-               retv = 0;
-               break;
        case IPV6_FLOWINFO_SEND:
                if (optlen < sizeof(int))
                        goto e_inval;
@@ -1380,7 +1379,7 @@ int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
                break;
 
        case IPV6_RECVERR:
-               val = np->recverr;
+               val = inet6_test_bit(RECVERR6, sk);
                break;
 
        case IPV6_FLOWINFO_SEND:

diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index cc9673c1809fb238f6d9ab6915116cf0dd6eb593..71f6bdccfa1f39290e1b573ff8c647d91fd007a4 100644 (file)
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -291,6 +291,7 @@ static void rawv6_err(struct sock *sk, struct sk_buff *skb,
               struct inet6_skb_parm *opt,
               u8 type, u8 code, int offset, __be32 info)
 {
+       bool recverr = inet6_test_bit(RECVERR6, sk);
        struct ipv6_pinfo *np = inet6_sk(sk);
        int err;
        int harderr;
@@ -300,7 +301,7 @@ static void rawv6_err(struct sock *sk, struct sk_buff *skb,
           2. Socket is connected (otherwise the error indication
              is useless without recverr and error is hard.
         */
-       if (!np->recverr && sk->sk_state != TCP_ESTABLISHED)
+       if (!recverr && sk->sk_state != TCP_ESTABLISHED)
                return;
 
        harderr = icmpv6_err_convert(type, code, &err);
@@ -312,14 +313,14 @@ static void rawv6_err(struct sock *sk, struct sk_buff *skb,
                ip6_sk_redirect(skb, sk);
                return;
        }
-       if (np->recverr) {
+       if (recverr) {
                u8 *payload = skb->data;
                if (!inet_test_bit(HDRINCL, sk))
                        payload += offset;
                ipv6_icmp_error(sk, skb, err, 0, ntohl(info), payload);
        }
 
-       if (np->recverr || harderr) {
+       if (recverr || harderr) {
                sk->sk_err = err;
                sk_error_report(sk);
        }
@@ -587,7 +588,6 @@ static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
                        struct flowi6 *fl6, struct dst_entry **dstp,
                        unsigned int flags, const struct sockcm_cookie *sockc)
 {
-       struct ipv6_pinfo *np = inet6_sk(sk);
        struct net *net = sock_net(sk);
        struct ipv6hdr *iph;
        struct sk_buff *skb;
@@ -668,7 +668,7 @@ out:
 error:
        IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
 error_check:
-       if (err == -ENOBUFS && !np->recverr)
+       if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk))
                err = 0;
        return err;
 }

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 54db5fab318bc68cf9efbe6f26dacba614fa8562..b5954b136b57306429690594238f7a01b0cf15de 100644 (file)
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -508,7 +508,7 @@ static int tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
                        tcp_ld_RTO_revert(sk, seq);
        }
 
-       if (!sock_owned_by_user(sk) && np->recverr) {
+       if (!sock_owned_by_user(sk) && inet6_test_bit(RECVERR6, sk)) {
                WRITE_ONCE(sk->sk_err, err);
                sk_error_report(sk);
        } else {

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index e4301500741a0ea79228d90860ee7f942b73d543..90e873689b885c13dd4eba4e1b6edd3df6b1daf2 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -619,7 +619,7 @@ int __udp6_lib_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
                goto out;
        }
 
-       if (!np->recverr) {
+       if (!inet6_test_bit(RECVERR6, sk)) {
                if (!harderr || sk->sk_state != TCP_ESTABLISHED)
                        goto out;
        } else {
@@ -1283,7 +1283,7 @@ csum_partial:
 send:
        err = ip6_send_skb(skb);
        if (err) {
-               if (err == -ENOBUFS && !inet6_sk(sk)->recverr) {
+               if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk)) {
                        UDP6_INC_STATS(sock_net(sk),
                                       UDP_MIB_SNDBUFERRORS, is_udplite);
                        err = 0;
@@ -1608,7 +1608,7 @@ do_append_data:
                up->pending = 0;
 
        if (err > 0)
-               err = np->recverr ? net_xmit_errno(err) : 0;
+               err = inet6_test_bit(RECVERR6, sk) ? net_xmit_errno(err) : 0;
        release_sock(sk);
 
 out:

diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 43f2731bf590e5757b7ad2d3a92a12e4098e0d47..42b5b853ea01c767e1fe878772eeabe5c05adb6d 100644 (file)
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -128,7 +128,6 @@ static void sctp_v6_err_handle(struct sctp_transport *t, struct sk_buff *skb,
 {
        struct sctp_association *asoc = t->asoc;
        struct sock *sk = asoc->base.sk;
-       struct ipv6_pinfo *np;
        int err = 0;
 
        switch (type) {
@@ -149,9 +148,8 @@ static void sctp_v6_err_handle(struct sctp_transport *t, struct sk_buff *skb,
                break;
        }
 
-       np = inet6_sk(sk);
        icmpv6_err_convert(type, code, &err);
-       if (!sock_owned_by_user(sk) && np->recverr) {
+       if (!sock_owned_by_user(sk) && inet6_test_bit(RECVERR6, sk)) {
                sk->sk_err = err;
                sk_error_report(sk);
        } else {