[TCP]: Invoke tcp_sendmsg() directly, do not use inet_sendmsg().

As discovered by Evegniy Polyakov, if we try to sendmsg after
a connection reset, we can do incredibly stupid things.

The core issue is that inet_sendmsg() tries to autobind the
socket, but we should never do that for TCP.  Instead we should
just go straight into TCP's sendmsg() code which will do all
of the necessary state and pending socket error checks.

TCP's sendpage already directly vectors to tcp_sendpage(), so this
merely brings sendmsg() in line with that.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index c209361..185c7ec 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -281,7 +281,7 @@ extern int                  tcp_v4_remember_stamp(struct sock *sk);
 
 extern int                     tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);
 
-extern int                     tcp_sendmsg(struct kiocb *iocb, struct sock *sk,
+extern int                     tcp_sendmsg(struct kiocb *iocb, struct socket *sock,
                                            struct msghdr *msg, size_t size);
 extern ssize_t                 tcp_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags);
 

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 06c08e5..e681034 100644 (file)
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -831,7 +831,7 @@ const struct proto_ops inet_stream_ops = {
        .shutdown          = inet_shutdown,
        .setsockopt        = sock_common_setsockopt,
        .getsockopt        = sock_common_getsockopt,
-       .sendmsg           = inet_sendmsg,
+       .sendmsg           = tcp_sendmsg,
        .recvmsg           = sock_common_recvmsg,
        .mmap              = sock_no_mmap,
        .sendpage          = tcp_sendpage,

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index da4c0b6..7e74011 100644 (file)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -658,9 +658,10 @@ static inline int select_size(struct sock *sk)
        return tmp;
 }
 
-int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
+int tcp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
                size_t size)
 {
+       struct sock *sk = sock->sk;
        struct iovec *iov;
        struct tcp_sock *tp = tcp_sk(sk);
        struct sk_buff *skb;

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 3f5f742..9c94627 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2425,7 +2425,6 @@ struct proto tcp_prot = {
        .shutdown               = tcp_shutdown,
        .setsockopt             = tcp_setsockopt,
        .getsockopt             = tcp_getsockopt,
-       .sendmsg                = tcp_sendmsg,
        .recvmsg                = tcp_recvmsg,
        .backlog_rcv            = tcp_v4_do_rcv,
        .hash                   = tcp_v4_hash,

diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index eed0937..b5f9637 100644 (file)
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -484,7 +484,7 @@ const struct proto_ops inet6_stream_ops = {
        .shutdown          = inet_shutdown,             /* ok           */
        .setsockopt        = sock_common_setsockopt,    /* ok           */
        .getsockopt        = sock_common_getsockopt,    /* ok           */
-       .sendmsg           = inet_sendmsg,              /* ok           */
+       .sendmsg           = tcp_sendmsg,               /* ok           */
        .recvmsg           = sock_common_recvmsg,       /* ok           */
        .mmap              = sock_no_mmap,
        .sendpage          = tcp_sendpage,

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index f10f368..cbdb784 100644 (file)
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -2115,7 +2115,6 @@ struct proto tcpv6_prot = {
        .shutdown               = tcp_shutdown,
        .setsockopt             = tcp_setsockopt,
        .getsockopt             = tcp_getsockopt,
-       .sendmsg                = tcp_sendmsg,
        .recvmsg                = tcp_recvmsg,
        .backlog_rcv            = tcp_v6_do_rcv,
        .hash                   = tcp_v6_hash,