Merge branch 'infoleaks'

Mathias Krause says:

====================
a few more info leak fixes in the recvmsg path. The error pattern here
is the protocol specific recvmsg function is missing the msg_namelen
assignment -- either completely or in early exit paths that do not
result in errors in __sys_recvmsg()/sys_recvfrom() and, in turn, make
them call move_addr_to_user(), leaking the then still uninitialized
sockaddr_storage stack variable to userland.

My audit was initiated by a rather coarse fix of the leak that can be
found in the grsecurity patch, putting a penalty on protocols complying
to the rules of recvmsg. So credits for finding the leak in the recvmsg
path in __sys_recvmsg() should go to Brad!

The buggy protocols/subsystems are rather obscure anyway. As a missing
assignment of msg_namelen coupled with a missing filling of msg_name
would only result in garbage -- the leak -- in case userland would care
about that information, i.e. would provide a msg_name pointer. But
obviously current userland does not.

While auditing the code for the above pattern I found a few more
'uninitialized members' kind of leaks related to the msg_name filling.
Those are fixed in this series, too.

I have to admit, I failed to test all of the patches due to missing
hardware, e.g. iucv depends on S390 -- hardware I've no access to :/
====================

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

16 files changed, 32 insertions, 3 deletions

diff --git a/net/atm/common.c b/net/atm/common.c
index 7b491006eaf4..737bef59ce89 100644
--- a/net/atm/common.c
+++ b/net/atm/common.c
@@ -531,6 +531,8 @@ int vcc_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
         struct sk_buff *skb;
         int copied, error = -EINVAL;
 
+        msg->msg_namelen = 0;
+
         if (sock->state != SS_CONNECTED)
                 return -ENOTCONN;
 
diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index 7b11f8bc5071..e277e38f736b 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -1642,6 +1642,7 @@ static int ax25_recvmsg(struct kiocb *iocb, struct socket *sock,
                 ax25_address src;
                 const unsigned char *mac = skb_mac_header(skb);
 
+                memset(sax, 0, sizeof(struct full_sockaddr_ax25));
                 ax25_addr_parse(mac + 1, skb->data - mac - 1, &src, NULL,
                                 &digi, NULL, NULL);
                 sax->sax25_family = AF_AX25;
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index d3ee69b35a78..0d1b08cc76e1 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -230,6 +230,8 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
         if (flags & (MSG_OOB))
                 return -EOPNOTSUPP;
 
+        msg->msg_namelen = 0;
+
         skb = skb_recv_datagram(sk, flags, noblock, &err);
         if (!skb) {
                 if (sk->sk_shutdown & RCV_SHUTDOWN)
@@ -237,8 +239,6 @@ int bt_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
                 return err;
         }
 
-        msg->msg_namelen = 0;
-
         copied = skb->len;
         if (len < copied) {
                 msg->msg_flags |= MSG_TRUNC;
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index c23bae86263b..7c9224bcce17 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -608,6 +608,7 @@ static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 
         if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
                 rfcomm_dlc_accept(d);
+                msg->msg_namelen = 0;
                 return 0;
         }
 
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index fad0302bdb32..fb6192c9812e 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -665,6 +665,7 @@ static int sco_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
             test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
                 hci_conn_accept(pi->conn->hcon, 0);
                 sk->sk_state = BT_CONFIG;
+                msg->msg_namelen = 0;
 
                 release_sock(sk);
                 return 0;
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index 095259f83902..ff2ff3ce6965 100644
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -286,6 +286,8 @@ static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
         if (m->msg_flags&MSG_OOB)
                 goto read_error;
 
+        m->msg_namelen = 0;
+
         skb = skb_recv_datagram(sk, flags, 0 , &ret);
         if (!skb)
                 goto read_error;
diff --git a/net/irda/af_irda.c b/net/irda/af_irda.c
index d28e7f014cc6..e493b3397ae3 100644
--- a/net/irda/af_irda.c
+++ b/net/irda/af_irda.c
@@ -1386,6 +1386,8 @@ static int irda_recvmsg_dgram(struct kiocb *iocb, struct socket *sock,
 
         IRDA_DEBUG(4, "%s()\n", __func__);
 
+        msg->msg_namelen = 0;
+
         skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
                                 flags & MSG_DONTWAIT, &err);
         if (!skb)
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index a7d11ffe4284..bf6935820001 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1328,6 +1328,8 @@ static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
         struct sk_buff *skb, *rskb, *cskb;
         int err = 0;
 
+        msg->msg_namelen = 0;
+
         if ((sk->sk_state == IUCV_DISCONN) &&
             skb_queue_empty(&iucv->backlog_skb_q) &&
             skb_queue_empty(&sk->sk_receive_queue) &&
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index c74f5a91ff6a..b8a6039314e8 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -690,6 +690,7 @@ static int l2tp_ip6_recvmsg(struct kiocb *iocb, struct sock *sk,
                 lsa->l2tp_addr = ipv6_hdr(skb)->saddr;
                 lsa->l2tp_flowinfo = 0;
                 lsa->l2tp_scope_id = 0;
+                lsa->l2tp_conn_id = 0;
                 if (ipv6_addr_type(&lsa->l2tp_addr) & IPV6_ADDR_LINKLOCAL)
                         lsa->l2tp_scope_id = IP6CB(skb)->iif;
         }
diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
index 88709882c464..48aaa89253e0 100644
--- a/net/llc/af_llc.c
+++ b/net/llc/af_llc.c
@@ -720,6 +720,8 @@ static int llc_ui_recvmsg(struct kiocb *iocb, struct socket *sock,
         int target;     /* Read at least this many bytes */
         long timeo;
 
+        msg->msg_namelen = 0;
+
         lock_sock(sk);
         copied = -ENOTCONN;
         if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
index d1fa1d9ffd2e..7fcb307dea47 100644
--- a/net/netrom/af_netrom.c
+++ b/net/netrom/af_netrom.c
@@ -1173,6 +1173,7 @@ static int nr_recvmsg(struct kiocb *iocb, struct socket *sock,
         }
 
         if (sax != NULL) {
+                memset(sax, 0, sizeof(sax));
                 sax->sax25_family = AF_NETROM;
                 skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
                               AX25_ADDR_LEN);
diff --git a/net/nfc/llcp/sock.c b/net/nfc/llcp/sock.c
index 8f025746f337..6c94447ec414 100644
--- a/net/nfc/llcp/sock.c
+++ b/net/nfc/llcp/sock.c
@@ -646,6 +646,8 @@ static int llcp_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 
         pr_debug("%p %zu\n", sk, len);
 
+        msg->msg_namelen = 0;
+
         lock_sock(sk);
 
         if (sk->sk_state == LLCP_CLOSED &&
@@ -691,6 +693,7 @@ static int llcp_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
 
                 pr_debug("Datagram socket %d %d\n", ui_cb->dsap, ui_cb->ssap);
 
+                memset(sockaddr, 0, sizeof(*sockaddr));
                 sockaddr->sa_family = AF_NFC;
                 sockaddr->nfc_protocol = NFC_PROTO_NFC_DEP;
                 sockaddr->dsap = ui_cb->dsap;
diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index cf68e6e4054a..9c8347451597 100644
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -1253,6 +1253,7 @@ static int rose_recvmsg(struct kiocb *iocb, struct socket *sock,
         skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 
         if (srose != NULL) {
+                memset(srose, 0, msg->msg_namelen);
                 srose->srose_family = AF_ROSE;
                 srose->srose_addr   = rose->dest_addr;
                 srose->srose_call   = rose->dest_call;
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index a9622b6cd916..515ce38e4f4c 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -790,6 +790,7 @@ static void set_orig_addr(struct msghdr *m, struct tipc_msg *msg)
         if (addr) {
                 addr->family = AF_TIPC;
                 addr->addrtype = TIPC_ADDR_ID;
+                memset(&addr->addr, 0, sizeof(addr->addr));
                 addr->addr.id.ref = msg_origport(msg);
                 addr->addr.id.node = msg_orignode(msg);
                 addr->addr.name.domain = 0;     /* could leave uninitialized */
@@ -904,6 +905,9 @@ static int recv_msg(struct kiocb *iocb, struct socket *sock,
                 goto exit;
         }
 
+        /* will be updated in set_orig_addr() if needed */
+        m->msg_namelen = 0;
+
         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
 restart:
 
@@ -1013,6 +1017,9 @@ static int recv_stream(struct kiocb *iocb, struct socket *sock,
                 goto exit;
         }
 
+        /* will be updated in set_orig_addr() if needed */
+        m->msg_namelen = 0;
+
         target = sock_rcvlowat(sk, flags & MSG_WAITALL, buf_len);
         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
 
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index d8079daf1bde..7f93e2a42d7a 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -1670,6 +1670,8 @@ vsock_stream_recvmsg(struct kiocb *kiocb,
         vsk = vsock_sk(sk);
         err = 0;
 
+        msg->msg_namelen = 0;
+
         lock_sock(sk);
 
         if (sk->sk_state != SS_CONNECTED) {
diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c
index 1f6508e249ae..5e04d3d96285 100644
--- a/net/vmw_vsock/vmci_transport.c
+++ b/net/vmw_vsock/vmci_transport.c
@@ -1736,6 +1736,8 @@ static int vmci_transport_dgram_dequeue(struct kiocb *kiocb,
         if (flags & MSG_OOB || flags & MSG_ERRQUEUE)
                 return -EOPNOTSUPP;
 
+        msg->msg_namelen = 0;
+
         /* Retrieve the head sk_buff from the socket's receive queue. */
         err = 0;
         skb = skb_recv_datagram(&vsk->sk, flags, noblock, &err);
@@ -1768,7 +1770,6 @@ static int vmci_transport_dgram_dequeue(struct kiocb *kiocb,
         if (err)
                 goto out;
 
-        msg->msg_namelen = 0;
         if (msg->msg_name) {
                 struct sockaddr_vm *vm_addr;