From 680d04e0ba7e926233e3b9cee59125ce181f66ba Mon Sep 17 00:00:00 2001 From: Mathias Krause Date: Sun, 7 Apr 2013 01:52:01 +0000 Subject: VSOCK: vmci - fix possible info leak in vmci_transport_dgram_dequeue() In case we received no data on the call to skb_recv_datagram(), i.e. skb->data is NULL, vmci_transport_dgram_dequeue() will return with 0 without updating msg_namelen leading to net/socket.c leaking the local, uninitialized sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. Fix this by moving the already existing msg_namelen assignment a few lines above. Cc: Andy King Cc: Dmitry Torokhov Cc: George Zhang Signed-off-by: Mathias Krause Signed-off-by: David S. Miller --- net/vmw_vsock/vmci_transport.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/vmw_vsock') diff --git a/net/vmw_vsock/vmci_transport.c b/net/vmw_vsock/vmci_transport.c index 1f6508e..5e04d3d 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; -- cgit v1.1 From d5e0d0f607a7a029c6563a0470d88255c89a8d11 Mon Sep 17 00:00:00 2001 From: Mathias Krause Date: Sun, 7 Apr 2013 01:52:02 +0000 Subject: VSOCK: Fix missing msg_namelen update in vsock_stream_recvmsg() The code misses to update the msg_namelen member to 0 and therefore makes net/socket.c leak the local, uninitialized sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. Cc: Andy King Cc: Dmitry Torokhov Cc: George Zhang Signed-off-by: Mathias Krause Signed-off-by: David S. Miller --- net/vmw_vsock/af_vsock.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'net/vmw_vsock') diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index d8079da..7f93e2a 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) { -- cgit v1.1