rose: fix info leak via msg_name in rose_recvmsg()

commit 4a184233f21645cf0b719366210ed445d1024d72 upstream.

The code in rose_recvmsg() does not initialize all of the members of
struct sockaddr_rose/full_sockaddr_rose when filling the sockaddr info.
Nor does it initialize the padding bytes of the structure inserted by
the compiler for alignment. This will lead to leaking uninitialized
kernel stack bytes in net/socket.c.

Fix the issue by initializing the memory used for sockaddr info with
memset(0).

Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index 547e5cd6d375e5fb7c73d5c2fc8ea3cd790b21ac..11072546d7e933763c14a9c76334d66d848226ae 100644 (file)
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -1277,6 +1277,7 @@ 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;