rose: fix info leak via msg_name in rose_recvmsg()

[ Upstream commit 4a184233f21645cf0b719366210ed445d1024d72 ]

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).

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/rose/af_rose.c b/net/rose/af_rose.c
index c4719ce604c28040b1cfdc9bff0f3a9ee4d2200d..7f645d115795e87dfd493527ee4814e23250d5d0 100644 (file)
--- a/net/rose/af_rose.c
+++ b/net/rose/af_rose.c
@@ -1257,6 +1257,7 @@ 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;