caif: Fix missing msg_namelen update in caif_seqpkt_recvmsg()

[ Upstream commit 2d6fbfe733f35c6b355c216644e08e149c61b271 ]

The current code does not fill the msg_name member in case it is set.
It also does not set 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.

Fix that by simply setting msg_namelen to 0 as obviously nobody cared
about caif_seqpkt_recvmsg() not filling the msg_name in case it was
set.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
index a986280864523d431e8f30f96af1a346abe2b784..53a8e37d020a3f1cbe28b4de9f5ce006380d8f50 100644 (file)
--- a/net/caif/caif_socket.c
+++ b/net/caif/caif_socket.c
@@ -320,6 +320,8 @@ 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;