From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mathias Krause , Ralf Baechle , "David S. Miller" Subject: [ 25/30] netrom: fix info leak via msg_name in nr_recvmsg() Date: Mon, 29 Apr 2013 12:02:49 -0700 Message-Id: <20130429184358.080688530@linuxfoundation.org> In-Reply-To: <20130429184355.299556377@linuxfoundation.org> References: <20130429184355.299556377@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Krause [ Upstream commits 3ce5efad47b62c57a4f5c54248347085a750ce0e and c802d759623acbd6e1ee9fbdabae89159a513913 ] In case msg_name is set the sockaddr info gets filled out, as requested, but the code fails to initialize the padding bytes of struct sockaddr_ax25 inserted by the compiler for alignment. Also the sax25_ndigis member does not get assigned, leaking four more bytes. Both issues lead to the fact that the code will leak uninitialized kernel stack bytes in net/socket.c. Fix both issues by initializing the memory with memset(0). Signed-off-by: Mathias Krause Cc: Ralf Baechle Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/netrom/af_netrom.c | 1 + 1 file changed, 1 insertion(+) --- a/net/netrom/af_netrom.c +++ b/net/netrom/af_netrom.c @@ -1178,6 +1178,7 @@ static int nr_recvmsg(struct kiocb *iocb } 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);