From 3ce5efad47b62c57a4f5c54248347085a750ce0e Mon Sep 17 00:00:00 2001 From: Mathias Krause Date: Sun, 7 Apr 2013 01:51:57 +0000 Subject: [PATCH] netrom: fix info leak via msg_name in nr_recvmsg() 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). Cc: Ralf Baechle Signed-off-by: Mathias Krause Signed-off-by: David S. Miller --- net/netrom/af_netrom.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c index d1fa1d9..7fcb307 100644 --- a/net/netrom/af_netrom.c +++ b/net/netrom/af_netrom.c @@ -1173,6 +1173,7 @@ static int nr_recvmsg(struct kiocb *iocb, struct socket *sock, } 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); -- 2.7.4