[PATCH 1/1] net/rds: Fix info leak in rds6_inc_info_copy()

[Tyler Hicks]

From: Ka-Cheong Poon <ka-cheong.poon at oracle.com>

The rds6_inc_info_copy() function has a couple struct members which
are leaking stack information.  The ->tos field should hold actual
information and the ->flags field needs to be zeroed out.

Fixes: 3eb450367d08 ("rds: add type of service(tos) infrastructure")
Fixes: b7ff8b1036f0 ("rds: Extend RDS API for IPv6 support")
Reported-by: 黄ID蝴蝶 <butterflyhuangxx at gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
Signed-off-by: Ka-Cheong Poon <ka-cheong.poon at oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar at oracle.com>
Signed-off-by: David S. Miller <davem at davemloft.net>

CVE-2019-16714

(backported from commit 7d0a06586b2686ba80c4a2da5f91cb10ffbea736)
[tyhicks: Initialize minfo6.tos to 0 since the rds_incoming struct
 doesn't have a c_tos field due to 5.0 not containing commit
 3eb450367d08 ("rds: add type of service(tos) infrastructure")]
Signed-off-by: Tyler Hicks <tyhicks at canonical.com>
---
 net/rds/recv.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/rds/recv.c b/net/rds/recv.c
index 727639dac8a7..7ca2bc4bbc0d 100644
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2019 Oracle and/or its affiliates. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
@@ -798,6 +798,7 @@ void rds6_inc_info_copy(struct rds_incoming *inc,
 
 	minfo6.seq = be64_to_cpu(inc->i_hdr.h_sequence);
 	minfo6.len = be32_to_cpu(inc->i_hdr.h_len);
+	minfo6.tos = 0;
 
 	if (flip) {
 		minfo6.laddr = *daddr;
@@ -811,6 +812,8 @@ void rds6_inc_info_copy(struct rds_incoming *inc,
 		minfo6.fport = inc->i_hdr.h_dport;
 	}
 
+	minfo6.flags = 0;
+
 	rds_info_copy(iter, &minfo6, sizeof(minfo6));
 }
 #endif
-- 
2.17.1