netdev - [PATCH net-next 11/20] rtnetlink: Update inet6_dump

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu,  4 Oct 2018 14:33:46 -0700
From:   David Ahern <dsahern@...nel.org>
To:     netdev@...r.kernel.org, davem@...emloft.net
Cc:     christian@...uner.io, jbenc@...hat.com, stephen@...workplumber.org,
        David Ahern <dsahern@...il.com>
Subject: [PATCH net-next 11/20] rtnetlink: Update inet6_dump_ifinfo for strict data checking

From: David Ahern <dsahern@...il.com>

Update inet6_dump_ifinfo for strict data checking. If the flag is
set, the dump request is expected to have an ifinfomsg struct as
the header. All elements of the struct are expected to be 0 and no
attributes can be appended.

Signed-off-by: David Ahern <dsahern@...il.com>
---
 net/ipv6/addrconf.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index f749a3ad721a..693199a29426 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5628,6 +5628,31 @@ static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
 	return -EMSGSIZE;
 }
 
+static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
+				   struct netlink_ext_ack *extack)
+{
+	struct ifinfomsg *ifm;
+
+	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
+		NL_SET_ERR_MSG(extack, "Invalid header");
+		return -EINVAL;
+	}
+
+	if (nlh->nlmsg_len > nlmsg_msg_size(sizeof(*ifm))) {
+		NL_SET_ERR_MSG(extack, "Invalid data after header");
+		return -EINVAL;
+	}
+
+	ifm = nlmsg_data(nlh);
+	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
+	    ifm->ifi_change || ifm->ifi_index) {
+		NL_SET_ERR_MSG(extack, "Invalid values in header for dump request");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct net *net = sock_net(skb->sk);
@@ -5637,6 +5662,16 @@ static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 	struct inet6_dev *idev;
 	struct hlist_head *head;
 
+	/* only requests using strict checking can pass data to
+	 * influence the dump
+	 */
+	if (cb->strict_check) {
+		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
+
+		if (err)
+			return err;
+	}
+
 	s_h = cb->args[0];
 	s_idx = cb->args[1];
 
-- 
2.11.0