diff mbox series

[RFC,1] Validate required parameters in inet6_validate_link_af

Message ID 20190513150513.26872-2-maximmi@mellanox.com
State RFC
Delegated to: David Miller
Headers show
Series [RFC,1] Validate required parameters in inet6_validate_link_af | expand

Commit Message

Maxim Mikityanskiy May 13, 2019, 3:05 p.m. UTC 
inet6_set_link_af requires that at least one of IFLA_INET6_TOKEN or
IFLA_INET6_ADDR_GET_MODE is passed. If none of them is passed, it
returns -EINVAL, which may cause do_setlink() to fail in the middle of
processing other commands and give the following warning message:

  A link change request failed with some changes committed already.
  Interface eth0 may have been left with an inconsistent configuration,
  please check.

Check the presence of at least one of them in inet6_validate_link_af to
detect invalid parameters at an early stage, before do_setlink does
anything.

Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
---
 net/ipv6/addrconf.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index f96d1de79509..ef38d381ccbd 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5665,12 +5665,20 @@  static int inet6_validate_link_af(const struct net_device *dev,
 				  const struct nlattr *nla)
 {
 	struct nlattr *tb[IFLA_INET6_MAX + 1];
+	int err;
 
 	if (dev && !__in6_dev_get(dev))
 		return -EAFNOSUPPORT;
 
-	return nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
-					   inet6_af_policy, NULL);
+	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
+					  inet6_af_policy, NULL);
+	if (err)
+		return err;
+
+	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
+		return -EINVAL;
+
+	return 0;
 }
 
 static int check_addr_gen_mode(int mode)