nl80211: require and validate vendor command policy

Require that each vendor command give a policy of its sub-attributes
in NL80211_ATTR_VENDOR_DATA, and then (stricly) check the contents,
including the NLA_F_NESTED flag that we couldn't check on the outer
layer because there we don't know yet.

It is possible to use VENDOR_CMD_RAW_DATA for raw data, but then no
nested data can be given (NLA_F_NESTED flag must be clear) and the
data is just passed as is to the command.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 395b4406f4b08..28ece67f53127 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -1755,6 +1755,15 @@ static inline int __nla_validate_nested(const struct nlattr *start, int maxtype,
 }
 
 static inline int
+nl80211_validate_nested(const struct nlattr *start, int maxtype,
+			const struct nla_policy *policy,
+			struct netlink_ext_ack *extack)
+{
+	return __nla_validate_nested(start, maxtype, policy,
+				     NL_VALIDATE_STRICT, extack);
+}
+
+static inline int
 nla_validate_nested_deprecated(const struct nlattr *start, int maxtype,
 			       const struct nla_policy *policy,
 			       struct netlink_ext_ack *extack)