netlink: add NLA_MIN_LEN
Rather than using NLA_UNSPEC for this type of thing, use NLA_MIN_LEN
so we can make NLA_UNSPEC be NLA_REJECT under certain conditions for
future attributes.
While at it, also use NLA_EXACT_LEN for the struct example.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/lib/nlattr.c b/lib/nlattr.c
index d26de61..465c9e8 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -278,10 +278,17 @@
}
}
break;
+
+ case NLA_UNSPEC:
+ case NLA_MIN_LEN:
+ if (attrlen < pt->len)
+ goto out_err;
+ break;
+
default:
if (pt->len)
minlen = pt->len;
- else if (pt->type != NLA_UNSPEC)
+ else
minlen = nla_attr_minlen[pt->type];
if (attrlen < minlen)