[PATCH] attr: Allow attribute type 0

[Thomas Graf]

{netlink,packet,unix}_diag use attribute type 0 for valid
attributes. The value was reserved and usage was prohibited
by the protocol but we can't undo the breakge.

Make libnl accept attribute type 0 to allow parsing these
attributes.

Reported-by: Nicolas Dichtel <nicolas.dichtel at 6wind.com>
Signed-off-by: Thomas Graf <tgraf at suug.ch>
---
 lib/attr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/attr.c b/lib/attr.c
index 535f10c..e83aca2 100644
--- a/lib/attr.c
+++ b/lib/attr.c
@@ -192,7 +192,7 @@ static int validate_nla(struct nlattr *nla, int maxtype,
 	unsigned int minlen = 0;
 	int type = nla_type(nla);
 
-	if (type <= 0 || type > maxtype)
+	if (type < 0 || type > maxtype)
 		return 0;
 
 	pt = &policy[type];
-- 
1.8.3.1