[PATCHv2 net-next 02/15] lib: nlattr: set extack msg if validate_nla fails

[Alexander Aring <aring@mojatatu.com>]

This patch sets a generic netlink error message if the validation of the
netlink attribute failed. It avoids several different settings of
netlink messages by handle nla_parse_nested on error case.

Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
---
 lib/nlattr.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/nlattr.c b/lib/nlattr.c
index dfa55c873c13..a2a9506b2fb7 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c
@@ -253,8 +253,10 @@ int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head,
 			if (policy) {
 				err = validate_nla(nla, maxtype, policy);
 				if (err < 0) {
-					if (extack)
+					if (extack) {
+						NL_SET_ERR_MSG(extack, "Failed to validate netlink attribute");
 						extack->bad_attr = nla;
+					}
 					goto errout;
 				}
 			}
-- 
2.11.0