netlink: allow extack cookie also for error messages

Commit ba0dc5f6e0 ("netlink: allow sending extended ACK with cookie on
success") introduced a cookie which can be sent to userspace as part of
extended ack message in the form of NLMSGERR_ATTR_COOKIE attribute.
Currently the cookie is ignored if error code is non-zero but there is
no technical reason for such limitation and it can be useful to provide
machine parseable information as part of an error message.

Include NLMSGERR_ATTR_COOKIE whenever the cookie has been set,
regardless of error code.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michal Kubecek 2020-03-15 18:17:43 +01:00 committed by David S. Miller
parent ef299cc3fa
commit fe2a31d790

View file

@ -2392,19 +2392,14 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
if (nlk_has_extack && extack && extack->_msg)
tlvlen += nla_total_size(strlen(extack->_msg) + 1);
if (err) {
if (!(nlk->flags & NETLINK_F_CAP_ACK))
payload += nlmsg_len(nlh);
else
flags |= NLM_F_CAPPED;
if (nlk_has_extack && extack && extack->bad_attr)
tlvlen += nla_total_size(sizeof(u32));
} else {
if (err && !(nlk->flags & NETLINK_F_CAP_ACK))
payload += nlmsg_len(nlh);
else
flags |= NLM_F_CAPPED;
if (nlk_has_extack && extack && extack->cookie_len)
tlvlen += nla_total_size(extack->cookie_len);
}
if (err && nlk_has_extack && extack && extack->bad_attr)
tlvlen += nla_total_size(sizeof(u32));
if (nlk_has_extack && extack && extack->cookie_len)
tlvlen += nla_total_size(extack->cookie_len);
if (tlvlen)
flags |= NLM_F_ACK_TLVS;
@ -2427,20 +2422,16 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err,
WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG,
extack->_msg));
}
if (err) {
if (extack->bad_attr &&
!WARN_ON((u8 *)extack->bad_attr < in_skb->data ||
(u8 *)extack->bad_attr >= in_skb->data +
in_skb->len))
WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS,
(u8 *)extack->bad_attr -
(u8 *)nlh));
} else {
if (extack->cookie_len)
WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE,
extack->cookie_len,
extack->cookie));
}
if (err && extack->bad_attr &&
!WARN_ON((u8 *)extack->bad_attr < in_skb->data ||
(u8 *)extack->bad_attr >= in_skb->data +
in_skb->len))
WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS,
(u8 *)extack->bad_attr -
(u8 *)nlh));
if (extack->cookie_len)
WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE,
extack->cookie_len, extack->cookie));
}
nlmsg_end(skb, rep);