diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2020-10-08 12:45:17 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-10-09 20:22:32 -0700 |
| commit | 44f3625bc61653ea3bde9960298faf2f5518fda5 (patch) | |
| tree | e36d5d8e5795a8992618cc2f756c5bc38d977434 /net/netlink/af_netlink.c | |
| parent | d2681e93b0ab7afe01d07f8c96f14afaccdcea4c (diff) | |
| download | linux-44f3625bc61653ea3bde9960298faf2f5518fda5.tar.gz | |
netlink: export policy in extended ACK
Add a new attribute NLMSGERR_ATTR_POLICY to the extended ACK
to advertise the policy, e.g. if an attribute was out of range,
you'll know the range that's permissible.
Add new NL_SET_ERR_MSG_ATTR_POL() and NL_SET_ERR_MSG_ATTR_POL()
macros to set this, since realistically it's only useful to do
this when the bad attribute (offset) is also returned.
Use it in lib/nlattr.c which practically does all the policy
validation.
v2:
- add and use netlink_policy_dump_attr_size_estimate()
v3:
- remove redundant break
v4:
- really remove redundant break ... sorry
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/netlink/af_netlink.c')
| -rw-r--r-- | net/netlink/af_netlink.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index df675a8e19188e..daca50d6bb1283 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2420,6 +2420,8 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, tlvlen += nla_total_size(sizeof(u32)); if (nlk_has_extack && extack && extack->cookie_len) tlvlen += nla_total_size(extack->cookie_len); + if (err && nlk_has_extack && extack && extack->policy) + tlvlen += netlink_policy_dump_attr_size_estimate(extack->policy); if (tlvlen) flags |= NLM_F_ACK_TLVS; @@ -2452,6 +2454,9 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, if (extack->cookie_len) WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE, extack->cookie_len, extack->cookie)); + if (extack->policy) + netlink_policy_dump_write_attr(skb, extack->policy, + NLMSGERR_ATTR_POLICY); } nlmsg_end(skb, rep); |