diff options
| author | Florian Westphal <fw@strlen.de> | 2023-10-11 09:59:38 +0200 |
|---|---|---|
| committer | Florian Westphal <fw@strlen.de> | 2023-10-18 10:26:43 +0200 |
| commit | e0d4593140b01b8da513a0c88c26da28b4906413 (patch) | |
| tree | 38aa2be18abfbdb974535a1530910a8b6c25cca2 /include/linux/netfilter.h | |
| parent | 35c038b0a4be197679deefaf96998241cb7efc88 (diff) | |
netfilter: make nftables drops visible in net dropmonitor
net_dropmonitor blames core.c:nf_hook_slow.
Add NF_DROP_REASON() helper and use it in nft_do_chain().
The helper releases the skb, so exact drop location becomes
available. Calling code will observe the NF_STOLEN verdict
instead.
Adjust nf_hook_slow so we can embed an erro value wih
NF_STOLEN verdicts, just like we do for NF_DROP.
After this, drop in nftables can be pinpointed to a drop due
to a rule or the chain policy.
Signed-off-by: Florian Westphal <fw@strlen.de>
Diffstat (limited to 'include/linux/netfilter.h')
| -rw-r--r-- | include/linux/netfilter.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index d68644b7c299..80900d910992 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -22,6 +22,16 @@ static inline int NF_DROP_GETERR(int verdict) return -(verdict >> NF_VERDICT_QBITS); } +static __always_inline int +NF_DROP_REASON(struct sk_buff *skb, enum skb_drop_reason reason, u32 err) +{ + BUILD_BUG_ON(err > 0xffff); + + kfree_skb_reason(skb, reason); + + return ((err << 16) | NF_STOLEN); +} + static inline int nf_inet_addr_cmp(const union nf_inet_addr *a1, const union nf_inet_addr *a2) { |