diff options
| author | Zhongqiu Duan <dzq.aishenghu0@gmail.com> | 2025-04-17 15:49:30 +0000 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2025-05-05 13:15:09 +0200 |
| commit | bfe7cfb65c753952735c3eed703eba9a8b96a18d (patch) | |
| tree | dbf58bf06a1aaffc99637e07c7ba131e12e78d64 | |
| parent | d33f889fd80c91e0250874e910fc58918eb660db (diff) | |
netfilter: nft_quota: match correctly when the quota just depleted
The xt_quota compares skb length with remaining quota, but the nft_quota
compares it with consumed bytes.
The xt_quota can match consumed bytes up to quota at maximum. But the
nft_quota break match when consumed bytes equal to quota.
i.e., nft_quota match consumed bytes in [0, quota - 1], not [0, quota].
Fixes: 795595f68d6c ("netfilter: nft_quota: dump consumed quota")
Signed-off-by: Zhongqiu Duan <dzq.aishenghu0@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | net/netfilter/nft_quota.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/net/netfilter/nft_quota.c b/net/netfilter/nft_quota.c index 9b2d7463d3d3..df0798da2329 100644 --- a/net/netfilter/nft_quota.c +++ b/net/netfilter/nft_quota.c @@ -19,10 +19,16 @@ struct nft_quota { }; static inline bool nft_overquota(struct nft_quota *priv, - const struct sk_buff *skb) + const struct sk_buff *skb, + bool *report) { - return atomic64_add_return(skb->len, priv->consumed) >= - atomic64_read(&priv->quota); + u64 consumed = atomic64_add_return(skb->len, priv->consumed); + u64 quota = atomic64_read(&priv->quota); + + if (report) + *report = consumed >= quota; + + return consumed > quota; } static inline bool nft_quota_invert(struct nft_quota *priv) @@ -34,7 +40,7 @@ static inline void nft_quota_do_eval(struct nft_quota *priv, struct nft_regs *regs, const struct nft_pktinfo *pkt) { - if (nft_overquota(priv, pkt->skb) ^ nft_quota_invert(priv)) + if (nft_overquota(priv, pkt->skb, NULL) ^ nft_quota_invert(priv)) regs->verdict.code = NFT_BREAK; } @@ -51,13 +57,13 @@ static void nft_quota_obj_eval(struct nft_object *obj, const struct nft_pktinfo *pkt) { struct nft_quota *priv = nft_obj_data(obj); - bool overquota; + bool overquota, report; - overquota = nft_overquota(priv, pkt->skb); + overquota = nft_overquota(priv, pkt->skb, &report); if (overquota ^ nft_quota_invert(priv)) regs->verdict.code = NFT_BREAK; - if (overquota && + if (report && !test_and_set_bit(NFT_QUOTA_DEPLETED_BIT, &priv->flags)) nft_obj_notify(nft_net(pkt), obj->key.table, obj, 0, 0, NFT_MSG_NEWOBJ, 0, nft_pf(pkt), 0, GFP_ATOMIC); |