diff options
Diffstat (limited to 'net/netfilter/nft_limit.c')
| -rw-r--r-- | net/netfilter/nft_limit.c | 25 |
1 files changed, 14 insertions, 11 deletions
diff --git a/net/netfilter/nft_limit.c b/net/netfilter/nft_limit.c index 18dd57a52651..14538b1d4d11 100644 --- a/net/netfilter/nft_limit.c +++ b/net/netfilter/nft_limit.c @@ -65,19 +65,23 @@ static int nft_limit_init(struct nft_limit *limit, limit->nsecs = unit * NSEC_PER_SEC; if (limit->rate == 0 || limit->nsecs < unit) return -EOVERFLOW; - limit->tokens = limit->tokens_max = limit->nsecs; - - if (tb[NFTA_LIMIT_BURST]) { - u64 rate; + if (tb[NFTA_LIMIT_BURST]) limit->burst = ntohl(nla_get_be32(tb[NFTA_LIMIT_BURST])); + else + limit->burst = 0; + + if (limit->rate + limit->burst < limit->rate) + return -EOVERFLOW; - rate = limit->rate + limit->burst; - if (rate < limit->rate) - return -EOVERFLOW; + /* The token bucket size limits the number of tokens can be + * accumulated. tokens_max specifies the bucket size. + * tokens_max = unit * (rate + burst) / rate. + */ + limit->tokens = div_u64(limit->nsecs * (limit->rate + limit->burst), + limit->rate); + limit->tokens_max = limit->tokens; - limit->rate = rate; - } if (tb[NFTA_LIMIT_FLAGS]) { u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS])); @@ -95,9 +99,8 @@ static int nft_limit_dump(struct sk_buff *skb, const struct nft_limit *limit, { u32 flags = limit->invert ? NFT_LIMIT_F_INV : 0; u64 secs = div_u64(limit->nsecs, NSEC_PER_SEC); - u64 rate = limit->rate - limit->burst; - if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(rate), + if (nla_put_be64(skb, NFTA_LIMIT_RATE, cpu_to_be64(limit->rate), NFTA_LIMIT_PAD) || nla_put_be64(skb, NFTA_LIMIT_UNIT, cpu_to_be64(secs), NFTA_LIMIT_PAD) || |