netfilter: nf_tables: fix inconsistent element expiration calculation

As Liping Zhang reports, after commit a8b1e36d0d1d ("netfilter: nft_dynset:
fix element timeout for HZ != 1000"), priv->timeout was stored in jiffies,
while set->timeout was stored in milliseconds. This is inconsistent and
incorrect.

Firstly, we already call msecs_to_jiffies in nft_set_elem_init, so
priv->timeout will be converted to jiffies twice.

Secondly, if the user did not specify the NFTA_DYNSET_TIMEOUT attr,
set->timeout will be used, but we forget to call msecs_to_jiffies
when do update elements.

Fix this by using jiffies internally for traditional sets and doing the
conversions to/from msec when interacting with userspace - as dynset
already does.

This is preferable to doing the conversions, when elements are inserted or
updated, because this can happen very frequently on busy dynsets.

Fixes: a8b1e36d0d1d ("netfilter: nft_dynset: fix element timeout for HZ != 1000")
Reported-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Anders K. Pedersen <akp@cohaesio.com>
Acked-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index d79d1e9b95461bc869c6149f80d7e3789bcb89ac..b02af0bf577796687c457bb10def12d959019cb0 100644 (file)
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -313,7 +313,7 @@ void nft_unregister_set(struct nft_set_ops *ops);
  *     @size: maximum set size
  *     @nelems: number of elements
  *     @ndeact: number of deactivated elements queued for removal
- *     @timeout: default timeout value in msecs
+ *     @timeout: default timeout value in jiffies
  *     @gc_int: garbage collection interval in msecs
  *     @policy: set parameterization (see enum nft_set_policies)
  *     @udlen: user data length

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 026581b04ea8d16b805183332ce216aac9c36ebc..e5194f6f906cb28396620917968aae42fb0872b2 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2570,7 +2570,8 @@ static int nf_tables_fill_set(struct sk_buff *skb, const struct nft_ctx *ctx,
        }
 
        if (set->timeout &&
-           nla_put_be64(skb, NFTA_SET_TIMEOUT, cpu_to_be64(set->timeout),
+           nla_put_be64(skb, NFTA_SET_TIMEOUT,
+                        cpu_to_be64(jiffies_to_msecs(set->timeout)),
                         NFTA_SET_PAD))
                goto nla_put_failure;
        if (set->gc_int &&
@@ -2859,7 +2860,8 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
        if (nla[NFTA_SET_TIMEOUT] != NULL) {
                if (!(flags & NFT_SET_TIMEOUT))
                        return -EINVAL;
-               timeout = be64_to_cpu(nla_get_be64(nla[NFTA_SET_TIMEOUT]));
+               timeout = msecs_to_jiffies(be64_to_cpu(nla_get_be64(
+                                               nla[NFTA_SET_TIMEOUT])));
        }
        gc_int = 0;
        if (nla[NFTA_SET_GC_INTERVAL] != NULL) {
@@ -3178,7 +3180,8 @@ static int nf_tables_fill_setelem(struct sk_buff *skb,
 
        if (nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT) &&
            nla_put_be64(skb, NFTA_SET_ELEM_TIMEOUT,
-                        cpu_to_be64(*nft_set_ext_timeout(ext)),
+                        cpu_to_be64(jiffies_to_msecs(
+                                               *nft_set_ext_timeout(ext))),
                         NFTA_SET_ELEM_PAD))
                goto nla_put_failure;
 
@@ -3447,7 +3450,7 @@ void *nft_set_elem_init(const struct nft_set *set,
                memcpy(nft_set_ext_data(ext), data, set->dlen);
        if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPIRATION))
                *nft_set_ext_expiration(ext) =
-                       jiffies + msecs_to_jiffies(timeout);
+                       jiffies + timeout;
        if (nft_set_ext_exists(ext, NFT_SET_EXT_TIMEOUT))
                *nft_set_ext_timeout(ext) = timeout;
 
@@ -3535,7 +3538,8 @@ static int nft_add_set_elem(struct nft_ctx *ctx, struct nft_set *set,
        if (nla[NFTA_SET_ELEM_TIMEOUT] != NULL) {
                if (!(set->flags & NFT_SET_TIMEOUT))
                        return -EINVAL;
-               timeout = be64_to_cpu(nla_get_be64(nla[NFTA_SET_ELEM_TIMEOUT]));
+               timeout = msecs_to_jiffies(be64_to_cpu(nla_get_be64(
+                                       nla[NFTA_SET_ELEM_TIMEOUT])));
        } else if (set->flags & NFT_SET_TIMEOUT) {
                timeout = set->timeout;
        }