summaryrefslogtreecommitdiff
path: root/net/netfilter
diff options
context:
space:
mode:
authorFlorian Westphal <fw@strlen.de>2015-02-13 12:47:50 +0100
committerPablo Neira Ayuso <pablo@netfilter.org>2015-02-16 17:00:47 +0100
commitcef9ed86ed62eeffcd017882278bbece32001f86 (patch)
tree8f41fb1c365d88e1a1cd3e772e21534868bd82c9 /net/netfilter
parent520aa7414bb590f39d0d1591b06018e60cbc7cf4 (diff)
netfilter: xt_recent: don't reject rule if new hitcount exceeds table max
given: -A INPUT -m recent --update --seconds 30 --hitcount 4 and iptables-save > foo then iptables-restore < foo will fail with: kernel: xt_recent: hitcount (4) is larger than packets to be remembered (4) for table DEFAULT Even when the check is fixed, the restore won't work if the hitcount is increased to e.g. 6, since by the time checkentry runs it will find the 'old' incarnation of the table. We can avoid this by increasing the maximum threshold silently; we only have to rm all the current entries of the table (these entries would not have enough room to handle the increased hitcount). This even makes (not-very-useful) -A INPUT -m recent --update --seconds 30 --hitcount 4 -A INPUT -m recent --update --seconds 30 --hitcount 42 work. Fixes: abc86d0f99242b7f142b (netfilter: xt_recent: relax ip_pkt_list_tot restrictions) Tracked-down-by: Chris Vine <chris@cvine.freeserve.co.uk> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter')
-rw-r--r--net/netfilter/xt_recent.c11
1 files changed, 5 insertions, 6 deletions
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index 30dbe34915ae..45e1b30e4fb2 100644
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -378,12 +378,11 @@ static int recent_mt_check(const struct xt_mtchk_param *par,
mutex_lock(&recent_mutex);
t = recent_table_lookup(recent_net, info->name);
if (t != NULL) {
- if (info->hit_count > t->nstamps_max_mask) {
- pr_info("hitcount (%u) is larger than packets to be remembered (%u) for table %s\n",
- info->hit_count, t->nstamps_max_mask + 1,
- info->name);
- ret = -EINVAL;
- goto out;
+ if (nstamp_mask > t->nstamps_max_mask) {
+ spin_lock_bh(&recent_lock);
+ recent_table_flush(t);
+ t->nstamps_max_mask = nstamp_mask;
+ spin_unlock_bh(&recent_lock);
}
t->refcnt++;