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-rw-r--r--net/netfilter/xt_recent.c64
1 files changed, 47 insertions, 17 deletions
diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c
index a9faae89f955..30dbe34915ae 100644
--- a/net/netfilter/xt_recent.c
+++ b/net/netfilter/xt_recent.c
@@ -43,25 +43,29 @@ MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_recent");
MODULE_ALIAS("ip6t_recent");
-static unsigned int ip_list_tot = 100;
-static unsigned int ip_pkt_list_tot = 20;
-static unsigned int ip_list_hash_size = 0;
-static unsigned int ip_list_perms = 0644;
-static unsigned int ip_list_uid = 0;
-static unsigned int ip_list_gid = 0;
+static unsigned int ip_list_tot __read_mostly = 100;
+static unsigned int ip_list_hash_size __read_mostly;
+static unsigned int ip_list_perms __read_mostly = 0644;
+static unsigned int ip_list_uid __read_mostly;
+static unsigned int ip_list_gid __read_mostly;
module_param(ip_list_tot, uint, 0400);
-module_param(ip_pkt_list_tot, uint, 0400);
module_param(ip_list_hash_size, uint, 0400);
module_param(ip_list_perms, uint, 0400);
module_param(ip_list_uid, uint, S_IRUGO | S_IWUSR);
module_param(ip_list_gid, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(ip_list_tot, "number of IPs to remember per list");
-MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 255)");
MODULE_PARM_DESC(ip_list_hash_size, "size of hash table used to look up IPs");
MODULE_PARM_DESC(ip_list_perms, "permissions on /proc/net/xt_recent/* files");
MODULE_PARM_DESC(ip_list_uid, "default owner of /proc/net/xt_recent/* files");
MODULE_PARM_DESC(ip_list_gid, "default owning group of /proc/net/xt_recent/* files");
+/* retained for backwards compatibility */
+static unsigned int ip_pkt_list_tot __read_mostly;
+module_param(ip_pkt_list_tot, uint, 0400);
+MODULE_PARM_DESC(ip_pkt_list_tot, "number of packets per IP address to remember (max. 255)");
+
+#define XT_RECENT_MAX_NSTAMPS 256
+
struct recent_entry {
struct list_head list;
struct list_head lru_list;
@@ -79,6 +83,7 @@ struct recent_table {
union nf_inet_addr mask;
unsigned int refcnt;
unsigned int entries;
+ u8 nstamps_max_mask;
struct list_head lru_list;
struct list_head iphash[0];
};
@@ -90,7 +95,8 @@ struct recent_net {
#endif
};
-static int recent_net_id;
+static int recent_net_id __read_mostly;
+
static inline struct recent_net *recent_pernet(struct net *net)
{
return net_generic(net, recent_net_id);
@@ -171,12 +177,15 @@ recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr,
u_int16_t family, u_int8_t ttl)
{
struct recent_entry *e;
+ unsigned int nstamps_max = t->nstamps_max_mask;
if (t->entries >= ip_list_tot) {
e = list_entry(t->lru_list.next, struct recent_entry, lru_list);
recent_entry_remove(t, e);
}
- e = kmalloc(sizeof(*e) + sizeof(e->stamps[0]) * ip_pkt_list_tot,
+
+ nstamps_max += 1;
+ e = kmalloc(sizeof(*e) + sizeof(e->stamps[0]) * nstamps_max,
GFP_ATOMIC);
if (e == NULL)
return NULL;
@@ -197,7 +206,7 @@ recent_entry_init(struct recent_table *t, const union nf_inet_addr *addr,
static void recent_entry_update(struct recent_table *t, struct recent_entry *e)
{
- e->index %= ip_pkt_list_tot;
+ e->index &= t->nstamps_max_mask;
e->stamps[e->index++] = jiffies;
if (e->index > e->nstamps)
e->nstamps = e->index;
@@ -326,6 +335,7 @@ static int recent_mt_check(const struct xt_mtchk_param *par,
kuid_t uid;
kgid_t gid;
#endif
+ unsigned int nstamp_mask;
unsigned int i;
int ret = -EINVAL;
size_t sz;
@@ -349,19 +359,33 @@ static int recent_mt_check(const struct xt_mtchk_param *par,
return -EINVAL;
if ((info->check_set & XT_RECENT_REAP) && !info->seconds)
return -EINVAL;
- if (info->hit_count > ip_pkt_list_tot) {
- pr_info("hitcount (%u) is larger than "
- "packets to be remembered (%u)\n",
- info->hit_count, ip_pkt_list_tot);
+ if (info->hit_count >= XT_RECENT_MAX_NSTAMPS) {
+ pr_info("hitcount (%u) is larger than allowed maximum (%u)\n",
+ info->hit_count, XT_RECENT_MAX_NSTAMPS - 1);
return -EINVAL;
}
if (info->name[0] == '\0' ||
strnlen(info->name, XT_RECENT_NAME_LEN) == XT_RECENT_NAME_LEN)
return -EINVAL;
+ if (ip_pkt_list_tot && info->hit_count < ip_pkt_list_tot)
+ nstamp_mask = roundup_pow_of_two(ip_pkt_list_tot) - 1;
+ else if (info->hit_count)
+ nstamp_mask = roundup_pow_of_two(info->hit_count) - 1;
+ else
+ nstamp_mask = 32 - 1;
+
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;
+ }
+
t->refcnt++;
ret = 0;
goto out;
@@ -377,6 +401,7 @@ static int recent_mt_check(const struct xt_mtchk_param *par,
goto out;
}
t->refcnt = 1;
+ t->nstamps_max_mask = nstamp_mask;
memcpy(&t->mask, &info->mask, sizeof(t->mask));
strcpy(t->name, info->name);
@@ -497,9 +522,12 @@ static void recent_seq_stop(struct seq_file *s, void *v)
static int recent_seq_show(struct seq_file *seq, void *v)
{
const struct recent_entry *e = v;
+ struct recent_iter_state *st = seq->private;
+ const struct recent_table *t = st->table;
unsigned int i;
- i = (e->index - 1) % ip_pkt_list_tot;
+ i = (e->index - 1) & t->nstamps_max_mask;
+
if (e->family == NFPROTO_IPV4)
seq_printf(seq, "src=%pI4 ttl: %u last_seen: %lu oldest_pkt: %u",
&e->addr.ip, e->ttl, e->stamps[i], e->index);
@@ -717,7 +745,9 @@ static int __init recent_mt_init(void)
{
int err;
- if (!ip_list_tot || !ip_pkt_list_tot || ip_pkt_list_tot > 255)
+ BUILD_BUG_ON_NOT_POWER_OF_2(XT_RECENT_MAX_NSTAMPS);
+
+ if (!ip_list_tot || ip_pkt_list_tot >= XT_RECENT_MAX_NSTAMPS)
return -EINVAL;
ip_list_hash_size = 1 << fls(ip_list_tot);