diff options
| -rw-r--r-- | include/net/netfilter/nf_conntrack_l4proto.h | 3 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 49 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_proto_dccp.c | 16 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_proto_sctp.c | 16 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_proto_tcp.c | 18 |
5 files changed, 102 insertions, 0 deletions
diff --git a/include/net/netfilter/nf_conntrack_l4proto.h b/include/net/netfilter/nf_conntrack_l4proto.h index 85e993e278d5..7032e044bbe2 100644 --- a/include/net/netfilter/nf_conntrack_l4proto.h +++ b/include/net/netfilter/nf_conntrack_l4proto.h @@ -58,6 +58,9 @@ struct nf_conntrack_l4proto { unsigned int dataoff, u_int8_t pf, unsigned int hooknum); + /* called by gc worker if table is full */ + bool (*can_early_drop)(const struct nf_conn *ct); + /* Print out the per-protocol part of the tuple. Return like seq_* */ void (*print_tuple)(struct seq_file *s, const struct nf_conntrack_tuple *); diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 62368b05cef5..f9245dbfe435 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -76,6 +76,7 @@ struct conntrack_gc_work { struct delayed_work dwork; u32 last_bucket; bool exiting; + bool early_drop; long next_gc_run; }; @@ -951,10 +952,30 @@ static noinline int early_drop(struct net *net, unsigned int _hash) return false; } +static bool gc_worker_skip_ct(const struct nf_conn *ct) +{ + return !nf_ct_is_confirmed(ct) || nf_ct_is_dying(ct); +} + +static bool gc_worker_can_early_drop(const struct nf_conn *ct) +{ + const struct nf_conntrack_l4proto *l4proto; + + if (!test_bit(IPS_ASSURED_BIT, &ct->status)) + return true; + + l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct)); + if (l4proto->can_early_drop && l4proto->can_early_drop(ct)) + return true; + + return false; +} + static void gc_worker(struct work_struct *work) { unsigned int min_interval = max(HZ / GC_MAX_BUCKETS_DIV, 1u); unsigned int i, goal, buckets = 0, expired_count = 0; + unsigned int nf_conntrack_max95 = 0; struct conntrack_gc_work *gc_work; unsigned int ratio, scanned = 0; unsigned long next_run; @@ -963,6 +984,8 @@ static void gc_worker(struct work_struct *work) goal = nf_conntrack_htable_size / GC_MAX_BUCKETS_DIV; i = gc_work->last_bucket; + if (gc_work->early_drop) + nf_conntrack_max95 = nf_conntrack_max / 100u * 95u; do { struct nf_conntrack_tuple_hash *h; @@ -979,6 +1002,8 @@ static void gc_worker(struct work_struct *work) i = 0; hlist_nulls_for_each_entry_rcu(h, n, &ct_hash[i], hnnode) { + struct net *net; + tmp = nf_ct_tuplehash_to_ctrack(h); scanned++; @@ -987,6 +1012,27 @@ static void gc_worker(struct work_struct *work) expired_count++; continue; } + + if (nf_conntrack_max95 == 0 || gc_worker_skip_ct(tmp)) + continue; + + net = nf_ct_net(tmp); + if (atomic_read(&net->ct.count) < nf_conntrack_max95) + continue; + + /* need to take reference to avoid possible races */ + if (!atomic_inc_not_zero(&tmp->ct_general.use)) + continue; + + if (gc_worker_skip_ct(tmp)) { + nf_ct_put(tmp); + continue; + } + + if (gc_worker_can_early_drop(tmp)) + nf_ct_kill(tmp); + + nf_ct_put(tmp); } /* could check get_nulls_value() here and restart if ct @@ -1032,6 +1078,7 @@ static void gc_worker(struct work_struct *work) next_run = gc_work->next_gc_run; gc_work->last_bucket = i; + gc_work->early_drop = false; queue_delayed_work(system_long_wq, &gc_work->dwork, next_run); } @@ -1057,6 +1104,8 @@ __nf_conntrack_alloc(struct net *net, if (nf_conntrack_max && unlikely(atomic_read(&net->ct.count) > nf_conntrack_max)) { if (!early_drop(net, hash)) { + if (!conntrack_gc_work.early_drop) + conntrack_gc_work.early_drop = true; atomic_dec(&net->ct.count); net_warn_ratelimited("nf_conntrack: table full, dropping packet\n"); return ERR_PTR(-ENOMEM); diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c index 93dd1c5b7bff..4b3b6e1cadc9 100644 --- a/net/netfilter/nf_conntrack_proto_dccp.c +++ b/net/netfilter/nf_conntrack_proto_dccp.c @@ -609,6 +609,20 @@ out_invalid: return -NF_ACCEPT; } +static bool dccp_can_early_drop(const struct nf_conn *ct) +{ + switch (ct->proto.dccp.state) { + case CT_DCCP_CLOSEREQ: + case CT_DCCP_CLOSING: + case CT_DCCP_TIMEWAIT: + return true; + default: + break; + } + + return false; +} + static void dccp_print_tuple(struct seq_file *s, const struct nf_conntrack_tuple *tuple) { @@ -868,6 +882,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp4 __read_mostly = { .packet = dccp_packet, .get_timeouts = dccp_get_timeouts, .error = dccp_error, + .can_early_drop = dccp_can_early_drop, .print_tuple = dccp_print_tuple, .print_conntrack = dccp_print_conntrack, #if IS_ENABLED(CONFIG_NF_CT_NETLINK) @@ -902,6 +917,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp6 __read_mostly = { .packet = dccp_packet, .get_timeouts = dccp_get_timeouts, .error = dccp_error, + .can_early_drop = dccp_can_early_drop, .print_tuple = dccp_print_tuple, .print_conntrack = dccp_print_conntrack, #if IS_ENABLED(CONFIG_NF_CT_NETLINK) diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 33279aab583d..b34b49c59a1c 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -535,6 +535,20 @@ out_invalid: return -NF_ACCEPT; } +static bool sctp_can_early_drop(const struct nf_conn *ct) +{ + switch (ct->proto.sctp.state) { + case SCTP_CONNTRACK_SHUTDOWN_SENT: + case SCTP_CONNTRACK_SHUTDOWN_RECD: + case SCTP_CONNTRACK_SHUTDOWN_ACK_SENT: + return true; + default: + break; + } + + return false; +} + #if IS_ENABLED(CONFIG_NF_CT_NETLINK) #include <linux/netfilter/nfnetlink.h> @@ -783,6 +797,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = { .get_timeouts = sctp_get_timeouts, .new = sctp_new, .error = sctp_error, + .can_early_drop = sctp_can_early_drop, .me = THIS_MODULE, #if IS_ENABLED(CONFIG_NF_CT_NETLINK) .to_nlattr = sctp_to_nlattr, @@ -818,6 +833,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 __read_mostly = { .get_timeouts = sctp_get_timeouts, .new = sctp_new, .error = sctp_error, + .can_early_drop = sctp_can_early_drop, .me = THIS_MODULE, #if IS_ENABLED(CONFIG_NF_CT_NETLINK) .to_nlattr = sctp_to_nlattr, diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index b122e9dacfed..d0c0a31dfe74 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -1172,6 +1172,22 @@ static bool tcp_new(struct nf_conn *ct, const struct sk_buff *skb, return true; } +static bool tcp_can_early_drop(const struct nf_conn *ct) +{ + switch (ct->proto.tcp.state) { + case TCP_CONNTRACK_FIN_WAIT: + case TCP_CONNTRACK_LAST_ACK: + case TCP_CONNTRACK_TIME_WAIT: + case TCP_CONNTRACK_CLOSE: + case TCP_CONNTRACK_CLOSE_WAIT: + return true; + default: + break; + } + + return false; +} + #if IS_ENABLED(CONFIG_NF_CT_NETLINK) #include <linux/netfilter/nfnetlink.h> @@ -1549,6 +1565,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp4 __read_mostly = .get_timeouts = tcp_get_timeouts, .new = tcp_new, .error = tcp_error, + .can_early_drop = tcp_can_early_drop, #if IS_ENABLED(CONFIG_NF_CT_NETLINK) .to_nlattr = tcp_to_nlattr, .nlattr_size = tcp_nlattr_size, @@ -1586,6 +1603,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp6 __read_mostly = .get_timeouts = tcp_get_timeouts, .new = tcp_new, .error = tcp_error, + .can_early_drop = tcp_can_early_drop, #if IS_ENABLED(CONFIG_NF_CT_NETLINK) .to_nlattr = tcp_to_nlattr, .nlattr_size = tcp_nlattr_size, |