diff options
| author | Jesper Dangaard Brouer <hawk@comx.dk> | 2010-04-23 12:34:56 +0200 |
|---|---|---|
| committer | Patrick McHardy <kaber@trash.net> | 2010-04-23 12:34:56 +0200 |
| commit | af740b2c8f4521e2c45698ee6040941a82d6349d (patch) | |
| tree | ae9fb87ebbfd422b07cb8e027fbe13e9c40c403e | |
| parent | cecc74de25d2cfb08e7702cd38e3f195950f1228 (diff) | |
netfilter: nf_conntrack: extend with extra stat counter
I suspect an unfortunatly series of events occuring under a DDoS
attack, in function __nf_conntrack_find() nf_contrack_core.c.
Adding a stats counter to see if the search is restarted too often.
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
| -rw-r--r-- | include/linux/netfilter/nf_conntrack_common.h | 1 | ||||
| -rw-r--r-- | net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c | 7 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 4 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_standalone.c | 7 |
4 files changed, 12 insertions, 7 deletions
diff --git a/include/linux/netfilter/nf_conntrack_common.h b/include/linux/netfilter/nf_conntrack_common.h index c608677dda60..14e6d32002c4 100644 --- a/include/linux/netfilter/nf_conntrack_common.h +++ b/include/linux/netfilter/nf_conntrack_common.h @@ -113,6 +113,7 @@ struct ip_conntrack_stat { unsigned int expect_new; unsigned int expect_create; unsigned int expect_delete; + unsigned int search_restart; }; /* call to create an explicit dependency on nf_conntrack. */ diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c index 2fb7b76da94f..244f7cb08d68 100644 --- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c +++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4_compat.c @@ -336,12 +336,12 @@ static int ct_cpu_seq_show(struct seq_file *seq, void *v) const struct ip_conntrack_stat *st = v; if (v == SEQ_START_TOKEN) { - seq_printf(seq, "entries searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error expect_new expect_create expect_delete\n"); + seq_printf(seq, "entries searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error expect_new expect_create expect_delete search_restart\n"); return 0; } seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x " - "%08x %08x %08x %08x %08x %08x %08x %08x \n", + "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n", nr_conntracks, st->searched, st->found, @@ -358,7 +358,8 @@ static int ct_cpu_seq_show(struct seq_file *seq, void *v) st->expect_new, st->expect_create, - st->expect_delete + st->expect_delete, + st->search_restart ); return 0; } diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 0c9bbe93cc16..3907efb97a7c 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -319,8 +319,10 @@ begin: * not the expected one, we must restart lookup. * We probably met an item that was moved to another chain. */ - if (get_nulls_value(n) != hash) + if (get_nulls_value(n) != hash) { + NF_CT_STAT_INC(net, search_restart); goto begin; + } local_bh_enable(); return NULL; diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c index faa8eb3722b9..ea4a8d384234 100644 --- a/net/netfilter/nf_conntrack_standalone.c +++ b/net/netfilter/nf_conntrack_standalone.c @@ -252,12 +252,12 @@ static int ct_cpu_seq_show(struct seq_file *seq, void *v) const struct ip_conntrack_stat *st = v; if (v == SEQ_START_TOKEN) { - seq_printf(seq, "entries searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error expect_new expect_create expect_delete\n"); + seq_printf(seq, "entries searched found new invalid ignore delete delete_list insert insert_failed drop early_drop icmp_error expect_new expect_create expect_delete search_restart\n"); return 0; } seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x " - "%08x %08x %08x %08x %08x %08x %08x %08x \n", + "%08x %08x %08x %08x %08x %08x %08x %08x %08x\n", nr_conntracks, st->searched, st->found, @@ -274,7 +274,8 @@ static int ct_cpu_seq_show(struct seq_file *seq, void *v) st->expect_new, st->expect_create, - st->expect_delete + st->expect_delete, + st->search_restart ); return 0; } |