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- --- a/net/ipv4/netfilter/ip_tables.c
- +++ b/net/ipv4/netfilter/ip_tables.c
- @@ -308,6 +308,33 @@ struct ipt_entry *ipt_next_entry(const s
- return (void *)entry + entry->next_offset;
- }
-
- +static bool
- +ipt_handle_default_rule(struct ipt_entry *e, unsigned int *verdict)
- +{
- + struct xt_entry_target *t;
- + struct xt_standard_target *st;
- +
- + if (e->target_offset != sizeof(struct ipt_entry))
- + return false;
- +
- + if (!(e->ip.flags & IPT_F_NO_DEF_MATCH))
- + return false;
- +
- + t = ipt_get_target(e);
- + if (t->u.kernel.target->target)
- + return false;
- +
- + st = (struct xt_standard_target *) t;
- + if (st->verdict == XT_RETURN)
- + return false;
- +
- + if (st->verdict >= 0)
- + return false;
- +
- + *verdict = (unsigned)(-st->verdict) - 1;
- + return true;
- +}
- +
- /* Returns one of the generic firewall policies, like NF_ACCEPT. */
- unsigned int
- ipt_do_table(struct sk_buff *skb,
- @@ -328,28 +355,8 @@ ipt_do_table(struct sk_buff *skb,
- unsigned int addend;
-
- /* Initialization */
- - stackidx = 0;
- - ip = ip_hdr(skb);
- - indev = state->in ? state->in->name : nulldevname;
- - outdev = state->out ? state->out->name : nulldevname;
- - /* We handle fragments by dealing with the first fragment as
- - * if it was a normal packet. All other fragments are treated
- - * normally, except that they will NEVER match rules that ask
- - * things we don't know, ie. tcp syn flag or ports). If the
- - * rule is also a fragment-specific rule, non-fragments won't
- - * match it. */
- - acpar.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
- - acpar.thoff = ip_hdrlen(skb);
- - acpar.hotdrop = false;
- - acpar.net = state->net;
- - acpar.in = state->in;
- - acpar.out = state->out;
- - acpar.family = NFPROTO_IPV4;
- - acpar.hooknum = hook;
- -
- IP_NF_ASSERT(table->valid_hooks & (1 << hook));
- local_bh_disable();
- - addend = xt_write_recseq_begin();
- private = table->private;
- cpu = smp_processor_id();
- /*
- @@ -358,6 +365,23 @@ ipt_do_table(struct sk_buff *skb,
- */
- smp_read_barrier_depends();
- table_base = private->entries;
- +
- + e = get_entry(table_base, private->hook_entry[hook]);
- + if (ipt_handle_default_rule(e, &verdict)) {
- + struct xt_counters *counter;
- +
- + counter = xt_get_this_cpu_counter(&e->counters);
- + ADD_COUNTER(*counter, skb->len, 1);
- + local_bh_enable();
- + return verdict;
- + }
- +
- + stackidx = 0;
- + ip = ip_hdr(skb);
- + indev = state->in ? state->in->name : nulldevname;
- + outdev = state->out ? state->out->name : nulldevname;
- +
- + addend = xt_write_recseq_begin();
- jumpstack = (struct ipt_entry **)private->jumpstack[cpu];
-
- /* Switch to alternate jumpstack if we're being invoked via TEE.
- @@ -370,7 +394,20 @@ ipt_do_table(struct sk_buff *skb,
- if (static_key_false(&xt_tee_enabled))
- jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated);
-
- - e = get_entry(table_base, private->hook_entry[hook]);
- + /* We handle fragments by dealing with the first fragment as
- + * if it was a normal packet. All other fragments are treated
- + * normally, except that they will NEVER match rules that ask
- + * things we don't know, ie. tcp syn flag or ports). If the
- + * rule is also a fragment-specific rule, non-fragments won't
- + * match it. */
- + acpar.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
- + acpar.thoff = ip_hdrlen(skb);
- + acpar.hotdrop = false;
- + acpar.net = state->net;
- + acpar.in = state->in;
- + acpar.out = state->out;
- + acpar.family = NFPROTO_IPV4;
- + acpar.hooknum = hook;
-
- pr_debug("Entering %s(hook %u), UF %p\n",
- table->name, hook,
|
