diff options
Diffstat (limited to 'pkgs/patches-linux-5.15/611-netfilter_match_bypass_default_table.patch')
| -rw-r--r-- | pkgs/patches-linux-5.15/611-netfilter_match_bypass_default_table.patch | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/pkgs/patches-linux-5.15/611-netfilter_match_bypass_default_table.patch b/pkgs/patches-linux-5.15/611-netfilter_match_bypass_default_table.patch new file mode 100644 index 0000000..baf738a --- /dev/null +++ b/pkgs/patches-linux-5.15/611-netfilter_match_bypass_default_table.patch @@ -0,0 +1,106 @@ +From: Felix Fietkau <nbd@nbd.name> +Subject: netfilter: match bypass default table + +Signed-off-by: Felix Fietkau <nbd@nbd.name> +--- + net/ipv4/netfilter/ip_tables.c | 79 +++++++++++++++++++++++++++++++----------- + 1 file changed, 58 insertions(+), 21 deletions(-) + +--- a/net/ipv4/netfilter/ip_tables.c ++++ b/net/ipv4/netfilter/ip_tables.c +@@ -246,6 +246,33 @@ 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, +@@ -266,27 +293,28 @@ ipt_do_table(struct sk_buff *skb, + unsigned int addend; + + /* Initialization */ ++ WARN_ON(!(table->valid_hooks & (1 << hook))); ++ local_bh_disable(); ++ private = READ_ONCE(table->private); /* Address dependency. */ ++ cpu = smp_processor_id(); ++ 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; +- /* 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.state = state; + +- WARN_ON(!(table->valid_hooks & (1 << hook))); +- local_bh_disable(); + addend = xt_write_recseq_begin(); +- private = READ_ONCE(table->private); /* Address dependency. */ +- cpu = smp_processor_id(); +- table_base = private->entries; + jumpstack = (struct ipt_entry **)private->jumpstack[cpu]; + + /* Switch to alternate jumpstack if we're being invoked via TEE. +@@ -299,7 +327,16 @@ 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.state = state; + + do { + const struct xt_entry_target *t; |