@@ -2,6 +2,7 @@ From: Felix Fietkau <nbd@nbd.name>
Subject: netfilter: optional tcp window check
Signed-off-by: Felix Fietkau <nbd@nbd.name>
+Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@gmail.com>
---
net/netfilter/nf_conntrack_proto_tcp.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
@@ -12,68 +13,71 @@ Signed-off-by: Felix Fietkau <nbd@nbd.name>
s32 receiver_offset;
bool res, in_recv_win;
-+ if (net->ct.sysctl_no_window_check)
++ if (tn->tcp_no_window_check)
+ return true;
+
/*
* Get the required data from the packet.
*/
-@@ -1160,7 +1163,7 @@ int nf_conntrack_tcp_packet(struct nf_co
+@@ -1151,7 +1154,7 @@ int nf_conntrack_tcp_packet(struct nf_co
IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED &&
timeouts[new_state] > timeouts[TCP_CONNTRACK_UNACK])
timeout = timeouts[TCP_CONNTRACK_UNACK];
- else if (ct->proto.tcp.last_win == 0 &&
-+ else if (!net->ct.sysctl_no_window_check && ct->proto.tcp.last_win == 0 &&
++ else if (!tn->tcp_no_window_check && ct->proto.tcp.last_win == 0 &&
timeouts[new_state] > timeouts[TCP_CONNTRACK_RETRANS])
timeout = timeouts[TCP_CONNTRACK_RETRANS];
else
+@@ -1451,6 +1454,9 @@ int nf_conntrack_tcp_packet(struct nf_co
+ * If it's non-zero, we mark only out of window RST segments as INVALID.
+ */
+ tn->tcp_be_liberal = 0;
++
++ /* Skip Windows Check */
++ tn->tcp_no_window_check = 0;
+
+ /* If it's non-zero, we turn off RST sequence number check */
+ tn->tcp_ignore_invalid_rst = 0;
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -671,6 +671,7 @@ enum nf_ct_sysctl_index {
- NF_SYSCTL_CT_LWTUNNEL,
#endif
-
+ NF_SYSCTL_CT_PROTO_TCP_LOOSE,
+ NF_SYSCTL_CT_PROTO_TCP_LIBERAL,
+ NF_SYSCTL_CT_PROTO_TCP_NO_WINDOW_CHECK,
- __NF_SYSCTL_CT_LAST_SYSCTL,
- };
-
-@@ -1026,6 +1027,13 @@ static struct ctl_table nf_ct_sysctl_tab
- .proc_handler = nf_hooks_lwtunnel_sysctl_handler,
+ NF_SYSCTL_CT_PROTO_TCP_IGNORE_INVALID_RST,
+ NF_SYSCTL_CT_PROTO_TCP_MAX_RETRANS,
+ NF_SYSCTL_CT_PROTO_TIMEOUT_UDP,
+@@ -800,6 +800,14 @@ static struct ctl_table nf_ct_sysctl_tab
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
},
- #endif
+ [NF_SYSCTL_CT_PROTO_TCP_NO_WINDOW_CHECK] = {
+ .procname = "nf_conntrack_tcp_no_window_check",
-+ .data = &init_net.ct.sysctl_no_window_check,
-+ .maxlen = sizeof(unsigned int),
++ .maxlen = sizeof(u8),
+ .mode = 0644,
-+ .proc_handler = proc_dointvec,
++ .proc_handler = proc_dou8vec_minmax,
++ .extra1 = SYSCTL_ZERO,
++ .extra2 = SYSCTL_ONE,
+ },
- {}
- };
+ [NF_SYSCTL_CT_PROTO_TCP_IGNORE_INVALID_RST] = {
+ .procname = "nf_conntrack_tcp_ignore_invalid_rst",
+ .maxlen = sizeof(u8),
+@@ -900,6 +900,7 @@ static int nf_conntrack_standalone_init_
-@@ -1153,6 +1161,7 @@ static int nf_conntrack_standalone_init_
- #ifdef CONFIG_NF_CONNTRACK_EVENTS
- table[NF_SYSCTL_CT_EVENTS].data = &net->ct.sysctl_events;
- #endif
-+ table[NF_SYSCTL_CT_PROTO_TCP_NO_WINDOW_CHECK].data = &net->ct.sysctl_no_window_check;
- #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
- table[NF_SYSCTL_CT_TIMESTAMP].data = &net->ct.sysctl_tstamp;
- #endif
-@@ -1222,6 +1231,7 @@ static int nf_conntrack_pernet_init(stru
- int ret;
-
- net->ct.sysctl_checksum = 1;
-+ net->ct.sysctl_no_window_check = 1;
-
- ret = nf_conntrack_standalone_init_sysctl(net);
- if (ret < 0)
+ XASSIGN(LOOSE, &tn->tcp_loose);
+ XASSIGN(LIBERAL, &tn->tcp_be_liberal);
++ XASSIGN(NO_WINDOW_CHECK, &tn->tcp_no_window_check);
+ XASSIGN(MAX_RETRANS, &tn->tcp_max_retrans);
+ XASSIGN(IGNORE_INVALID_RST, &tn->tcp_ignore_invalid_rst);
+ #undef XASSIGN
--- a/include/net/netns/conntrack.h
+++ b/include/net/netns/conntrack.h
@@ -109,6 +109,7 @@ struct netns_ct {
- u8 sysctl_auto_assign_helper;
- u8 sysctl_tstamp;
- u8 sysctl_checksum;
-+ u8 sysctl_no_window_check;
-
- struct ct_pcpu __percpu *pcpu_lists;
- struct ip_conntrack_stat __percpu *stat;
+ unsigned int timeouts[TCP_CONNTRACK_TIMEOUT_MAX];
+ u8 tcp_loose;
+ u8 tcp_be_liberal;
++ u8 tcp_no_window_check;
+ u8 tcp_max_retrans;
+ u8 tcp_ignore_invalid_rst;
+ #if IS_ENABLED(CONFIG_NF_FLOW_TABLE)
The current reworked version cause kernel panic when the value is changes and an interface is up. Following the tcp_be_liberal impelementation, reimplement this to permit a safe change of this value without any panic. This has been tested with a QSDK package where tcp_no_window_check is used. Fixes: 92fb51bc9881 ("generic: 5.15: standardize tcp_no_window_check pending patch") Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@gmail.com> --- ...-netfilter_optional_tcp_window_check.patch | 82 ++++++++++--------- 1 file changed, 43 insertions(+), 39 deletions(-)