From: Christian 'Ansuel' Marangi Date: Sat, 14 May 2022 17:42:24 +0000 (+0200) Subject: generic: 5.15: fix panic on tcp_no_window_check set with interface up X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=03685d347025e62faa8f89d0502dcd1dcf6152b4;p=openwrt%2Fstaging%2Fnbd.git generic: 5.15: fix panic on tcp_no_window_check set with interface up 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 --- diff --git a/target/linux/generic/pending-5.15/613-netfilter_optional_tcp_window_check.patch b/target/linux/generic/pending-5.15/613-netfilter_optional_tcp_window_check.patch index b9919ae475..1ddfc8e014 100644 --- a/target/linux/generic/pending-5.15/613-netfilter_optional_tcp_window_check.patch +++ b/target/linux/generic/pending-5.15/613-netfilter_optional_tcp_window_check.patch @@ -2,6 +2,7 @@ From: Felix Fietkau Subject: netfilter: optional tcp window check Signed-off-by: Felix Fietkau +Signed-off-by: Christian 'Ansuel' Marangi --- net/netfilter/nf_conntrack_proto_tcp.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) @@ -12,68 +13,71 @@ Signed-off-by: Felix Fietkau 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)