From 8f14c99c7edaaba9c0bb1727d44db6ebf157cc61 Mon Sep 17 00:00:00 2001 From: Tonghao Zhang Date: Sun, 7 Apr 2019 08:14:20 -0700 Subject: [PATCH] netfilter: conntrack: limit sysctl setting for boolean options We use the zero and one to limit the boolean options setting. After this patch we only set 0 or 1 to boolean options for nf conntrack sysctl. Signed-off-by: Tonghao Zhang Signed-off-by: Pablo Neira Ayuso --- include/net/netns/conntrack.h | 6 ++-- net/netfilter/nf_conntrack_standalone.c | 48 +++++++++++++++++-------- 2 files changed, 36 insertions(+), 18 deletions(-) diff --git a/include/net/netns/conntrack.h b/include/net/netns/conntrack.h index f19b53130bf7..806454e767bf 100644 --- a/include/net/netns/conntrack.h +++ b/include/net/netns/conntrack.h @@ -24,9 +24,9 @@ struct nf_generic_net { struct nf_tcp_net { unsigned int timeouts[TCP_CONNTRACK_TIMEOUT_MAX]; - unsigned int tcp_loose; - unsigned int tcp_be_liberal; - unsigned int tcp_max_retrans; + int tcp_loose; + int tcp_be_liberal; + int tcp_max_retrans; }; enum udp_conntrack { diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c index c2ae14c720b4..e0d392cb3075 100644 --- a/net/netfilter/nf_conntrack_standalone.c +++ b/net/netfilter/nf_conntrack_standalone.c @@ -511,6 +511,8 @@ static void nf_conntrack_standalone_fini_proc(struct net *net) /* Log invalid packets of a given protocol */ static int log_invalid_proto_min __read_mostly; static int log_invalid_proto_max __read_mostly = 255; +static int zero; +static int one = 1; /* size the user *wants to set */ static unsigned int nf_conntrack_htable_size_user __read_mostly; @@ -624,9 +626,11 @@ static struct ctl_table nf_ct_sysctl_table[] = { [NF_SYSCTL_CT_CHECKSUM] = { .procname = "nf_conntrack_checksum", .data = &init_net.ct.sysctl_checksum, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, [NF_SYSCTL_CT_LOG_INVALID] = { .procname = "nf_conntrack_log_invalid", @@ -647,33 +651,41 @@ static struct ctl_table nf_ct_sysctl_table[] = { [NF_SYSCTL_CT_ACCT] = { .procname = "nf_conntrack_acct", .data = &init_net.ct.sysctl_acct, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, [NF_SYSCTL_CT_HELPER] = { .procname = "nf_conntrack_helper", .data = &init_net.ct.sysctl_auto_assign_helper, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, #ifdef CONFIG_NF_CONNTRACK_EVENTS [NF_SYSCTL_CT_EVENTS] = { .procname = "nf_conntrack_events", .data = &init_net.ct.sysctl_events, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, #endif #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP [NF_SYSCTL_CT_TIMESTAMP] = { .procname = "nf_conntrack_timestamp", .data = &init_net.ct.sysctl_tstamp, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, #endif [NF_SYSCTL_CT_PROTO_TIMEOUT_GENERIC] = { @@ -744,15 +756,19 @@ static struct ctl_table nf_ct_sysctl_table[] = { }, [NF_SYSCTL_CT_PROTO_TCP_LOOSE] = { .procname = "nf_conntrack_tcp_loose", - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, [NF_SYSCTL_CT_PROTO_TCP_LIBERAL] = { .procname = "nf_conntrack_tcp_be_liberal", - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, [NF_SYSCTL_CT_PROTO_TCP_MAX_RETRANS] = { .procname = "nf_conntrack_tcp_max_retrans", @@ -887,7 +903,9 @@ static struct ctl_table nf_ct_sysctl_table[] = { .procname = "nf_conntrack_dccp_loose", .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, }, #endif #ifdef CONFIG_NF_CT_PROTO_GRE -- 2.30.2