From c392c159605956c7bd4a264ab4490e2b2704c0cd Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 13 Jun 2014 12:53:17 +0200 Subject: conntrackd: build: fix crash when optional kernel modules are not loaded Fix a possible crash if conntrackd sees DCCP, SCTP and ICMPv6 traffic and the corresponding kernel modules that track this traffic are not available. Fixes: http://bugzilla.netfilter.org/show_bug.cgi?id=910 Signed-off-by: Pablo Neira Ayuso --- src/build.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) (limited to 'src/build.c') diff --git a/src/build.c b/src/build.c index 5799b51..9ba8b57 100644 --- a/src/build.c +++ b/src/build.c @@ -105,14 +105,14 @@ static enum nf_conntrack_attr nat_type[] = ATTR_ORIG_NAT_SEQ_OFFSET_AFTER, ATTR_REPL_NAT_SEQ_CORRECTION_POS, ATTR_REPL_NAT_SEQ_OFFSET_BEFORE, ATTR_REPL_NAT_SEQ_OFFSET_AFTER }; +/* ICMP, UDP and TCP are always loaded with nf_conntrack_ipv4 */ static void build_l4proto_tcp(const struct nf_conntrack *ct, struct nethdr *n) { - ct_build_group(ct, ATTR_GRP_ORIG_PORT, n, NTA_PORT, - sizeof(struct nfct_attr_grp_port)); - if (!nfct_attr_is_set(ct, ATTR_TCP_STATE)) return; + ct_build_group(ct, ATTR_GRP_ORIG_PORT, n, NTA_PORT, + sizeof(struct nfct_attr_grp_port)); ct_build_u8(ct, ATTR_TCP_STATE, n, NTA_TCP_STATE); if (CONFIG(sync).tcp_window_tracking) { ct_build_u8(ct, ATTR_TCP_WSCALE_ORIG, n, NTA_TCP_WSCALE_ORIG); @@ -122,12 +122,12 @@ static void build_l4proto_tcp(const struct nf_conntrack *ct, struct nethdr *n) static void build_l4proto_sctp(const struct nf_conntrack *ct, struct nethdr *n) { - ct_build_group(ct, ATTR_GRP_ORIG_PORT, n, NTA_PORT, - sizeof(struct nfct_attr_grp_port)); - + /* SCTP is optional, make sure nf_conntrack_sctp is loaded */ if (!nfct_attr_is_set(ct, ATTR_SCTP_STATE)) return; + ct_build_group(ct, ATTR_GRP_ORIG_PORT, n, NTA_PORT, + sizeof(struct nfct_attr_grp_port)); ct_build_u8(ct, ATTR_SCTP_STATE, n, NTA_SCTP_STATE); ct_build_u32(ct, ATTR_SCTP_VTAG_ORIG, n, NTA_SCTP_VTAG_ORIG); ct_build_u32(ct, ATTR_SCTP_VTAG_REPL, n, NTA_SCTP_VTAG_REPL); @@ -135,18 +135,22 @@ static void build_l4proto_sctp(const struct nf_conntrack *ct, struct nethdr *n) static void build_l4proto_dccp(const struct nf_conntrack *ct, struct nethdr *n) { - ct_build_group(ct, ATTR_GRP_ORIG_PORT, n, NTA_PORT, - sizeof(struct nfct_attr_grp_port)); - + /* DCCP is optional, make sure nf_conntrack_dccp is loaded */ if (!nfct_attr_is_set(ct, ATTR_DCCP_STATE)) return; + ct_build_group(ct, ATTR_GRP_ORIG_PORT, n, NTA_PORT, + sizeof(struct nfct_attr_grp_port)); ct_build_u8(ct, ATTR_DCCP_STATE, n, NTA_DCCP_STATE); ct_build_u8(ct, ATTR_DCCP_ROLE, n, NTA_DCCP_ROLE); } static void build_l4proto_icmp(const struct nf_conntrack *ct, struct nethdr *n) { + /* This is also used by ICMPv6 and nf_conntrack_ipv6 is optional */ + if (!nfct_attr_is_set(ct, ATTR_ICMP_TYPE)) + return; + ct_build_u8(ct, ATTR_ICMP_TYPE, n, NTA_ICMP_TYPE); ct_build_u8(ct, ATTR_ICMP_CODE, n, NTA_ICMP_CODE); ct_build_u16(ct, ATTR_ICMP_ID, n, NTA_ICMP_ID); -- cgit v1.2.3