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authorLinus Torvalds <torvalds@linux-foundation.org>2019-04-24 16:18:59 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-04-24 16:18:59 -0700
commitcd8dead0c39457e58ec1d36db93aedca811d48f1 (patch)
tree6d3e01f3de3afa104f86f4d29206623e5b448d40 /net/netfilter/nf_conntrack_proto_icmp.c
parent11bfe6473bf2c83e4cc44fe97d95a8b0dae1e419 (diff)
parent20ff83f10f113c88d0bb74589389b05250994c16 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller: "Just the usual assortment of small'ish fixes: 1) Conntrack timeout is sometimes not initialized properly, from Alexander Potapenko. 2) Add a reasonable range limit to tcp_min_rtt_wlen to avoid undefined behavior. From ZhangXiaoxu. 3) des1 field of descriptor in stmmac driver is initialized with the wrong variable. From Yue Haibing. 4) Increase mlxsw pci sw reset timeout a little bit more, from Ido Schimmel. 5) Match IOT2000 stmmac devices more accurately, from Su Bao Cheng. 6) Fallback refcount fix in TLS code, from Jakub Kicinski. 7) Fix max MTU check when using XDP in mlx5, from Maxim Mikityanskiy. 8) Fix recursive locking in team driver, from Hangbin Liu. 9) Fix tls_set_device_offload_Rx() deadlock, from Jakub Kicinski. 10) Don't use napi_alloc_frag() outside of softiq context of socionext driver, from Ilias Apalodimas. 11) MAC address increment overflow in ncsi, from Tao Ren. 12) Fix a regression in 8K/1M pool switching of RDS, from Zhu Yanjun. 13) ipv4_link_failure has to validate the headers that are actually there because RAW sockets can pass in arbitrary garbage, from Eric Dumazet" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits) ipv4: add sanity checks in ipv4_link_failure() net/rose: fix unbound loop in rose_loopback_timer() rxrpc: fix race condition in rxrpc_input_packet() net: rds: exchange of 8K and 1M pool net: vrf: Fix operation not supported when set vrf mac net/ncsi: handle overflow when incrementing mac address net: socionext: replace napi_alloc_frag with the netdev variant on init net: atheros: fix spelling mistake "underun" -> "underrun" spi: ST ST95HF NFC: declare missing of table spi: Micrel eth switch: declare missing of table net: stmmac: move stmmac_check_ether_addr() to driver probe netfilter: fix nf_l4proto_log_invalid to log invalid packets netfilter: never get/set skb->tstamp netfilter: ebtables: CONFIG_COMPAT: drop a bogus WARN_ON Documentation: decnet: remove reference to CONFIG_DECNET_ROUTE_FWMARK dt-bindings: add an explanation for internal phy-mode net/tls: don't leak IV and record seq when offload fails net/tls: avoid potential deadlock in tls_set_device_offload_rx() selftests/net: correct the return value for run_afpackettests team: fix possible recursive locking when add slaves ...
Diffstat (limited to 'net/netfilter/nf_conntrack_proto_icmp.c')
-rw-r--r--net/netfilter/nf_conntrack_proto_icmp.c93
1 files changed, 72 insertions, 21 deletions
diff --git a/net/netfilter/nf_conntrack_proto_icmp.c b/net/netfilter/nf_conntrack_proto_icmp.c
index 7df477996b16..9becac953587 100644
--- a/net/netfilter/nf_conntrack_proto_icmp.c
+++ b/net/netfilter/nf_conntrack_proto_icmp.c
@@ -103,49 +103,94 @@ int nf_conntrack_icmp_packet(struct nf_conn *ct,
return NF_ACCEPT;
}
-/* Returns conntrack if it dealt with ICMP, and filled in skb fields */
-static int
-icmp_error_message(struct nf_conn *tmpl, struct sk_buff *skb,
- const struct nf_hook_state *state)
+/* Check inner header is related to any of the existing connections */
+int nf_conntrack_inet_error(struct nf_conn *tmpl, struct sk_buff *skb,
+ unsigned int dataoff,
+ const struct nf_hook_state *state,
+ u8 l4proto, union nf_inet_addr *outer_daddr)
{
struct nf_conntrack_tuple innertuple, origtuple;
const struct nf_conntrack_tuple_hash *h;
const struct nf_conntrack_zone *zone;
enum ip_conntrack_info ctinfo;
struct nf_conntrack_zone tmp;
+ union nf_inet_addr *ct_daddr;
+ enum ip_conntrack_dir dir;
+ struct nf_conn *ct;
WARN_ON(skb_nfct(skb));
zone = nf_ct_zone_tmpl(tmpl, skb, &tmp);
/* Are they talking about one of our connections? */
- if (!nf_ct_get_tuplepr(skb,
- skb_network_offset(skb) + ip_hdrlen(skb)
- + sizeof(struct icmphdr),
- PF_INET, state->net, &origtuple)) {
- pr_debug("icmp_error_message: failed to get tuple\n");
+ if (!nf_ct_get_tuplepr(skb, dataoff,
+ state->pf, state->net, &origtuple))
return -NF_ACCEPT;
- }
/* Ordinarily, we'd expect the inverted tupleproto, but it's
been preserved inside the ICMP. */
- if (!nf_ct_invert_tuple(&innertuple, &origtuple)) {
- pr_debug("icmp_error_message: no match\n");
+ if (!nf_ct_invert_tuple(&innertuple, &origtuple))
return -NF_ACCEPT;
- }
-
- ctinfo = IP_CT_RELATED;
h = nf_conntrack_find_get(state->net, zone, &innertuple);
- if (!h) {
- pr_debug("icmp_error_message: no match\n");
+ if (!h)
+ return -NF_ACCEPT;
+
+ /* Consider: A -> T (=This machine) -> B
+ * Conntrack entry will look like this:
+ * Original: A->B
+ * Reply: B->T (SNAT case) OR A
+ *
+ * When this function runs, we got packet that looks like this:
+ * iphdr|icmphdr|inner_iphdr|l4header (tcp, udp, ..).
+ *
+ * Above nf_conntrack_find_get() makes lookup based on inner_hdr,
+ * so we should expect that destination of the found connection
+ * matches outer header destination address.
+ *
+ * In above example, we can consider these two cases:
+ * 1. Error coming in reply direction from B or M (middle box) to
+ * T (SNAT case) or A.
+ * Inner saddr will be B, dst will be T or A.
+ * The found conntrack will be reply tuple (B->T/A).
+ * 2. Error coming in original direction from A or M to B.
+ * Inner saddr will be A, inner daddr will be B.
+ * The found conntrack will be original tuple (A->B).
+ *
+ * In both cases, conntrack[dir].dst == inner.dst.
+ *
+ * A bogus packet could look like this:
+ * Inner: B->T
+ * Outer: B->X (other machine reachable by T).
+ *
+ * In this case, lookup yields connection A->B and will
+ * set packet from B->X as *RELATED*, even though no connection
+ * from X was ever seen.
+ */
+ ct = nf_ct_tuplehash_to_ctrack(h);
+ dir = NF_CT_DIRECTION(h);
+ ct_daddr = &ct->tuplehash[dir].tuple.dst.u3;
+ if (!nf_inet_addr_cmp(outer_daddr, ct_daddr)) {
+ if (state->pf == AF_INET) {
+ nf_l4proto_log_invalid(skb, state->net, state->pf,
+ l4proto,
+ "outer daddr %pI4 != inner %pI4",
+ &outer_daddr->ip, &ct_daddr->ip);
+ } else if (state->pf == AF_INET6) {
+ nf_l4proto_log_invalid(skb, state->net, state->pf,
+ l4proto,
+ "outer daddr %pI6 != inner %pI6",
+ &outer_daddr->ip6, &ct_daddr->ip6);
+ }
+ nf_ct_put(ct);
return -NF_ACCEPT;
}
- if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
+ ctinfo = IP_CT_RELATED;
+ if (dir == IP_CT_DIR_REPLY)
ctinfo += IP_CT_IS_REPLY;
/* Update skb to refer to this connection */
- nf_ct_set(skb, nf_ct_tuplehash_to_ctrack(h), ctinfo);
+ nf_ct_set(skb, ct, ctinfo);
return NF_ACCEPT;
}
@@ -162,11 +207,12 @@ int nf_conntrack_icmpv4_error(struct nf_conn *tmpl,
struct sk_buff *skb, unsigned int dataoff,
const struct nf_hook_state *state)
{
+ union nf_inet_addr outer_daddr;
const struct icmphdr *icmph;
struct icmphdr _ih;
/* Not enough header? */
- icmph = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_ih), &_ih);
+ icmph = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih);
if (icmph == NULL) {
icmp_error_log(skb, state, "short packet");
return -NF_ACCEPT;
@@ -199,7 +245,12 @@ int nf_conntrack_icmpv4_error(struct nf_conn *tmpl,
icmph->type != ICMP_REDIRECT)
return NF_ACCEPT;
- return icmp_error_message(tmpl, skb, state);
+ memset(&outer_daddr, 0, sizeof(outer_daddr));
+ outer_daddr.ip = ip_hdr(skb)->daddr;
+
+ dataoff += sizeof(*icmph);
+ return nf_conntrack_inet_error(tmpl, skb, dataoff, state,
+ IPPROTO_ICMP, &outer_daddr);
}
#if IS_ENABLED(CONFIG_NF_CT_NETLINK)