[3.8.y.z extended stable] Patch "netfilter: push reasm skb through instead of original frag skbs" has been added to staging queue
Kamal Mostafa
kamal at canonical.com
Wed Dec 11 20:09:37 UTC 2013
This is a note to let you know that I have just added a patch titled
netfilter: push reasm skb through instead of original frag skbs
to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree
which can be found at:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue
This patch is scheduled to be released in version 3.8.13.15.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
------
>From 637a18d24a58603b795ffa3ceac67d49827c8558 Mon Sep 17 00:00:00 2001
From: Jiri Pirko <jiri at resnulli.us>
Date: Wed, 6 Nov 2013 17:52:20 +0100
Subject: netfilter: push reasm skb through instead of original frag skbs
[ Upstream commit 6aafeef03b9d9ecf255f3a80ed85ee070260e1ae ]
Pushing original fragments through causes several problems. For example
for matching, frags may not be matched correctly. Take following
example:
<example>
On HOSTA do:
ip6tables -I INPUT -p icmpv6 -j DROP
ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT
and on HOSTB you do:
ping6 HOSTA -s2000 (MTU is 1500)
Incoming echo requests will be filtered out on HOSTA. This issue does
not occur with smaller packets than MTU (where fragmentation does not happen)
</example>
As was discussed previously, the only correct solution seems to be to use
reassembled skb instead of separete frags. Doing this has positive side
effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams
dances in ipvs and conntrack can be removed.
Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c
entirely and use code in net/ipv6/reassembly.c instead.
Signed-off-by: Jiri Pirko <jiri at resnulli.us>
Acked-by: Julian Anastasov <ja at ssi.bg>
Signed-off-by: Marcelo Ricardo Leitner <mleitner at redhat.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
include/linux/skbuff.h | 32 ---------------
include/net/ip_vs.h | 32 +--------------
include/net/netfilter/ipv6/nf_defrag_ipv6.h | 5 +--
net/core/skbuff.c | 3 --
net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c | 2 +-
net/ipv6/netfilter/nf_conntrack_reasm.c | 19 +--------
net/ipv6/netfilter/nf_defrag_ipv6_hooks.c | 7 +++-
net/netfilter/ipvs/ip_vs_core.c | 55 +-------------------------
net/netfilter/ipvs/ip_vs_pe_sip.c | 8 +---
9 files changed, 12 insertions(+), 151 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index db29f78..ffe740d 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -319,11 +319,6 @@ typedef unsigned int sk_buff_data_t;
typedef unsigned char *sk_buff_data_t;
#endif
-#if defined(CONFIG_NF_DEFRAG_IPV4) || defined(CONFIG_NF_DEFRAG_IPV4_MODULE) || \
- defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE)
-#define NET_SKBUFF_NF_DEFRAG_NEEDED 1
-#endif
-
/**
* struct sk_buff - socket buffer
* @next: Next buffer in list
@@ -356,7 +351,6 @@ typedef unsigned char *sk_buff_data_t;
* @protocol: Packet protocol from driver
* @destructor: Destruct function
* @nfct: Associated connection, if any
- * @nfct_reasm: netfilter conntrack re-assembly pointer
* @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
* @skb_iif: ifindex of device we arrived on
* @tc_index: Traffic control index
@@ -441,9 +435,6 @@ struct sk_buff {
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
struct nf_conntrack *nfct;
#endif
-#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
- struct sk_buff *nfct_reasm;
-#endif
#ifdef CONFIG_BRIDGE_NETFILTER
struct nf_bridge_info *nf_bridge;
#endif
@@ -2572,18 +2563,6 @@ static inline void nf_conntrack_get(struct nf_conntrack *nfct)
atomic_inc(&nfct->use);
}
#endif
-#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
-static inline void nf_conntrack_get_reasm(struct sk_buff *skb)
-{
- if (skb)
- atomic_inc(&skb->users);
-}
-static inline void nf_conntrack_put_reasm(struct sk_buff *skb)
-{
- if (skb)
- kfree_skb(skb);
-}
-#endif
#ifdef CONFIG_BRIDGE_NETFILTER
static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge)
{
@@ -2602,10 +2581,6 @@ static inline void nf_reset(struct sk_buff *skb)
nf_conntrack_put(skb->nfct);
skb->nfct = NULL;
#endif
-#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
- nf_conntrack_put_reasm(skb->nfct_reasm);
- skb->nfct_reasm = NULL;
-#endif
#ifdef CONFIG_BRIDGE_NETFILTER
nf_bridge_put(skb->nf_bridge);
skb->nf_bridge = NULL;
@@ -2627,10 +2602,6 @@ static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
nf_conntrack_get(src->nfct);
dst->nfctinfo = src->nfctinfo;
#endif
-#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
- dst->nfct_reasm = src->nfct_reasm;
- nf_conntrack_get_reasm(src->nfct_reasm);
-#endif
#ifdef CONFIG_BRIDGE_NETFILTER
dst->nf_bridge = src->nf_bridge;
nf_bridge_get(src->nf_bridge);
@@ -2642,9 +2613,6 @@ static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
nf_conntrack_put(dst->nfct);
#endif
-#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
- nf_conntrack_put_reasm(dst->nfct_reasm);
-#endif
#ifdef CONFIG_BRIDGE_NETFILTER
nf_bridge_put(dst->nf_bridge);
#endif
diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index fce8e6b..c358446 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -109,7 +109,6 @@ extern int ip_vs_conn_tab_size;
struct ip_vs_iphdr {
__u32 len; /* IPv4 simply where L4 starts
IPv6 where L4 Transport Header starts */
- __u32 thoff_reasm; /* Transport Header Offset in nfct_reasm skb */
__u16 fragoffs; /* IPv6 fragment offset, 0 if first frag (or not frag)*/
__s16 protocol;
__s32 flags;
@@ -117,34 +116,12 @@ struct ip_vs_iphdr {
union nf_inet_addr daddr;
};
-/* Dependency to module: nf_defrag_ipv6 */
-#if defined(CONFIG_NF_DEFRAG_IPV6) || defined(CONFIG_NF_DEFRAG_IPV6_MODULE)
-static inline struct sk_buff *skb_nfct_reasm(const struct sk_buff *skb)
-{
- return skb->nfct_reasm;
-}
-static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
- int len, void *buffer,
- const struct ip_vs_iphdr *ipvsh)
-{
- if (unlikely(ipvsh->fragoffs && skb_nfct_reasm(skb)))
- return skb_header_pointer(skb_nfct_reasm(skb),
- ipvsh->thoff_reasm, len, buffer);
-
- return skb_header_pointer(skb, offset, len, buffer);
-}
-#else
-static inline struct sk_buff *skb_nfct_reasm(const struct sk_buff *skb)
-{
- return NULL;
-}
static inline void *frag_safe_skb_hp(const struct sk_buff *skb, int offset,
int len, void *buffer,
const struct ip_vs_iphdr *ipvsh)
{
return skb_header_pointer(skb, offset, len, buffer);
}
-#endif
static inline void
ip_vs_fill_ip4hdr(const void *nh, struct ip_vs_iphdr *iphdr)
@@ -171,19 +148,12 @@ ip_vs_fill_iph_skb(int af, const struct sk_buff *skb, struct ip_vs_iphdr *iphdr)
(struct ipv6hdr *)skb_network_header(skb);
iphdr->saddr.in6 = iph->saddr;
iphdr->daddr.in6 = iph->daddr;
- /* ipv6_find_hdr() updates len, flags, thoff_reasm */
- iphdr->thoff_reasm = 0;
+ /* ipv6_find_hdr() updates len, flags */
iphdr->len = 0;
iphdr->flags = 0;
iphdr->protocol = ipv6_find_hdr(skb, &iphdr->len, -1,
&iphdr->fragoffs,
&iphdr->flags);
- /* get proto from re-assembled packet and it's offset */
- if (skb_nfct_reasm(skb))
- iphdr->protocol = ipv6_find_hdr(skb_nfct_reasm(skb),
- &iphdr->thoff_reasm,
- -1, NULL, NULL);
-
} else
#endif
{
diff --git a/include/net/netfilter/ipv6/nf_defrag_ipv6.h b/include/net/netfilter/ipv6/nf_defrag_ipv6.h
index fd79c9a..17920d8 100644
--- a/include/net/netfilter/ipv6/nf_defrag_ipv6.h
+++ b/include/net/netfilter/ipv6/nf_defrag_ipv6.h
@@ -6,10 +6,7 @@ extern void nf_defrag_ipv6_enable(void);
extern int nf_ct_frag6_init(void);
extern void nf_ct_frag6_cleanup(void);
extern struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user);
-extern void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
- struct net_device *in,
- struct net_device *out,
- int (*okfn)(struct sk_buff *));
+extern void nf_ct_frag6_consume_orig(struct sk_buff *skb);
struct inet_frags_ctl;
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 32443eb..21a89b0 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -576,9 +576,6 @@ static void skb_release_head_state(struct sk_buff *skb)
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
nf_conntrack_put(skb->nfct);
#endif
-#ifdef NET_SKBUFF_NF_DEFRAG_NEEDED
- nf_conntrack_put_reasm(skb->nfct_reasm);
-#endif
#ifdef CONFIG_BRIDGE_NETFILTER
nf_bridge_put(skb->nf_bridge);
#endif
diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index 137e245..db57221 100644
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -248,7 +248,7 @@ static unsigned int ipv6_conntrack_local(unsigned int hooknum,
net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
return NF_ACCEPT;
}
- return __ipv6_conntrack_in(dev_net(out), hooknum, skb, in, out, okfn);
+ return nf_conntrack_in(dev_net(out), PF_INET6, hooknum, skb);
}
static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index d05b6ee..7e9cc1b 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -604,31 +604,16 @@ ret_orig:
return skb;
}
-void nf_ct_frag6_output(unsigned int hooknum, struct sk_buff *skb,
- struct net_device *in, struct net_device *out,
- int (*okfn)(struct sk_buff *))
+void nf_ct_frag6_consume_orig(struct sk_buff *skb)
{
struct sk_buff *s, *s2;
- unsigned int ret = 0;
for (s = NFCT_FRAG6_CB(skb)->orig; s;) {
- nf_conntrack_put_reasm(s->nfct_reasm);
- nf_conntrack_get_reasm(skb);
- s->nfct_reasm = skb;
-
s2 = s->next;
s->next = NULL;
-
- if (ret != -ECANCELED)
- ret = NF_HOOK_THRESH(NFPROTO_IPV6, hooknum, s,
- in, out, okfn,
- NF_IP6_PRI_CONNTRACK_DEFRAG + 1);
- else
- kfree_skb(s);
-
+ consume_skb(s);
s = s2;
}
- nf_conntrack_put_reasm(skb);
}
static int nf_ct_net_init(struct net *net)
diff --git a/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c b/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c
index aacd121..581dd9e 100644
--- a/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c
+++ b/net/ipv6/netfilter/nf_defrag_ipv6_hooks.c
@@ -75,8 +75,11 @@ static unsigned int ipv6_defrag(unsigned int hooknum,
if (reasm == skb)
return NF_ACCEPT;
- nf_ct_frag6_output(hooknum, reasm, (struct net_device *)in,
- (struct net_device *)out, okfn);
+ nf_ct_frag6_consume_orig(reasm);
+
+ NF_HOOK_THRESH(NFPROTO_IPV6, hooknum, reasm,
+ (struct net_device *) in, (struct net_device *) out,
+ okfn, NF_IP6_PRI_CONNTRACK_DEFRAG + 1);
return NF_STOLEN;
}
diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index bbbb9a1..c0e060f 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -1132,12 +1132,6 @@ ip_vs_out(unsigned int hooknum, struct sk_buff *skb, int af)
ip_vs_fill_iph_skb(af, skb, &iph);
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
- if (!iph.fragoffs && skb_nfct_reasm(skb)) {
- struct sk_buff *reasm = skb_nfct_reasm(skb);
- /* Save fw mark for coming frags */
- reasm->ipvs_property = 1;
- reasm->mark = skb->mark;
- }
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related;
int verdict = ip_vs_out_icmp_v6(skb, &related,
@@ -1622,12 +1616,6 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
#ifdef CONFIG_IP_VS_IPV6
if (af == AF_INET6) {
- if (!iph.fragoffs && skb_nfct_reasm(skb)) {
- struct sk_buff *reasm = skb_nfct_reasm(skb);
- /* Save fw mark for coming frags. */
- reasm->ipvs_property = 1;
- reasm->mark = skb->mark;
- }
if (unlikely(iph.protocol == IPPROTO_ICMPV6)) {
int related;
int verdict = ip_vs_in_icmp_v6(skb, &related, hooknum,
@@ -1679,9 +1667,8 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
/* sorry, all this trouble for a no-hit :) */
IP_VS_DBG_PKT(12, af, pp, skb, 0,
"ip_vs_in: packet continues traversal as normal");
- if (iph.fragoffs && !skb_nfct_reasm(skb)) {
+ if (iph.fragoffs) {
/* Fragment that couldn't be mapped to a conn entry
- * and don't have any pointer to a reasm skb
* is missing module nf_defrag_ipv6
*/
IP_VS_DBG_RL("Unhandled frag, load nf_defrag_ipv6\n");
@@ -1770,38 +1757,6 @@ ip_vs_local_request4(unsigned int hooknum, struct sk_buff *skb,
#ifdef CONFIG_IP_VS_IPV6
/*
- * AF_INET6 fragment handling
- * Copy info from first fragment, to the rest of them.
- */
-static unsigned int
-ip_vs_preroute_frag6(unsigned int hooknum, struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int (*okfn)(struct sk_buff *))
-{
- struct sk_buff *reasm = skb_nfct_reasm(skb);
- struct net *net;
-
- /* Skip if not a "replay" from nf_ct_frag6_output or first fragment.
- * ipvs_property is set when checking first fragment
- * in ip_vs_in() and ip_vs_out().
- */
- if (reasm)
- IP_VS_DBG(2, "Fragment recv prop:%d\n", reasm->ipvs_property);
- if (!reasm || !reasm->ipvs_property)
- return NF_ACCEPT;
-
- net = skb_net(skb);
- if (!net_ipvs(net)->enable)
- return NF_ACCEPT;
-
- /* Copy stored fw mark, saved in ip_vs_{in,out} */
- skb->mark = reasm->mark;
-
- return NF_ACCEPT;
-}
-
-/*
* AF_INET6 handler in NF_INET_LOCAL_IN chain
* Schedule and forward packets from remote clients
*/
@@ -1944,14 +1899,6 @@ static struct nf_hook_ops ip_vs_ops[] __read_mostly = {
.priority = 100,
},
#ifdef CONFIG_IP_VS_IPV6
- /* After mangle & nat fetch 2:nd fragment and following */
- {
- .hook = ip_vs_preroute_frag6,
- .owner = THIS_MODULE,
- .pf = NFPROTO_IPV6,
- .hooknum = NF_INET_PRE_ROUTING,
- .priority = NF_IP6_PRI_NAT_DST + 1,
- },
/* After packet filtering, change source only for VS/NAT */
{
.hook = ip_vs_reply6,
diff --git a/net/netfilter/ipvs/ip_vs_pe_sip.c b/net/netfilter/ipvs/ip_vs_pe_sip.c
index e5920fb..f4cc87f 100644
--- a/net/netfilter/ipvs/ip_vs_pe_sip.c
+++ b/net/netfilter/ipvs/ip_vs_pe_sip.c
@@ -64,7 +64,6 @@ static int get_callid(const char *dptr, unsigned int dataoff,
static int
ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
{
- struct sk_buff *reasm = skb_nfct_reasm(skb);
struct ip_vs_iphdr iph;
unsigned int dataoff, datalen, matchoff, matchlen;
const char *dptr;
@@ -78,15 +77,10 @@ ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
/* todo: IPv6 fragments:
* I think this only should be done for the first fragment. /HS
*/
- if (reasm) {
- skb = reasm;
- dataoff = iph.thoff_reasm + sizeof(struct udphdr);
- } else
- dataoff = iph.len + sizeof(struct udphdr);
+ dataoff = iph.len + sizeof(struct udphdr);
if (dataoff >= skb->len)
return -EINVAL;
- /* todo: Check if this will mess-up the reasm skb !!! /HS */
retc = skb_linearize(skb);
if (retc < 0)
return retc;
--
1.8.3.2
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