ipv6: reassembly: use seperate reassembly queues for conntrack and local delivery

Currently the same reassembly queue might be used for packets reassembled
by conntrack in different positions in the stack (PREROUTING/LOCAL_OUT),
as well as local delivery. This can cause "packet jumps" when the fragment
completing a reassembled packet is queued from a different position in the
stack than the previous ones.

Add a "user" identifier to the reassembly queue key to seperate the queues
of each caller, similar to what we do for IPv4.

Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Patrick McHardy 2009-12-15 16:59:18 +01:00
parent 9abfe315de
commit 0b5ccb2ee2
5 changed files with 27 additions and 7 deletions

View File

@ -350,8 +350,15 @@ static inline int ipv6_prefix_equal(const struct in6_addr *a1,
struct inet_frag_queue;
enum ip6_defrag_users {
IP6_DEFRAG_LOCAL_DELIVER,
IP6_DEFRAG_CONNTRACK_IN,
IP6_DEFRAG_CONNTRACK_OUT,
};
struct ip6_create_arg {
__be32 id;
u32 user;
struct in6_addr *src;
struct in6_addr *dst;
};

View File

@ -9,7 +9,7 @@ extern struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6;
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);
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,

View File

@ -187,6 +187,16 @@ out:
return nf_conntrack_confirm(skb);
}
static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
struct sk_buff *skb)
{
if (hooknum == NF_INET_PRE_ROUTING)
return IP6_DEFRAG_CONNTRACK_IN;
else
return IP6_DEFRAG_CONNTRACK_OUT;
}
static unsigned int ipv6_defrag(unsigned int hooknum,
struct sk_buff *skb,
const struct net_device *in,
@ -199,8 +209,7 @@ static unsigned int ipv6_defrag(unsigned int hooknum,
if (skb->nfct)
return NF_ACCEPT;
reasm = nf_ct_frag6_gather(skb);
reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(hooknum, skb));
/* queued */
if (reasm == NULL)
return NF_STOLEN;

View File

@ -168,13 +168,14 @@ out:
/* Creation primitives. */
static __inline__ struct nf_ct_frag6_queue *
fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst)
fq_find(__be32 id, u32 user, struct in6_addr *src, struct in6_addr *dst)
{
struct inet_frag_queue *q;
struct ip6_create_arg arg;
unsigned int hash;
arg.id = id;
arg.user = user;
arg.src = src;
arg.dst = dst;
@ -559,7 +560,7 @@ find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff)
return 0;
}
struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb)
struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb, u32 user)
{
struct sk_buff *clone;
struct net_device *dev = skb->dev;
@ -605,7 +606,7 @@ struct sk_buff *nf_ct_frag6_gather(struct sk_buff *skb)
if (atomic_read(&nf_init_frags.mem) > nf_init_frags.high_thresh)
nf_ct_frag6_evictor();
fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr);
fq = fq_find(fhdr->identification, user, &hdr->saddr, &hdr->daddr);
if (fq == NULL) {
pr_debug("Can't find and can't create new queue\n");
goto ret_orig;

View File

@ -72,6 +72,7 @@ struct frag_queue
struct inet_frag_queue q;
__be32 id; /* fragment id */
u32 user;
struct in6_addr saddr;
struct in6_addr daddr;
@ -141,7 +142,7 @@ int ip6_frag_match(struct inet_frag_queue *q, void *a)
struct ip6_create_arg *arg = a;
fq = container_of(q, struct frag_queue, q);
return (fq->id == arg->id &&
return (fq->id == arg->id && fq->user == arg->user &&
ipv6_addr_equal(&fq->saddr, arg->src) &&
ipv6_addr_equal(&fq->daddr, arg->dst));
}
@ -163,6 +164,7 @@ void ip6_frag_init(struct inet_frag_queue *q, void *a)
struct ip6_create_arg *arg = a;
fq->id = arg->id;
fq->user = arg->user;
ipv6_addr_copy(&fq->saddr, arg->src);
ipv6_addr_copy(&fq->daddr, arg->dst);
}
@ -243,6 +245,7 @@ fq_find(struct net *net, __be32 id, struct in6_addr *src, struct in6_addr *dst,
unsigned int hash;
arg.id = id;
arg.user = IP6_DEFRAG_LOCAL_DELIVER;
arg.src = src;
arg.dst = dst;