diff options
Diffstat (limited to 'net/ipv6/reassembly.c')
| -rw-r--r-- | net/ipv6/reassembly.c | 87 |
1 files changed, 56 insertions, 31 deletions
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 1f5d4d196dcc..25ec8001898d 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -42,6 +42,8 @@ #include <linux/skbuff.h> #include <linux/slab.h> #include <linux/export.h> +#include <linux/tcp.h> +#include <linux/udp.h> #include <net/sock.h> #include <net/snmp.h> @@ -66,11 +68,12 @@ static u8 ip6_frag_ecn(const struct ipv6hdr *ipv6h) static struct inet_frags ip6_frags; static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *skb, - struct sk_buff *prev_tail, struct net_device *dev); + struct sk_buff *prev_tail, struct net_device *dev, + int *refs); static void ip6_frag_expire(struct timer_list *t) { - struct inet_frag_queue *frag = from_timer(frag, t, timer); + struct inet_frag_queue *frag = timer_container_of(frag, t, timer); struct frag_queue *fq; fq = container_of(frag, struct frag_queue, q); @@ -101,19 +104,23 @@ fq_find(struct net *net, __be32 id, const struct ipv6hdr *hdr, int iif) return container_of(q, struct frag_queue, q); } -static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, +static int ip6_frag_queue(struct net *net, + struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff, - u32 *prob_offset) + u32 *prob_offset, int *refs) { - struct net *net = dev_net(skb_dst(skb)->dev); int offset, end, fragsize; struct sk_buff *prev_tail; struct net_device *dev; int err = -ENOENT; + SKB_DR(reason); u8 ecn; - if (fq->q.flags & INET_FRAG_COMPLETE) + /* If reassembly is already done, @skb must be a duplicate frag. */ + if (fq->q.flags & INET_FRAG_COMPLETE) { + SKB_DR_SET(reason, DUP_FRAG); goto err; + } err = -EINVAL; offset = ntohs(fhdr->frag_off) & ~0x7; @@ -192,6 +199,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, fq->iif = dev->ifindex; fq->q.stamp = skb->tstamp; + fq->q.tstamp_type = skb->tstamp_type; fq->q.meat += skb->len; fq->ecn |= ecn; add_frag_mem_limit(fq->q.fqdir, skb->truesize); @@ -213,7 +221,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, unsigned long orefdst = skb->_skb_refdst; skb->_skb_refdst = 0UL; - err = ip6_frag_reasm(fq, skb, prev_tail, dev); + err = ip6_frag_reasm(fq, skb, prev_tail, dev, refs); skb->_skb_refdst = orefdst; return err; } @@ -223,18 +231,19 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, insert_error: if (err == IPFRAG_DUP) { - kfree_skb(skb); - return -EINVAL; + SKB_DR_SET(reason, DUP_FRAG); + err = -EINVAL; + goto err; } err = -EINVAL; __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASM_OVERLAPS); discard_fq: - inet_frag_kill(&fq->q); + inet_frag_kill(&fq->q, refs); __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); err: - kfree_skb(skb); + kfree_skb_reason(skb, reason); return err; } @@ -246,7 +255,8 @@ err: * the last and the first frames arrived and all the bits are here. */ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *skb, - struct sk_buff *prev_tail, struct net_device *dev) + struct sk_buff *prev_tail, struct net_device *dev, + int *refs) { struct net *net = fq->q.fqdir->net; unsigned int nhoff; @@ -254,7 +264,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *skb, int payload_len; u8 ecn; - inet_frag_kill(&fq->q); + inet_frag_kill(&fq->q, refs); ecn = ip_frag_ecn_table[fq->ecn]; if (unlikely(ecn == 0xff)) @@ -264,9 +274,9 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *skb, if (!reasm_data) goto out_oom; - payload_len = ((skb->data - skb_network_header(skb)) - + payload_len = -skb_network_offset(skb) - sizeof(struct ipv6hdr) + fq->q.len - - sizeof(struct frag_hdr)); + sizeof(struct frag_hdr); if (payload_len > IPV6_MAXPLEN) goto out_oversize; @@ -295,9 +305,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *skb, skb_postpush_rcsum(skb, skb_network_header(skb), skb_network_header_len(skb)); - rcu_read_lock(); __IP6_INC_STATS(net, __in6_dev_stats_get(dev, skb), IPSTATS_MIB_REASMOKS); - rcu_read_unlock(); fq->q.rb_fragments = RB_ROOT; fq->q.fragments_tail = NULL; fq->q.last_run_head = NULL; @@ -309,19 +317,18 @@ out_oversize: out_oom: net_dbg_ratelimited("ip6_frag_reasm: no memory for reassembly\n"); out_fail: - rcu_read_lock(); __IP6_INC_STATS(net, __in6_dev_stats_get(dev, skb), IPSTATS_MIB_REASMFAILS); - rcu_read_unlock(); - inet_frag_kill(&fq->q); + inet_frag_kill(&fq->q, refs); return -1; } static int ipv6_frag_rcv(struct sk_buff *skb) { + const struct ipv6hdr *hdr = ipv6_hdr(skb); + struct net *net = skb_dst_dev_net(skb); struct frag_hdr *fhdr; struct frag_queue *fq; - const struct ipv6hdr *hdr = ipv6_hdr(skb); - struct net *net = dev_net(skb_dst(skb)->dev); + u8 nexthdr; int iif; if (IP6CB(skb)->flags & IP6SKB_FRAGMENTED) @@ -340,7 +347,7 @@ static int ipv6_frag_rcv(struct sk_buff *skb) hdr = ipv6_hdr(skb); fhdr = (struct frag_hdr *)skb_transport_header(skb); - if (!(fhdr->frag_off & htons(0xFFF9))) { + if (!(fhdr->frag_off & htons(IP6_OFFSET | IP6_MF))) { /* It is not a fragmented frame */ skb->transport_header += sizeof(struct frag_hdr); __IP6_INC_STATS(net, @@ -348,23 +355,41 @@ static int ipv6_frag_rcv(struct sk_buff *skb) IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb); IP6CB(skb)->flags |= IP6SKB_FRAGMENTED; + IP6CB(skb)->frag_max_size = ntohs(hdr->payload_len) + + sizeof(struct ipv6hdr); return 1; } + /* RFC 8200, Section 4.5 Fragment Header: + * If the first fragment does not include all headers through an + * Upper-Layer header, then that fragment should be discarded and + * an ICMP Parameter Problem, Code 3, message should be sent to + * the source of the fragment, with the Pointer field set to zero. + */ + nexthdr = hdr->nexthdr; + if (ipv6frag_thdr_truncated(skb, skb_network_offset(skb) + sizeof(struct ipv6hdr), &nexthdr)) { + __IP6_INC_STATS(net, __in6_dev_get_safely(skb->dev), + IPSTATS_MIB_INHDRERRORS); + icmpv6_param_prob(skb, ICMPV6_HDR_INCOMP, 0); + return -1; + } + iif = skb->dev ? skb->dev->ifindex : 0; + rcu_read_lock(); fq = fq_find(net, fhdr->identification, hdr, iif); if (fq) { u32 prob_offset = 0; - int ret; + int ret, refs = 0; spin_lock(&fq->q.lock); fq->iif = iif; - ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff, - &prob_offset); + ret = ip6_frag_queue(net, fq, skb, fhdr, IP6CB(skb)->nhoff, + &prob_offset, &refs); spin_unlock(&fq->q.lock); - inet_frag_put(&fq->q); + rcu_read_unlock(); + inet_frag_putn(&fq->q, refs); if (prob_offset) { __IP6_INC_STATS(net, __in6_dev_get_safely(skb->dev), IPSTATS_MIB_INHDRERRORS); @@ -373,6 +398,7 @@ static int ipv6_frag_rcv(struct sk_buff *skb) } return ret; } + rcu_read_unlock(); __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); kfree_skb(skb); @@ -411,7 +437,6 @@ static struct ctl_table ip6_frags_ns_ctl_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, - { } }; /* secret interval has been deprecated */ @@ -424,7 +449,6 @@ static struct ctl_table ip6_frags_ctl_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, - { } }; static int __net_init ip6_frags_ns_sysctl_register(struct net *net) @@ -445,7 +469,8 @@ static int __net_init ip6_frags_ns_sysctl_register(struct net *net) table[1].extra2 = &net->ipv6.fqdir->high_thresh; table[2].data = &net->ipv6.fqdir->timeout; - hdr = register_net_sysctl(net, "net/ipv6", table); + hdr = register_net_sysctl_sz(net, "net/ipv6", table, + ARRAY_SIZE(ip6_frags_ns_ctl_table)); if (!hdr) goto err_reg; @@ -461,7 +486,7 @@ err_alloc: static void __net_exit ip6_frags_ns_sysctl_unregister(struct net *net) { - struct ctl_table *table; + const struct ctl_table *table; table = net->ipv6.sysctl.frags_hdr->ctl_table_arg; unregister_net_sysctl_table(net->ipv6.sysctl.frags_hdr); |
