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Diffstat (limited to 'net/ipv6/reassembly.c')
-rw-r--r--net/ipv6/reassembly.c87
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);