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c899710fe7
Move from register_net_sysctl to register_net_sysctl_sz for all the networking related files. Do this while making sure to mirror the NULL assignments with a table_size of zero for the unprivileged users. We need to move to the new function in preparation for when we change SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do so would erroneously allow ARRAY_SIZE() to be called on a pointer. We hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all the relevant net sysctl registering functions to register_net_sysctl_sz in subsequent commits. An additional size function was added to the following files in order to calculate the size of an array that is defined in another file: include/net/ipv6.h net/ipv6/icmp.c net/ipv6/route.c net/ipv6/sysctl_net_ipv6.c Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
762 lines
18 KiB
C
762 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* INET An implementation of the TCP/IP protocol suite for the LINUX
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* operating system. INET is implemented using the BSD Socket
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* interface as the means of communication with the user level.
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*
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* The IP fragmentation functionality.
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*
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* Authors: Fred N. van Kempen <waltje@uWalt.NL.Mugnet.ORG>
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* Alan Cox <alan@lxorguk.ukuu.org.uk>
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*
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* Fixes:
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* Alan Cox : Split from ip.c , see ip_input.c for history.
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* David S. Miller : Begin massive cleanup...
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* Andi Kleen : Add sysctls.
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* xxxx : Overlapfrag bug.
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* Ultima : ip_expire() kernel panic.
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* Bill Hawes : Frag accounting and evictor fixes.
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* John McDonald : 0 length frag bug.
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* Alexey Kuznetsov: SMP races, threading, cleanup.
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* Patrick McHardy : LRU queue of frag heads for evictor.
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*/
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#define pr_fmt(fmt) "IPv4: " fmt
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#include <linux/compiler.h>
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/mm.h>
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#include <linux/jiffies.h>
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#include <linux/skbuff.h>
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#include <linux/list.h>
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#include <linux/ip.h>
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#include <linux/icmp.h>
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#include <linux/netdevice.h>
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#include <linux/jhash.h>
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#include <linux/random.h>
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#include <linux/slab.h>
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#include <net/route.h>
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#include <net/dst.h>
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#include <net/sock.h>
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#include <net/ip.h>
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#include <net/icmp.h>
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#include <net/checksum.h>
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#include <net/inetpeer.h>
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#include <net/inet_frag.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/inet.h>
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#include <linux/netfilter_ipv4.h>
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#include <net/inet_ecn.h>
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#include <net/l3mdev.h>
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/* NOTE. Logic of IP defragmentation is parallel to corresponding IPv6
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* code now. If you change something here, _PLEASE_ update ipv6/reassembly.c
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* as well. Or notify me, at least. --ANK
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*/
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static const char ip_frag_cache_name[] = "ip4-frags";
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/* Describe an entry in the "incomplete datagrams" queue. */
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struct ipq {
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struct inet_frag_queue q;
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u8 ecn; /* RFC3168 support */
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u16 max_df_size; /* largest frag with DF set seen */
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int iif;
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unsigned int rid;
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struct inet_peer *peer;
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};
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static u8 ip4_frag_ecn(u8 tos)
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{
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return 1 << (tos & INET_ECN_MASK);
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}
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static struct inet_frags ip4_frags;
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static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
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struct sk_buff *prev_tail, struct net_device *dev);
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static void ip4_frag_init(struct inet_frag_queue *q, const void *a)
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{
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struct ipq *qp = container_of(q, struct ipq, q);
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struct net *net = q->fqdir->net;
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const struct frag_v4_compare_key *key = a;
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q->key.v4 = *key;
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qp->ecn = 0;
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qp->peer = q->fqdir->max_dist ?
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inet_getpeer_v4(net->ipv4.peers, key->saddr, key->vif, 1) :
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NULL;
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}
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static void ip4_frag_free(struct inet_frag_queue *q)
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{
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struct ipq *qp;
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qp = container_of(q, struct ipq, q);
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if (qp->peer)
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inet_putpeer(qp->peer);
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}
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/* Destruction primitives. */
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static void ipq_put(struct ipq *ipq)
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{
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inet_frag_put(&ipq->q);
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}
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/* Kill ipq entry. It is not destroyed immediately,
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* because caller (and someone more) holds reference count.
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*/
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static void ipq_kill(struct ipq *ipq)
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{
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inet_frag_kill(&ipq->q);
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}
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static bool frag_expire_skip_icmp(u32 user)
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{
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return user == IP_DEFRAG_AF_PACKET ||
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ip_defrag_user_in_between(user, IP_DEFRAG_CONNTRACK_IN,
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__IP_DEFRAG_CONNTRACK_IN_END) ||
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ip_defrag_user_in_between(user, IP_DEFRAG_CONNTRACK_BRIDGE_IN,
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__IP_DEFRAG_CONNTRACK_BRIDGE_IN);
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}
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/*
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* Oops, a fragment queue timed out. Kill it and send an ICMP reply.
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*/
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static void ip_expire(struct timer_list *t)
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{
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struct inet_frag_queue *frag = from_timer(frag, t, timer);
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const struct iphdr *iph;
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struct sk_buff *head = NULL;
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struct net *net;
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struct ipq *qp;
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int err;
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qp = container_of(frag, struct ipq, q);
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net = qp->q.fqdir->net;
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rcu_read_lock();
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/* Paired with WRITE_ONCE() in fqdir_pre_exit(). */
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if (READ_ONCE(qp->q.fqdir->dead))
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goto out_rcu_unlock;
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spin_lock(&qp->q.lock);
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if (qp->q.flags & INET_FRAG_COMPLETE)
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goto out;
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qp->q.flags |= INET_FRAG_DROP;
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ipq_kill(qp);
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__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
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__IP_INC_STATS(net, IPSTATS_MIB_REASMTIMEOUT);
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if (!(qp->q.flags & INET_FRAG_FIRST_IN))
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goto out;
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/* sk_buff::dev and sk_buff::rbnode are unionized. So we
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* pull the head out of the tree in order to be able to
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* deal with head->dev.
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*/
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head = inet_frag_pull_head(&qp->q);
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if (!head)
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goto out;
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head->dev = dev_get_by_index_rcu(net, qp->iif);
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if (!head->dev)
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goto out;
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/* skb has no dst, perform route lookup again */
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iph = ip_hdr(head);
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err = ip_route_input_noref(head, iph->daddr, iph->saddr,
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iph->tos, head->dev);
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if (err)
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goto out;
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/* Only an end host needs to send an ICMP
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* "Fragment Reassembly Timeout" message, per RFC792.
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*/
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if (frag_expire_skip_icmp(qp->q.key.v4.user) &&
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(skb_rtable(head)->rt_type != RTN_LOCAL))
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goto out;
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spin_unlock(&qp->q.lock);
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icmp_send(head, ICMP_TIME_EXCEEDED, ICMP_EXC_FRAGTIME, 0);
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goto out_rcu_unlock;
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out:
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spin_unlock(&qp->q.lock);
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out_rcu_unlock:
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rcu_read_unlock();
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kfree_skb_reason(head, SKB_DROP_REASON_FRAG_REASM_TIMEOUT);
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ipq_put(qp);
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}
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/* Find the correct entry in the "incomplete datagrams" queue for
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* this IP datagram, and create new one, if nothing is found.
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*/
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static struct ipq *ip_find(struct net *net, struct iphdr *iph,
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u32 user, int vif)
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{
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struct frag_v4_compare_key key = {
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.saddr = iph->saddr,
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.daddr = iph->daddr,
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.user = user,
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.vif = vif,
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.id = iph->id,
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.protocol = iph->protocol,
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};
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struct inet_frag_queue *q;
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q = inet_frag_find(net->ipv4.fqdir, &key);
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if (!q)
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return NULL;
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return container_of(q, struct ipq, q);
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}
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/* Is the fragment too far ahead to be part of ipq? */
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static int ip_frag_too_far(struct ipq *qp)
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{
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struct inet_peer *peer = qp->peer;
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unsigned int max = qp->q.fqdir->max_dist;
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unsigned int start, end;
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int rc;
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if (!peer || !max)
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return 0;
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start = qp->rid;
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end = atomic_inc_return(&peer->rid);
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qp->rid = end;
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rc = qp->q.fragments_tail && (end - start) > max;
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if (rc)
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__IP_INC_STATS(qp->q.fqdir->net, IPSTATS_MIB_REASMFAILS);
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return rc;
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}
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static int ip_frag_reinit(struct ipq *qp)
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{
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unsigned int sum_truesize = 0;
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if (!mod_timer(&qp->q.timer, jiffies + qp->q.fqdir->timeout)) {
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refcount_inc(&qp->q.refcnt);
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return -ETIMEDOUT;
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}
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sum_truesize = inet_frag_rbtree_purge(&qp->q.rb_fragments,
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SKB_DROP_REASON_FRAG_TOO_FAR);
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sub_frag_mem_limit(qp->q.fqdir, sum_truesize);
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qp->q.flags = 0;
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qp->q.len = 0;
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qp->q.meat = 0;
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qp->q.rb_fragments = RB_ROOT;
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qp->q.fragments_tail = NULL;
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qp->q.last_run_head = NULL;
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qp->iif = 0;
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qp->ecn = 0;
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return 0;
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}
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/* Add new segment to existing queue. */
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static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb)
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{
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struct net *net = qp->q.fqdir->net;
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int ihl, end, flags, offset;
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struct sk_buff *prev_tail;
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struct net_device *dev;
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unsigned int fragsize;
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int err = -ENOENT;
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SKB_DR(reason);
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u8 ecn;
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/* If reassembly is already done, @skb must be a duplicate frag. */
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if (qp->q.flags & INET_FRAG_COMPLETE) {
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SKB_DR_SET(reason, DUP_FRAG);
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goto err;
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}
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if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) &&
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unlikely(ip_frag_too_far(qp)) &&
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unlikely(err = ip_frag_reinit(qp))) {
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ipq_kill(qp);
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goto err;
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}
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ecn = ip4_frag_ecn(ip_hdr(skb)->tos);
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offset = ntohs(ip_hdr(skb)->frag_off);
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flags = offset & ~IP_OFFSET;
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offset &= IP_OFFSET;
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offset <<= 3; /* offset is in 8-byte chunks */
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ihl = ip_hdrlen(skb);
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/* Determine the position of this fragment. */
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end = offset + skb->len - skb_network_offset(skb) - ihl;
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err = -EINVAL;
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/* Is this the final fragment? */
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if ((flags & IP_MF) == 0) {
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/* If we already have some bits beyond end
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* or have different end, the segment is corrupted.
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*/
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if (end < qp->q.len ||
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((qp->q.flags & INET_FRAG_LAST_IN) && end != qp->q.len))
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goto discard_qp;
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qp->q.flags |= INET_FRAG_LAST_IN;
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qp->q.len = end;
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} else {
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if (end&7) {
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end &= ~7;
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if (skb->ip_summed != CHECKSUM_UNNECESSARY)
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skb->ip_summed = CHECKSUM_NONE;
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}
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if (end > qp->q.len) {
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/* Some bits beyond end -> corruption. */
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if (qp->q.flags & INET_FRAG_LAST_IN)
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goto discard_qp;
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qp->q.len = end;
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}
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}
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if (end == offset)
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goto discard_qp;
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err = -ENOMEM;
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if (!pskb_pull(skb, skb_network_offset(skb) + ihl))
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goto discard_qp;
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err = pskb_trim_rcsum(skb, end - offset);
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if (err)
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goto discard_qp;
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/* Note : skb->rbnode and skb->dev share the same location. */
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dev = skb->dev;
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/* Makes sure compiler wont do silly aliasing games */
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barrier();
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prev_tail = qp->q.fragments_tail;
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err = inet_frag_queue_insert(&qp->q, skb, offset, end);
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if (err)
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goto insert_error;
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if (dev)
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qp->iif = dev->ifindex;
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qp->q.stamp = skb->tstamp;
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qp->q.mono_delivery_time = skb->mono_delivery_time;
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qp->q.meat += skb->len;
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qp->ecn |= ecn;
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add_frag_mem_limit(qp->q.fqdir, skb->truesize);
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if (offset == 0)
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qp->q.flags |= INET_FRAG_FIRST_IN;
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fragsize = skb->len + ihl;
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if (fragsize > qp->q.max_size)
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qp->q.max_size = fragsize;
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if (ip_hdr(skb)->frag_off & htons(IP_DF) &&
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fragsize > qp->max_df_size)
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qp->max_df_size = fragsize;
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if (qp->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
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qp->q.meat == qp->q.len) {
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unsigned long orefdst = skb->_skb_refdst;
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skb->_skb_refdst = 0UL;
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err = ip_frag_reasm(qp, skb, prev_tail, dev);
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skb->_skb_refdst = orefdst;
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if (err)
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inet_frag_kill(&qp->q);
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return err;
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}
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skb_dst_drop(skb);
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return -EINPROGRESS;
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insert_error:
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if (err == IPFRAG_DUP) {
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SKB_DR_SET(reason, DUP_FRAG);
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err = -EINVAL;
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goto err;
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}
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err = -EINVAL;
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__IP_INC_STATS(net, IPSTATS_MIB_REASM_OVERLAPS);
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discard_qp:
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inet_frag_kill(&qp->q);
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__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
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err:
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kfree_skb_reason(skb, reason);
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return err;
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}
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static bool ip_frag_coalesce_ok(const struct ipq *qp)
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{
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return qp->q.key.v4.user == IP_DEFRAG_LOCAL_DELIVER;
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}
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/* Build a new IP datagram from all its fragments. */
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static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
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struct sk_buff *prev_tail, struct net_device *dev)
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{
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struct net *net = qp->q.fqdir->net;
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struct iphdr *iph;
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void *reasm_data;
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int len, err;
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u8 ecn;
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ipq_kill(qp);
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ecn = ip_frag_ecn_table[qp->ecn];
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if (unlikely(ecn == 0xff)) {
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err = -EINVAL;
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goto out_fail;
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}
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/* Make the one we just received the head. */
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reasm_data = inet_frag_reasm_prepare(&qp->q, skb, prev_tail);
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if (!reasm_data)
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goto out_nomem;
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len = ip_hdrlen(skb) + qp->q.len;
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err = -E2BIG;
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if (len > 65535)
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goto out_oversize;
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inet_frag_reasm_finish(&qp->q, skb, reasm_data,
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ip_frag_coalesce_ok(qp));
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skb->dev = dev;
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IPCB(skb)->frag_max_size = max(qp->max_df_size, qp->q.max_size);
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iph = ip_hdr(skb);
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iph->tot_len = htons(len);
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iph->tos |= ecn;
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/* When we set IP_DF on a refragmented skb we must also force a
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* call to ip_fragment to avoid forwarding a DF-skb of size s while
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* original sender only sent fragments of size f (where f < s).
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*
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* We only set DF/IPSKB_FRAG_PMTU if such DF fragment was the largest
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* frag seen to avoid sending tiny DF-fragments in case skb was built
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* from one very small df-fragment and one large non-df frag.
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*/
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if (qp->max_df_size == qp->q.max_size) {
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IPCB(skb)->flags |= IPSKB_FRAG_PMTU;
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iph->frag_off = htons(IP_DF);
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} else {
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iph->frag_off = 0;
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}
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ip_send_check(iph);
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__IP_INC_STATS(net, IPSTATS_MIB_REASMOKS);
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qp->q.rb_fragments = RB_ROOT;
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qp->q.fragments_tail = NULL;
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qp->q.last_run_head = NULL;
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return 0;
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out_nomem:
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net_dbg_ratelimited("queue_glue: no memory for gluing queue %p\n", qp);
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err = -ENOMEM;
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goto out_fail;
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out_oversize:
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net_info_ratelimited("Oversized IP packet from %pI4\n", &qp->q.key.v4.saddr);
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out_fail:
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__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
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return err;
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}
|
|
|
|
/* Process an incoming IP datagram fragment. */
|
|
int ip_defrag(struct net *net, struct sk_buff *skb, u32 user)
|
|
{
|
|
struct net_device *dev = skb->dev ? : skb_dst(skb)->dev;
|
|
int vif = l3mdev_master_ifindex_rcu(dev);
|
|
struct ipq *qp;
|
|
|
|
__IP_INC_STATS(net, IPSTATS_MIB_REASMREQDS);
|
|
skb_orphan(skb);
|
|
|
|
/* Lookup (or create) queue header */
|
|
qp = ip_find(net, ip_hdr(skb), user, vif);
|
|
if (qp) {
|
|
int ret;
|
|
|
|
spin_lock(&qp->q.lock);
|
|
|
|
ret = ip_frag_queue(qp, skb);
|
|
|
|
spin_unlock(&qp->q.lock);
|
|
ipq_put(qp);
|
|
return ret;
|
|
}
|
|
|
|
__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);
|
|
kfree_skb(skb);
|
|
return -ENOMEM;
|
|
}
|
|
EXPORT_SYMBOL(ip_defrag);
|
|
|
|
struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user)
|
|
{
|
|
struct iphdr iph;
|
|
int netoff;
|
|
u32 len;
|
|
|
|
if (skb->protocol != htons(ETH_P_IP))
|
|
return skb;
|
|
|
|
netoff = skb_network_offset(skb);
|
|
|
|
if (skb_copy_bits(skb, netoff, &iph, sizeof(iph)) < 0)
|
|
return skb;
|
|
|
|
if (iph.ihl < 5 || iph.version != 4)
|
|
return skb;
|
|
|
|
len = ntohs(iph.tot_len);
|
|
if (skb->len < netoff + len || len < (iph.ihl * 4))
|
|
return skb;
|
|
|
|
if (ip_is_fragment(&iph)) {
|
|
skb = skb_share_check(skb, GFP_ATOMIC);
|
|
if (skb) {
|
|
if (!pskb_may_pull(skb, netoff + iph.ihl * 4)) {
|
|
kfree_skb(skb);
|
|
return NULL;
|
|
}
|
|
if (pskb_trim_rcsum(skb, netoff + len)) {
|
|
kfree_skb(skb);
|
|
return NULL;
|
|
}
|
|
memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
|
|
if (ip_defrag(net, skb, user))
|
|
return NULL;
|
|
skb_clear_hash(skb);
|
|
}
|
|
}
|
|
return skb;
|
|
}
|
|
EXPORT_SYMBOL(ip_check_defrag);
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
static int dist_min;
|
|
|
|
static struct ctl_table ip4_frags_ns_ctl_table[] = {
|
|
{
|
|
.procname = "ipfrag_high_thresh",
|
|
.maxlen = sizeof(unsigned long),
|
|
.mode = 0644,
|
|
.proc_handler = proc_doulongvec_minmax,
|
|
},
|
|
{
|
|
.procname = "ipfrag_low_thresh",
|
|
.maxlen = sizeof(unsigned long),
|
|
.mode = 0644,
|
|
.proc_handler = proc_doulongvec_minmax,
|
|
},
|
|
{
|
|
.procname = "ipfrag_time",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_jiffies,
|
|
},
|
|
{
|
|
.procname = "ipfrag_max_dist",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_minmax,
|
|
.extra1 = &dist_min,
|
|
},
|
|
{ }
|
|
};
|
|
|
|
/* secret interval has been deprecated */
|
|
static int ip4_frags_secret_interval_unused;
|
|
static struct ctl_table ip4_frags_ctl_table[] = {
|
|
{
|
|
.procname = "ipfrag_secret_interval",
|
|
.data = &ip4_frags_secret_interval_unused,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_jiffies,
|
|
},
|
|
{ }
|
|
};
|
|
|
|
static int __net_init ip4_frags_ns_ctl_register(struct net *net)
|
|
{
|
|
struct ctl_table *table;
|
|
struct ctl_table_header *hdr;
|
|
|
|
table = ip4_frags_ns_ctl_table;
|
|
if (!net_eq(net, &init_net)) {
|
|
table = kmemdup(table, sizeof(ip4_frags_ns_ctl_table), GFP_KERNEL);
|
|
if (!table)
|
|
goto err_alloc;
|
|
|
|
}
|
|
table[0].data = &net->ipv4.fqdir->high_thresh;
|
|
table[0].extra1 = &net->ipv4.fqdir->low_thresh;
|
|
table[1].data = &net->ipv4.fqdir->low_thresh;
|
|
table[1].extra2 = &net->ipv4.fqdir->high_thresh;
|
|
table[2].data = &net->ipv4.fqdir->timeout;
|
|
table[3].data = &net->ipv4.fqdir->max_dist;
|
|
|
|
hdr = register_net_sysctl_sz(net, "net/ipv4", table,
|
|
ARRAY_SIZE(ip4_frags_ns_ctl_table));
|
|
if (!hdr)
|
|
goto err_reg;
|
|
|
|
net->ipv4.frags_hdr = hdr;
|
|
return 0;
|
|
|
|
err_reg:
|
|
if (!net_eq(net, &init_net))
|
|
kfree(table);
|
|
err_alloc:
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void __net_exit ip4_frags_ns_ctl_unregister(struct net *net)
|
|
{
|
|
struct ctl_table *table;
|
|
|
|
table = net->ipv4.frags_hdr->ctl_table_arg;
|
|
unregister_net_sysctl_table(net->ipv4.frags_hdr);
|
|
kfree(table);
|
|
}
|
|
|
|
static void __init ip4_frags_ctl_register(void)
|
|
{
|
|
register_net_sysctl(&init_net, "net/ipv4", ip4_frags_ctl_table);
|
|
}
|
|
#else
|
|
static int ip4_frags_ns_ctl_register(struct net *net)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void ip4_frags_ns_ctl_unregister(struct net *net)
|
|
{
|
|
}
|
|
|
|
static void __init ip4_frags_ctl_register(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
static int __net_init ipv4_frags_init_net(struct net *net)
|
|
{
|
|
int res;
|
|
|
|
res = fqdir_init(&net->ipv4.fqdir, &ip4_frags, net);
|
|
if (res < 0)
|
|
return res;
|
|
/* Fragment cache limits.
|
|
*
|
|
* The fragment memory accounting code, (tries to) account for
|
|
* the real memory usage, by measuring both the size of frag
|
|
* queue struct (inet_frag_queue (ipv4:ipq/ipv6:frag_queue))
|
|
* and the SKB's truesize.
|
|
*
|
|
* A 64K fragment consumes 129736 bytes (44*2944)+200
|
|
* (1500 truesize == 2944, sizeof(struct ipq) == 200)
|
|
*
|
|
* We will commit 4MB at one time. Should we cross that limit
|
|
* we will prune down to 3MB, making room for approx 8 big 64K
|
|
* fragments 8x128k.
|
|
*/
|
|
net->ipv4.fqdir->high_thresh = 4 * 1024 * 1024;
|
|
net->ipv4.fqdir->low_thresh = 3 * 1024 * 1024;
|
|
/*
|
|
* Important NOTE! Fragment queue must be destroyed before MSL expires.
|
|
* RFC791 is wrong proposing to prolongate timer each fragment arrival
|
|
* by TTL.
|
|
*/
|
|
net->ipv4.fqdir->timeout = IP_FRAG_TIME;
|
|
|
|
net->ipv4.fqdir->max_dist = 64;
|
|
|
|
res = ip4_frags_ns_ctl_register(net);
|
|
if (res < 0)
|
|
fqdir_exit(net->ipv4.fqdir);
|
|
return res;
|
|
}
|
|
|
|
static void __net_exit ipv4_frags_pre_exit_net(struct net *net)
|
|
{
|
|
fqdir_pre_exit(net->ipv4.fqdir);
|
|
}
|
|
|
|
static void __net_exit ipv4_frags_exit_net(struct net *net)
|
|
{
|
|
ip4_frags_ns_ctl_unregister(net);
|
|
fqdir_exit(net->ipv4.fqdir);
|
|
}
|
|
|
|
static struct pernet_operations ip4_frags_ops = {
|
|
.init = ipv4_frags_init_net,
|
|
.pre_exit = ipv4_frags_pre_exit_net,
|
|
.exit = ipv4_frags_exit_net,
|
|
};
|
|
|
|
|
|
static u32 ip4_key_hashfn(const void *data, u32 len, u32 seed)
|
|
{
|
|
return jhash2(data,
|
|
sizeof(struct frag_v4_compare_key) / sizeof(u32), seed);
|
|
}
|
|
|
|
static u32 ip4_obj_hashfn(const void *data, u32 len, u32 seed)
|
|
{
|
|
const struct inet_frag_queue *fq = data;
|
|
|
|
return jhash2((const u32 *)&fq->key.v4,
|
|
sizeof(struct frag_v4_compare_key) / sizeof(u32), seed);
|
|
}
|
|
|
|
static int ip4_obj_cmpfn(struct rhashtable_compare_arg *arg, const void *ptr)
|
|
{
|
|
const struct frag_v4_compare_key *key = arg->key;
|
|
const struct inet_frag_queue *fq = ptr;
|
|
|
|
return !!memcmp(&fq->key, key, sizeof(*key));
|
|
}
|
|
|
|
static const struct rhashtable_params ip4_rhash_params = {
|
|
.head_offset = offsetof(struct inet_frag_queue, node),
|
|
.key_offset = offsetof(struct inet_frag_queue, key),
|
|
.key_len = sizeof(struct frag_v4_compare_key),
|
|
.hashfn = ip4_key_hashfn,
|
|
.obj_hashfn = ip4_obj_hashfn,
|
|
.obj_cmpfn = ip4_obj_cmpfn,
|
|
.automatic_shrinking = true,
|
|
};
|
|
|
|
void __init ipfrag_init(void)
|
|
{
|
|
ip4_frags.constructor = ip4_frag_init;
|
|
ip4_frags.destructor = ip4_frag_free;
|
|
ip4_frags.qsize = sizeof(struct ipq);
|
|
ip4_frags.frag_expire = ip_expire;
|
|
ip4_frags.frags_cache_name = ip_frag_cache_name;
|
|
ip4_frags.rhash_params = ip4_rhash_params;
|
|
if (inet_frags_init(&ip4_frags))
|
|
panic("IP: failed to allocate ip4_frags cache\n");
|
|
ip4_frags_ctl_register();
|
|
register_pernet_subsys(&ip4_frags_ops);
|
|
}
|