Merge branch 'linus' into timers/core

Reason: Get upstream fixes before adding conflicting code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

16 files changed, 158 insertions, 111 deletions

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 68f6a94f7661..c929d9c1c4b6 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1333,8 +1333,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
                                 iph->frag_off |= htons(IP_MF);
                         offset += (skb->len - skb->mac_len - iph->ihl * 4);
                 } else  {
-                        if (!(iph->frag_off & htons(IP_DF)))
-                                iph->id = htons(id++);
+                        iph->id = htons(id++);
                 }
                 iph->tot_len = htons(skb->len - skb->mac_len);
                 iph->check = 0;
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index f678507bc829..c6287cd978c2 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -587,13 +587,16 @@ static void check_lifetime(struct work_struct *work)
 {
         unsigned long now, next, next_sec, next_sched;
         struct in_ifaddr *ifa;
+        struct hlist_node *n;
         int i;
 
         now = jiffies;
         next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
 
-        rcu_read_lock();
         for (i = 0; i < IN4_ADDR_HSIZE; i++) {
+                bool change_needed = false;
+
+                rcu_read_lock();
                 hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
                         unsigned long age;
 
@@ -606,16 +609,7 @@ static void check_lifetime(struct work_struct *work)
 
                         if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
                             age >= ifa->ifa_valid_lft) {
-                                struct in_ifaddr **ifap ;
-
-                                rtnl_lock();
-                                for (ifap = &ifa->ifa_dev->ifa_list;
-                                     *ifap != NULL; ifap = &ifa->ifa_next) {
-                                        if (*ifap == ifa)
-                                                inet_del_ifa(ifa->ifa_dev,
-                                                             ifap, 1);
-                                }
-                                rtnl_unlock();
+                                change_needed = true;
                         } else if (ifa->ifa_preferred_lft ==
                                    INFINITY_LIFE_TIME) {
                                 continue;
@@ -625,10 +619,8 @@ static void check_lifetime(struct work_struct *work)
                                         next = ifa->ifa_tstamp +
                                                ifa->ifa_valid_lft * HZ;
 
-                                if (!(ifa->ifa_flags & IFA_F_DEPRECATED)) {
-                                        ifa->ifa_flags |= IFA_F_DEPRECATED;
-                                        rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
-                                }
+                                if (!(ifa->ifa_flags & IFA_F_DEPRECATED))
+                                        change_needed = true;
                         } else if (time_before(ifa->ifa_tstamp +
                                                ifa->ifa_preferred_lft * HZ,
                                                next)) {
@@ -636,8 +628,42 @@ static void check_lifetime(struct work_struct *work)
                                        ifa->ifa_preferred_lft * HZ;
                         }
                 }
+                rcu_read_unlock();
+                if (!change_needed)
+                        continue;
+                rtnl_lock();
+                hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
+                        unsigned long age;
+
+                        if (ifa->ifa_flags & IFA_F_PERMANENT)
+                                continue;
+
+                        /* We try to batch several events at once. */
+                        age = (now - ifa->ifa_tstamp +
+                               ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
+
+                        if (ifa->ifa_valid_lft != INFINITY_LIFE_TIME &&
+                            age >= ifa->ifa_valid_lft) {
+                                struct in_ifaddr **ifap;
+
+                                for (ifap = &ifa->ifa_dev->ifa_list;
+                                     *ifap != NULL; ifap = &(*ifap)->ifa_next) {
+                                        if (*ifap == ifa) {
+                                                inet_del_ifa(ifa->ifa_dev,
+                                                             ifap, 1);
+                                                break;
+                                        }
+                                }
+                        } else if (ifa->ifa_preferred_lft !=
+                                   INFINITY_LIFE_TIME &&
+                                   age >= ifa->ifa_preferred_lft &&
+                                   !(ifa->ifa_flags & IFA_F_DEPRECATED)) {
+                                ifa->ifa_flags |= IFA_F_DEPRECATED;
+                                rtmsg_ifa(RTM_NEWADDR, ifa, NULL, 0);
+                        }
+                }
+                rtnl_unlock();
         }
-        rcu_read_unlock();
 
         next_sec = round_jiffies_up(next);
         next_sched = next;
@@ -802,8 +828,12 @@ static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg
                 if (nlh->nlmsg_flags & NLM_F_EXCL ||
                     !(nlh->nlmsg_flags & NLM_F_REPLACE))
                         return -EEXIST;
-
-                set_ifa_lifetime(ifa_existing, valid_lft, prefered_lft);
+                ifa = ifa_existing;
+                set_ifa_lifetime(ifa, valid_lft, prefered_lft);
+                cancel_delayed_work(&check_lifetime_work);
+                schedule_delayed_work(&check_lifetime_work, 0);
+                rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
+                blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
         }
         return 0;
 }
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 3b4f0cd2e63e..4cfe34d4cc96 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -139,8 +139,6 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
 
         /* skb is pure payload to encrypt */
 
-        err = -ENOMEM;
-
         esp = x->data;
         aead = esp->aead;
         alen = crypto_aead_authsize(aead);
@@ -176,8 +174,10 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
         }
 
         tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
-        if (!tmp)
+        if (!tmp) {
+                err = -ENOMEM;
                 goto error;
+        }
 
         seqhi = esp_tmp_seqhi(tmp);
         iv = esp_tmp_iv(aead, tmp, seqhilen);
diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c
index 245ae078a07f..f4fd23de9b13 100644
--- a/net/ipv4/inet_fragment.c
+++ b/net/ipv4/inet_fragment.c
@@ -21,6 +21,7 @@
 #include <linux/rtnetlink.h>
 #include <linux/slab.h>
 
+#include <net/sock.h>
 #include <net/inet_frag.h>
 
 static void inet_frag_secret_rebuild(unsigned long dummy)
@@ -277,6 +278,7 @@ struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
         __releases(&f->lock)
 {
         struct inet_frag_queue *q;
+        int depth = 0;
 
         hlist_for_each_entry(q, &f->hash[hash], list) {
                 if (q->net == nf && f->match(q, key)) {
@@ -284,9 +286,25 @@ struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
                         read_unlock(&f->lock);
                         return q;
                 }
+                depth++;
         }
         read_unlock(&f->lock);
 
-        return inet_frag_create(nf, f, key);
+        if (depth <= INETFRAGS_MAXDEPTH)
+                return inet_frag_create(nf, f, key);
+        else
+                return ERR_PTR(-ENOBUFS);
 }
 EXPORT_SYMBOL(inet_frag_find);
+
+void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q,
+                                   const char *prefix)
+{
+        static const char msg[] = "inet_frag_find: Fragment hash bucket"
+                " list length grew over limit " __stringify(INETFRAGS_MAXDEPTH)
+                ". Dropping fragment.\n";
+
+        if (PTR_ERR(q) == -ENOBUFS)
+                LIMIT_NETDEBUG(KERN_WARNING "%s%s", prefix, msg);
+}
+EXPORT_SYMBOL(inet_frag_maybe_warn_overflow);
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index b6d30acb600c..52c273ea05c3 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -248,8 +248,7 @@ static void ip_expire(unsigned long arg)
                 if (!head->dev)
                         goto out_rcu_unlock;
 
-                /* skb dst is stale, drop it, and perform route lookup again */
-                skb_dst_drop(head);
+                /* skb has no dst, perform route lookup again */
                 iph = ip_hdr(head);
                 err = ip_route_input_noref(head, iph->daddr, iph->saddr,
                                            iph->tos, head->dev);
@@ -292,14 +291,11 @@ static inline struct ipq *ip_find(struct net *net, struct iphdr *iph, u32 user)
         hash = ipqhashfn(iph->id, iph->saddr, iph->daddr, iph->protocol);
 
         q = inet_frag_find(&net->ipv4.frags, &ip4_frags, &arg, hash);
-        if (q == NULL)
-                goto out_nomem;
-
+        if (IS_ERR_OR_NULL(q)) {
+                inet_frag_maybe_warn_overflow(q, pr_fmt());
+                return NULL;
+        }
         return container_of(q, struct ipq, q);
-
-out_nomem:
-        LIMIT_NETDEBUG(KERN_ERR pr_fmt("ip_frag_create: no memory left !\n"));
-        return NULL;
 }
 
 /* Is the fragment too far ahead to be part of ipq? */
@@ -526,9 +522,16 @@ found:
                 qp->q.max_size = skb->len + ihl;
 
         if (qp->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
-            qp->q.meat == qp->q.len)
-                return ip_frag_reasm(qp, prev, dev);
+            qp->q.meat == qp->q.len) {
+                unsigned long orefdst = skb->_skb_refdst;
+
+                skb->_skb_refdst = 0UL;
+                err = ip_frag_reasm(qp, prev, dev);
+                skb->_skb_refdst = orefdst;
+                return err;
+        }
 
+        skb_dst_drop(skb);
         inet_frag_lru_move(&qp->q);
         return -EINPROGRESS;
 
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index d0ef0e674ec5..91d66dbde9c0 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -798,10 +798,7 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
 
         if (dev->header_ops && dev->type == ARPHRD_IPGRE) {
                 gre_hlen = 0;
-                if (skb->protocol == htons(ETH_P_IP))
-                        tiph = (const struct iphdr *)skb->data;
-                else
-                        tiph = &tunnel->parms.iph;
+                tiph = (const struct iphdr *)skb->data;
         } else {
                 gre_hlen = tunnel->hlen;
                 tiph = &tunnel->parms.iph;
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index 310a3647c83d..ec7264514a82 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -370,7 +370,6 @@ int ip_options_compile(struct net *net,
                                 }
                                 switch (optptr[3]&0xF) {
                                       case IPOPT_TS_TSONLY:
-                                        opt->ts = optptr - iph;
                                         if (skb)
                                                 timeptr = &optptr[optptr[2]-1];
                                         opt->ts_needtime = 1;
@@ -381,7 +380,6 @@ int ip_options_compile(struct net *net,
                                                 pp_ptr = optptr + 2;
                                                 goto error;
                                         }
-                                        opt->ts = optptr - iph;
                                         if (rt)  {
                                                 spec_dst_fill(&spec_dst, skb);
                                                 memcpy(&optptr[optptr[2]-1], &spec_dst, 4);
@@ -396,7 +394,6 @@ int ip_options_compile(struct net *net,
                                                 pp_ptr = optptr + 2;
                                                 goto error;
                                         }
-                                        opt->ts = optptr - iph;
                                         {
                                                 __be32 addr;
                                                 memcpy(&addr, &optptr[optptr[2]-1], 4);
@@ -429,12 +426,12 @@ int ip_options_compile(struct net *net,
                                         pp_ptr = optptr + 3;
                                         goto error;
                                 }
-                                opt->ts = optptr - iph;
                                 if (skb) {
                                         optptr[3] = (optptr[3]&0xF)|((overflow+1)<<4);
                                         opt->is_changed = 1;
                                 }
                         }
+                        opt->ts = optptr - iph;
                         break;
                       case IPOPT_RA:
                         if (optlen < 4) {
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 98cbc6877019..bf6c5cf31aed 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -1522,7 +1522,8 @@ static int __init ip_auto_config(void)
                 }
         for (i++; i < CONF_NAMESERVERS_MAX; i++)
                 if (ic_nameservers[i] != NONE)
-                        pr_cont(", nameserver%u=%pI4\n", i, &ic_nameservers[i]);
+                        pr_cont(", nameserver%u=%pI4", i, &ic_nameservers[i]);
+        pr_cont("\n");
 #endif /* !SILENT */
 
         return 0;
diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig
index ce2d43e1f09f..0d755c50994b 100644
--- a/net/ipv4/netfilter/Kconfig
+++ b/net/ipv4/netfilter/Kconfig
@@ -36,19 +36,6 @@ config NF_CONNTRACK_PROC_COMPAT
 
           If unsure, say Y.
 
-config IP_NF_QUEUE
-        tristate "IP Userspace queueing via NETLINK (OBSOLETE)"
-        depends on NETFILTER_ADVANCED
-        help
-          Netfilter has the ability to queue packets to user space: the
-          netlink device can be used to access them using this driver.
-
-          This option enables the old IPv4-only "ip_queue" implementation
-          which has been obsoleted by the new "nfnetlink_queue" code (see
-          CONFIG_NETFILTER_NETLINK_QUEUE).
-
-          To compile it as a module, choose M here.  If unsure, say N.
-
 config IP_NF_IPTABLES
         tristate "IP tables support (required for filtering/masq/NAT)"
         default m if NETFILTER_ADVANCED=n
diff --git a/net/ipv4/netfilter/ipt_rpfilter.c b/net/ipv4/netfilter/ipt_rpfilter.c
index c30130062cd6..c49dcd0284a0 100644
--- a/net/ipv4/netfilter/ipt_rpfilter.c
+++ b/net/ipv4/netfilter/ipt_rpfilter.c
@@ -66,6 +66,12 @@ static bool rpfilter_lookup_reverse(struct flowi4 *fl4,
         return dev_match;
 }
 
+static bool rpfilter_is_local(const struct sk_buff *skb)
+{
+        const struct rtable *rt = skb_rtable(skb);
+        return rt && (rt->rt_flags & RTCF_LOCAL);
+}
+
 static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par)
 {
         const struct xt_rpfilter_info *info;
@@ -76,7 +82,7 @@ static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par)
         info = par->matchinfo;
         invert = info->flags & XT_RPFILTER_INVERT;
 
-        if (par->in->flags & IFF_LOOPBACK)
+        if (rpfilter_is_local(skb))
                 return true ^ invert;
 
         iph = ip_hdr(skb);
diff --git a/net/ipv4/syncookies.c b/net/ipv4/syncookies.c
index ef54377fb11c..397e0f69435f 100644
--- a/net/ipv4/syncookies.c
+++ b/net/ipv4/syncookies.c
@@ -349,8 +349,8 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
          * hasn't changed since we received the original syn, but I see
          * no easy way to do this.
          */
-        flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk),
-                           RT_SCOPE_UNIVERSE, IPPROTO_TCP,
+        flowi4_init_output(&fl4, sk->sk_bound_dev_if, sk->sk_mark,
+                           RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, IPPROTO_TCP,
                            inet_sk_flowi_flags(sk),
                            (opt && opt->srr) ? opt->faddr : ireq->rmt_addr,
                            ireq->loc_addr, th->source, th->dest);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 47e854fcae24..e22020790709 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -775,7 +775,7 @@ struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp)
                          * Make sure that we have exactly size bytes
                          * available to the caller, no more, no less.
                          */
-                        skb->avail_size = size;
+                        skb->reserved_tailroom = skb->end - skb->tail - size;
                         return skb;
                 }
                 __kfree_skb(skb);
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 0d9bdacce99f..13b9c08fc158 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -113,6 +113,7 @@ int sysctl_tcp_early_retrans __read_mostly = 2;
 #define FLAG_DSACKING_ACK       0x800 /* SACK blocks contained D-SACK info */
 #define FLAG_NONHEAD_RETRANS_ACKED      0x1000 /* Non-head rexmitted data was ACKed */
 #define FLAG_SACK_RENEGING      0x2000 /* snd_una advanced to a sacked seq */
+#define FLAG_UPDATE_TS_RECENT   0x4000 /* tcp_replace_ts_recent() */
 
 #define FLAG_ACKED              (FLAG_DATA_ACKED|FLAG_SYN_ACKED)
 #define FLAG_NOT_DUP            (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED)
@@ -2059,11 +2060,8 @@ void tcp_enter_loss(struct sock *sk, int how)
         if (tcp_is_reno(tp))
                 tcp_reset_reno_sack(tp);
 
-        if (!how) {
-                /* Push undo marker, if it was plain RTO and nothing
-                 * was retransmitted. */
-                tp->undo_marker = tp->snd_una;
-        } else {
+        tp->undo_marker = tp->snd_una;
+        if (how) {
                 tp->sacked_out = 0;
                 tp->fackets_out = 0;
         }
@@ -3567,6 +3565,27 @@ static void tcp_send_challenge_ack(struct sock *sk)
         }
 }
 
+static void tcp_store_ts_recent(struct tcp_sock *tp)
+{
+        tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval;
+        tp->rx_opt.ts_recent_stamp = get_seconds();
+}
+
+static void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq)
+{
+        if (tp->rx_opt.saw_tstamp && !after(seq, tp->rcv_wup)) {
+                /* PAWS bug workaround wrt. ACK frames, the PAWS discard
+                 * extra check below makes sure this can only happen
+                 * for pure ACK frames.  -DaveM
+                 *
+                 * Not only, also it occurs for expired timestamps.
+                 */
+
+                if (tcp_paws_check(&tp->rx_opt, 0))
+                        tcp_store_ts_recent(tp);
+        }
+}
+
 /* This routine deals with incoming acks, but not outgoing ones. */
 static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 {
@@ -3610,6 +3629,12 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
         prior_fackets = tp->fackets_out;
         prior_in_flight = tcp_packets_in_flight(tp);
 
+        /* ts_recent update must be made after we are sure that the packet
+         * is in window.
+         */
+        if (flag & FLAG_UPDATE_TS_RECENT)
+                tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
+
         if (!(flag & FLAG_SLOWPATH) && after(ack, prior_snd_una)) {
                 /* Window is constant, pure forward advance.
                  * No more checks are required.
@@ -3930,27 +3955,6 @@ const u8 *tcp_parse_md5sig_option(const struct tcphdr *th)
 EXPORT_SYMBOL(tcp_parse_md5sig_option);
 #endif
 
-static inline void tcp_store_ts_recent(struct tcp_sock *tp)
-{
-        tp->rx_opt.ts_recent = tp->rx_opt.rcv_tsval;
-        tp->rx_opt.ts_recent_stamp = get_seconds();
-}
-
-static inline void tcp_replace_ts_recent(struct tcp_sock *tp, u32 seq)
-{
-        if (tp->rx_opt.saw_tstamp && !after(seq, tp->rcv_wup)) {
-                /* PAWS bug workaround wrt. ACK frames, the PAWS discard
-                 * extra check below makes sure this can only happen
-                 * for pure ACK frames.  -DaveM
-                 *
-                 * Not only, also it occurs for expired timestamps.
-                 */
-
-                if (tcp_paws_check(&tp->rx_opt, 0))
-                        tcp_store_ts_recent(tp);
-        }
-}
-
 /* Sorry, PAWS as specified is broken wrt. pure-ACKs -DaveM
  *
  * It is not fatal. If this ACK does _not_ change critical state (seqs, window)
@@ -5546,14 +5550,9 @@ slow_path:
                 return 0;
 
 step5:
-        if (tcp_ack(sk, skb, FLAG_SLOWPATH) < 0)
+        if (tcp_ack(sk, skb, FLAG_SLOWPATH | FLAG_UPDATE_TS_RECENT) < 0)
                 goto discard;
 
-        /* ts_recent update must be made after we are sure that the packet
-         * is in window.
-         */
-        tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
-
         tcp_rcv_rtt_measure_ts(sk, skb);
 
         /* Process urgent data. */
@@ -5989,7 +5988,8 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 
         /* step 5: check the ACK field */
         if (true) {
-                int acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH) > 0;
+                int acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH |
+                                                  FLAG_UPDATE_TS_RECENT) > 0;
 
                 switch (sk->sk_state) {
                 case TCP_SYN_RECV:
@@ -6140,11 +6140,6 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
                 }
         }
 
-        /* ts_recent update must be made after we are sure that the packet
-         * is in window.
-         */
-        tcp_replace_ts_recent(tp, TCP_SKB_CB(skb)->seq);
-
         /* step 6: check the URG bit */
         tcp_urg(sk, skb, th);
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 4a8ec457310f..d09203c63264 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -274,13 +274,6 @@ static void tcp_v4_mtu_reduced(struct sock *sk)
         struct inet_sock *inet = inet_sk(sk);
         u32 mtu = tcp_sk(sk)->mtu_info;
 
-        /* We are not interested in TCP_LISTEN and open_requests (SYN-ACKs
-         * send out by Linux are always <576bytes so they should go through
-         * unfragmented).
-         */
-        if (sk->sk_state == TCP_LISTEN)
-                return;
-
         dst = inet_csk_update_pmtu(sk, mtu);
         if (!dst)
                 return;
@@ -408,6 +401,13 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
                         goto out;
 
                 if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */
+                        /* We are not interested in TCP_LISTEN and open_requests
+                         * (SYN-ACKs send out by Linux are always <576bytes so
+                         * they should go through unfragmented).
+                         */
+                        if (sk->sk_state == TCP_LISTEN)
+                                goto out;
+
                         tp->mtu_info = info;
                         if (!sock_owned_by_user(sk)) {
                                 tcp_v4_mtu_reduced(sk);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e2b4461074da..509912a5ff98 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1298,7 +1298,6 @@ static void __pskb_trim_head(struct sk_buff *skb, int len)
         eat = min_t(int, len, skb_headlen(skb));
         if (eat) {
                 __skb_pull(skb, eat);
-                skb->avail_size -= eat;
                 len -= eat;
                 if (!len)
                         return;
@@ -1810,8 +1809,11 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
                         goto send_now;
         }
 
-        /* Ok, it looks like it is advisable to defer.  */
-        tp->tso_deferred = 1 | (jiffies << 1);
+        /* Ok, it looks like it is advisable to defer.
+         * Do not rearm the timer if already set to not break TCP ACK clocking.
+         */
+        if (!tp->tso_deferred)
+                tp->tso_deferred = 1 | (jiffies << 1);
 
         return true;
 
@@ -2386,8 +2388,12 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
          */
         TCP_SKB_CB(skb)->when = tcp_time_stamp;
 
-        /* make sure skb->data is aligned on arches that require it */
-        if (unlikely(NET_IP_ALIGN && ((unsigned long)skb->data & 3))) {
+        /* make sure skb->data is aligned on arches that require it
+         * and check if ack-trimming & collapsing extended the headroom
+         * beyond what csum_start can cover.
+         */
+        if (unlikely((NET_IP_ALIGN && ((unsigned long)skb->data & 3)) ||
+                     skb_headroom(skb) >= 0xFFFF)) {
                 struct sk_buff *nskb = __pskb_copy(skb, MAX_TCP_HEADER,
                                                    GFP_ATOMIC);
                 return nskb ? tcp_transmit_skb(sk, nskb, 0, GFP_ATOMIC) :
@@ -2707,6 +2713,7 @@ struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst,
         skb_reserve(skb, MAX_TCP_HEADER);
 
         skb_dst_set(skb, dst);
+        security_skb_owned_by(skb, sk);
 
         mss = dst_metric_advmss(dst);
         if (tp->rx_opt.user_mss && tp->rx_opt.user_mss < mss)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 265c42cf963c..0a073a263720 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1762,9 +1762,16 @@ int udp_rcv(struct sk_buff *skb)
 
 void udp_destroy_sock(struct sock *sk)
 {
+        struct udp_sock *up = udp_sk(sk);
         bool slow = lock_sock_fast(sk);
         udp_flush_pending_frames(sk);
         unlock_sock_fast(sk, slow);
+        if (static_key_false(&udp_encap_needed) && up->encap_type) {
+                void (*encap_destroy)(struct sock *sk);
+                encap_destroy = ACCESS_ONCE(up->encap_destroy);
+                if (encap_destroy)
+                        encap_destroy(sk);
+        }
 }
 
 /*