17 files changed, 87 insertions, 66 deletions

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index cb5290b8c428..5221f975a4cc 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -349,7 +349,7 @@ static LIST_HEAD(cleanup_list);  /* Must hold cleanup_list_lock to touch */
 static void cleanup_net(struct work_struct *work)
 {
         const struct pernet_operations *ops;
-        struct net *net, *tmp;
+        struct net *net, *tmp, *peer;
         struct list_head net_kill_list;
         LIST_HEAD(net_exit_list);
 
@@ -365,14 +365,6 @@ static void cleanup_net(struct work_struct *work)
         list_for_each_entry(net, &net_kill_list, cleanup_list) {
                 list_del_rcu(&net->list);
                 list_add_tail(&net->exit_list, &net_exit_list);
-                for_each_net(tmp) {
-                        int id = __peernet2id(tmp, net, false);
-
-                        if (id >= 0)
-                                idr_remove(&tmp->netns_ids, id);
-                }
-                idr_destroy(&net->netns_ids);
-
         }
         rtnl_unlock();
 
@@ -398,12 +390,26 @@ static void cleanup_net(struct work_struct *work)
          */
         rcu_barrier();
 
+        rtnl_lock();
         /* Finally it is safe to free my network namespace structure */
         list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
+                /* Unreference net from all peers (no need to loop over
+                 * net_exit_list because idr_destroy() will be called for each
+                 * element of this list.
+                 */
+                for_each_net(peer) {
+                        int id = __peernet2id(peer, net, false);
+
+                        if (id >= 0)
+                                idr_remove(&peer->netns_ids, id);
+                }
+                idr_destroy(&net->netns_ids);
+
                 list_del_init(&net->exit_list);
                 put_user_ns(net->user_ns);
                 net_drop_ns(net);
         }
+        rtnl_unlock();
 }
 static DECLARE_WORK(net_cleanup_work, cleanup_net);
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index ee0608bb3bc0..7ebed55b5f7d 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1932,10 +1932,10 @@ static int rtnl_group_changelink(const struct sk_buff *skb,
                 struct ifinfomsg *ifm,
                 struct nlattr **tb)
 {
-        struct net_device *dev;
+        struct net_device *dev, *aux;
         int err;
 
-        for_each_netdev(net, dev) {
+        for_each_netdev_safe(net, dev, aux) {
                 if (dev->group == group) {
                         err = do_setlink(skb, dev, ifm, tb, NULL, 0);
                         if (err < 0)
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 9d78427652d2..92825443fad6 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -268,7 +268,7 @@ static int __net_init ipmr_rules_init(struct net *net)
         return 0;
 
 err2:
-        kfree(mrt);
+        ipmr_free_table(mrt);
 err1:
         fib_rules_unregister(ops);
         return err;
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 5a2dfed4783b..f1756ee02207 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1518,7 +1518,7 @@ void tcp_v4_early_demux(struct sk_buff *skb)
                 skb->sk = sk;
                 skb->destructor = sock_edemux;
                 if (sk->sk_state != TCP_TIME_WAIT) {
-                        struct dst_entry *dst = sk->sk_rx_dst;
+                        struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst);
 
                         if (dst)
                                 dst = dst_check(dst, 0);
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 34b682617f50..52028f449a89 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -252,7 +252,7 @@ static int __net_init ip6mr_rules_init(struct net *net)
         return 0;
 
 err2:
-        kfree(mrt);
+        ip6mr_free_table(mrt);
 err1:
         fib_rules_unregister(ops);
         return err;
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 471ed24aabae..14ecdaf06bf7 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1218,7 +1218,14 @@ static void ndisc_router_discovery(struct sk_buff *skb)
         if (rt)
                 rt6_set_expires(rt, jiffies + (HZ * lifetime));
         if (ra_msg->icmph.icmp6_hop_limit) {
-                in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+                /* Only set hop_limit on the interface if it is higher than
+                 * the current hop_limit.
+                 */
+                if (in6_dev->cnf.hop_limit < ra_msg->icmph.icmp6_hop_limit) {
+                        in6_dev->cnf.hop_limit = ra_msg->icmph.icmp6_hop_limit;
+                } else {
+                        ND_PRINTK(2, warn, "RA: Got route advertisement with lower hop_limit than current\n");
+                }
                 if (rt)
                         dst_metric_set(&rt->dst, RTAX_HOPLIMIT,
                                        ra_msg->icmph.icmp6_hop_limit);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 5d46832c6f72..1f5e62229aaa 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1411,6 +1411,15 @@ static void tcp_v6_fill_cb(struct sk_buff *skb, const struct ipv6hdr *hdr,
         TCP_SKB_CB(skb)->sacked = 0;
 }
 
+static void tcp_v6_restore_cb(struct sk_buff *skb)
+{
+        /* We need to move header back to the beginning if xfrm6_policy_check()
+         * and tcp_v6_fill_cb() are going to be called again.
+         */
+        memmove(IP6CB(skb), &TCP_SKB_CB(skb)->header.h6,
+                sizeof(struct inet6_skb_parm));
+}
+
 static int tcp_v6_rcv(struct sk_buff *skb)
 {
         const struct tcphdr *th;
@@ -1543,6 +1552,7 @@ do_time_wait:
                         inet_twsk_deschedule(tw, &tcp_death_row);
                         inet_twsk_put(tw);
                         sk = sk2;
+                        tcp_v6_restore_cb(skb);
                         goto process;
                 }
                 /* Fall through to ACK */
@@ -1551,6 +1561,7 @@ do_time_wait:
                 tcp_v6_timewait_ack(sk, skb);
                 break;
         case TCP_TW_RST:
+                tcp_v6_restore_cb(skb);
                 goto no_tcp_socket;
         case TCP_TW_SUCCESS:
                 ;
@@ -1585,7 +1596,7 @@ static void tcp_v6_early_demux(struct sk_buff *skb)
                 skb->sk = sk;
                 skb->destructor = sock_edemux;
                 if (sk->sk_state != TCP_TIME_WAIT) {
-                        struct dst_entry *dst = sk->sk_rx_dst;
+                        struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst);
 
                         if (dst)
                                 dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie);
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 2e9953b2db84..53d931172088 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1114,10 +1114,8 @@ static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
                         noblock, &err);
         else
                 skb = sock_alloc_send_skb(sk, len, noblock, &err);
-        if (!skb) {
-                err = -ENOMEM;
+        if (!skb)
                 goto out;
-        }
         if (iucv->transport == AF_IUCV_TRANS_HIPER)
                 skb_reserve(skb, sizeof(struct af_iucv_trans_hdr) + ETH_HLEN);
         if (memcpy_from_msg(skb_put(skb, len), msg, len)) {
diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index a48bad468880..7702978a4c99 100644
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -49,8 +49,6 @@ static void ieee80211_free_tid_rx(struct rcu_head *h)
                 container_of(h, struct tid_ampdu_rx, rcu_head);
         int i;
 
-        del_timer_sync(&tid_rx->reorder_timer);
-
         for (i = 0; i < tid_rx->buf_size; i++)
                 __skb_queue_purge(&tid_rx->reorder_buf[i]);
         kfree(tid_rx->reorder_buf);
@@ -93,6 +91,12 @@ void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
 
         del_timer_sync(&tid_rx->session_timer);
 
+        /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
+        spin_lock_bh(&tid_rx->reorder_lock);
+        tid_rx->removed = true;
+        spin_unlock_bh(&tid_rx->reorder_lock);
+        del_timer_sync(&tid_rx->reorder_timer);
+
         call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
 }
 
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 944bdc04e913..1eb730bf8752 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -873,9 +873,10 @@ static void ieee80211_sta_reorder_release(struct ieee80211_sub_if_data *sdata,
 
  set_release_timer:
 
-                mod_timer(&tid_agg_rx->reorder_timer,
-                          tid_agg_rx->reorder_time[j] + 1 +
-                          HT_RX_REORDER_BUF_TIMEOUT);
+                if (!tid_agg_rx->removed)
+                        mod_timer(&tid_agg_rx->reorder_timer,
+                                  tid_agg_rx->reorder_time[j] + 1 +
+                                  HT_RX_REORDER_BUF_TIMEOUT);
         } else {
                 del_timer(&tid_agg_rx->reorder_timer);
         }
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 925e68fe64c7..fb0fc1302a58 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -175,6 +175,7 @@ struct tid_ampdu_tx {
  * @reorder_lock: serializes access to reorder buffer, see below.
  * @auto_seq: used for offloaded BA sessions to automatically pick head_seq_and
  *      and ssn.
+ * @removed: this session is removed (but might have been found due to RCU)
  *
  * This structure's lifetime is managed by RCU, assignments to
  * the array holding it must hold the aggregation mutex.
@@ -199,6 +200,7 @@ struct tid_ampdu_rx {
         u16 timeout;
         u8 dialog_token;
         bool auto_seq;
+        bool removed;
 };
 
 /**
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index ec2954ffc690..067a3fff1d2c 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -274,10 +274,8 @@ void ovs_vport_del(struct vport *vport)
         ASSERT_OVSL();
 
         hlist_del_rcu(&vport->hash_node);
-
-        vport->ops->destroy(vport);
-
         module_put(vport->ops->owner);
+        vport->ops->destroy(vport);
 }
 
 /**
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 612aa73bbc60..e6ce1517367f 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -303,9 +303,7 @@ static int rpc_client_register(struct rpc_clnt *clnt,
         struct super_block *pipefs_sb;
         int err;
 
-        err = rpc_clnt_debugfs_register(clnt);
-        if (err)
-                return err;
+        rpc_clnt_debugfs_register(clnt);
 
         pipefs_sb = rpc_get_sb_net(net);
         if (pipefs_sb) {
diff --git a/net/sunrpc/debugfs.c b/net/sunrpc/debugfs.c
index e811f390f9f6..82962f7e6e88 100644
--- a/net/sunrpc/debugfs.c
+++ b/net/sunrpc/debugfs.c
@@ -129,48 +129,52 @@ static const struct file_operations tasks_fops = {
         .release        = tasks_release,
 };
 
-int
+void
 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
 {
-        int len, err;
+        int len;
         char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
+        struct rpc_xprt *xprt;
 
         /* Already registered? */
-        if (clnt->cl_debugfs)
-                return 0;
+        if (clnt->cl_debugfs || !rpc_clnt_dir)
+                return;
 
         len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
         if (len >= sizeof(name))
-                return -EINVAL;
+                return;
 
         /* make the per-client dir */
         clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
         if (!clnt->cl_debugfs)
-                return -ENOMEM;
+                return;
 
         /* make tasks file */
-        err = -ENOMEM;
         if (!debugfs_create_file("tasks", S_IFREG | S_IRUSR, clnt->cl_debugfs,
                                  clnt, &tasks_fops))
                 goto out_err;
 
-        err = -EINVAL;
         rcu_read_lock();
+        xprt = rcu_dereference(clnt->cl_xprt);
+        /* no "debugfs" dentry? Don't bother with the symlink. */
+        if (!xprt->debugfs) {
+                rcu_read_unlock();
+                return;
+        }
         len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
-                        rcu_dereference(clnt->cl_xprt)->debugfs->d_name.name);
+                        xprt->debugfs->d_name.name);
         rcu_read_unlock();
+
         if (len >= sizeof(name))
                 goto out_err;
 
-        err = -ENOMEM;
         if (!debugfs_create_symlink("xprt", clnt->cl_debugfs, name))
                 goto out_err;
 
-        return 0;
+        return;
 out_err:
         debugfs_remove_recursive(clnt->cl_debugfs);
         clnt->cl_debugfs = NULL;
-        return err;
 }
 
 void
@@ -226,33 +230,33 @@ static const struct file_operations xprt_info_fops = {
         .release        = xprt_info_release,
 };
 
-int
+void
 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
 {
         int len, id;
         static atomic_t cur_id;
         char            name[9]; /* 8 hex digits + NULL term */
 
+        if (!rpc_xprt_dir)
+                return;
+
         id = (unsigned int)atomic_inc_return(&cur_id);
 
         len = snprintf(name, sizeof(name), "%x", id);
         if (len >= sizeof(name))
-                return -EINVAL;
+                return;
 
         /* make the per-client dir */
         xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
         if (!xprt->debugfs)
-                return -ENOMEM;
+                return;
 
         /* make tasks file */
         if (!debugfs_create_file("info", S_IFREG | S_IRUSR, xprt->debugfs,
                                  xprt, &xprt_info_fops)) {
                 debugfs_remove_recursive(xprt->debugfs);
                 xprt->debugfs = NULL;
-                return -ENOMEM;
         }
-
-        return 0;
 }
 
 void
@@ -266,14 +270,17 @@ void __exit
 sunrpc_debugfs_exit(void)
 {
         debugfs_remove_recursive(topdir);
+        topdir = NULL;
+        rpc_clnt_dir = NULL;
+        rpc_xprt_dir = NULL;
 }
 
-int __init
+void __init
 sunrpc_debugfs_init(void)
 {
         topdir = debugfs_create_dir("sunrpc", NULL);
         if (!topdir)
-                goto out;
+                return;
 
         rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
         if (!rpc_clnt_dir)
@@ -283,10 +290,9 @@ sunrpc_debugfs_init(void)
         if (!rpc_xprt_dir)
                 goto out_remove;
 
-        return 0;
+        return;
 out_remove:
         debugfs_remove_recursive(topdir);
         topdir = NULL;
-out:
-        return -ENOMEM;
+        rpc_clnt_dir = NULL;
 }
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index e37fbed87956..ee5d3d253102 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -98,10 +98,7 @@ init_sunrpc(void)
         if (err)
                 goto out4;
 
-        err = sunrpc_debugfs_init();
-        if (err)
-                goto out5;
-
+        sunrpc_debugfs_init();
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
         rpc_register_sysctl();
 #endif
@@ -109,8 +106,6 @@ init_sunrpc(void)
         init_socket_xprt();     /* clnt sock transport */
         return 0;
 
-out5:
-        unregister_rpc_pipefs();
 out4:
         unregister_pernet_subsys(&sunrpc_net_ops);
 out3:
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index e3015aede0d9..9949722d99ce 100644
--- a/net/sunrpc/xprt.c
+++ b/net/sunrpc/xprt.c
@@ -1331,7 +1331,6 @@ static void xprt_init(struct rpc_xprt *xprt, struct net *net)
  */
 struct rpc_xprt *xprt_create_transport(struct xprt_create *args)
 {
-        int err;
         struct rpc_xprt *xprt;
         struct xprt_class *t;
 
@@ -1372,11 +1371,7 @@ found:
                 return ERR_PTR(-ENOMEM);
         }
 
-        err = rpc_xprt_debugfs_register(xprt);
-        if (err) {
-                xprt_destroy(xprt);
-                return ERR_PTR(err);
-        }
+        rpc_xprt_debugfs_register(xprt);
 
         dprintk("RPC:       created transport %p with %u slots\n", xprt,
                         xprt->max_reqs);
diff --git a/net/tipc/core.c b/net/tipc/core.c
index 935205e6bcfe..be1c9fa60b09 100644
--- a/net/tipc/core.c
+++ b/net/tipc/core.c
@@ -152,11 +152,11 @@ out_netlink:
 static void __exit tipc_exit(void)
 {
         tipc_bearer_cleanup();
+        unregister_pernet_subsys(&tipc_net_ops);
         tipc_netlink_stop();
         tipc_netlink_compat_stop();
         tipc_socket_stop();
         tipc_unregister_sysctl();
-        unregister_pernet_subsys(&tipc_net_ops);
 
         pr_info("Deactivated\n");
 }