Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 510 insertions, 0 deletions

diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
new file mode 100644
index 000000000..083f7a8d9
--- /dev/null
+++ b/net/openvswitch/vport.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2007-2014 Nicira, Inc.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/if.h>
+#include <linux/if_vlan.h>
+#include <linux/jhash.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/percpu.h>
+#include <linux/rcupdate.h>
+#include <linux/rtnetlink.h>
+#include <linux/compat.h>
+#include <net/net_namespace.h>
+#include <linux/module.h>
+
+#include "datapath.h"
+#include "vport.h"
+#include "vport-internal_dev.h"
+
+static LIST_HEAD(vport_ops_list);
+
+/* Protected by RCU read lock for reading, ovs_mutex for writing. */
+static struct hlist_head *dev_table;
+#define VPORT_HASH_BUCKETS 1024
+
+/**
+ *	ovs_vport_init - initialize vport subsystem
+ *
+ * Called at module load time to initialize the vport subsystem.
+ */
+int ovs_vport_init(void)
+{
+	dev_table = kzalloc_objs(struct hlist_head, VPORT_HASH_BUCKETS);
+	if (!dev_table)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/**
+ *	ovs_vport_exit - shutdown vport subsystem
+ *
+ * Called at module exit time to shutdown the vport subsystem.
+ */
+void ovs_vport_exit(void)
+{
+	kfree(dev_table);
+}
+
+static struct hlist_head *hash_bucket(const struct net *net, const char *name)
+{
+	unsigned int hash = jhash(name, strlen(name), (unsigned long) net);
+	return &dev_table[hash & (VPORT_HASH_BUCKETS - 1)];
+}
+
+int ovs_vport_ops_register(struct vport_ops *ops)
+{
+	int err = -EEXIST;
+	struct vport_ops *o;
+
+	ovs_lock();
+	list_for_each_entry(o, &vport_ops_list, list)
+		if (ops->type == o->type)
+			goto errout;
+
+	list_add_tail(&ops->list, &vport_ops_list);
+	err = 0;
+errout:
+	ovs_unlock();
+	return err;
+}
+
+void ovs_vport_ops_unregister(struct vport_ops *ops)
+{
+	ovs_lock();
+	list_del(&ops->list);
+	ovs_unlock();
+}
+
+/**
+ *	ovs_vport_locate - find a port that has already been created
+ *
+ * @net: network namespace
+ * @name: name of port to find
+ *
+ * Must be called with ovs or RCU read lock.
+ */
+struct vport *ovs_vport_locate(const struct net *net, const char *name)
+{
+	struct hlist_head *bucket = hash_bucket(net, name);
+	struct vport *vport;
+
+	hlist_for_each_entry_rcu(vport, bucket, hash_node,
+				 lockdep_ovsl_is_held())
+		if (!strcmp(name, ovs_vport_name(vport)) &&
+		    net_eq(ovs_dp_get_net(vport->dp), net))
+			return vport;
+
+	return NULL;
+}
+
+/**
+ *	ovs_vport_alloc - allocate and initialize new vport
+ *
+ * @priv_size: Size of private data area to allocate.
+ * @ops: vport device ops
+ * @parms: information about new vport.
+ *
+ * Allocate and initialize a new vport defined by @ops.  The vport will contain
+ * a private data area of size @priv_size that can be accessed using
+ * vport_priv().  Some parameters of the vport will be initialized from @parms.
+ * @vports that are no longer needed should be released with
+ * vport_free().
+ */
+struct vport *ovs_vport_alloc(int priv_size, const struct vport_ops *ops,
+			      const struct vport_parms *parms)
+{
+	struct vport *vport;
+	size_t alloc_size;
+	int err;
+
+	alloc_size = sizeof(struct vport);
+	if (priv_size) {
+		alloc_size = ALIGN(alloc_size, VPORT_ALIGN);
+		alloc_size += priv_size;
+	}
+
+	vport = kzalloc(alloc_size, GFP_KERNEL);
+	if (!vport)
+		return ERR_PTR(-ENOMEM);
+
+	vport->upcall_stats = netdev_alloc_pcpu_stats(struct vport_upcall_stats_percpu);
+	if (!vport->upcall_stats) {
+		err = -ENOMEM;
+		goto err_kfree_vport;
+	}
+
+	vport->dp = parms->dp;
+	vport->port_no = parms->port_no;
+	vport->ops = ops;
+	INIT_HLIST_NODE(&vport->dp_hash_node);
+
+	if (ovs_vport_set_upcall_portids(vport, parms->upcall_portids)) {
+		err = -EINVAL;
+		goto err_free_percpu;
+	}
+
+	return vport;
+
+err_free_percpu:
+	free_percpu(vport->upcall_stats);
+err_kfree_vport:
+	kfree(vport);
+	return ERR_PTR(err);
+}
+
+/**
+ *	ovs_vport_free - uninitialize and free vport
+ *
+ * @vport: vport to free
+ *
+ * Frees a vport allocated with vport_alloc() when it is no longer needed.
+ *
+ * The caller must ensure that an RCU grace period has passed since the last
+ * time @vport was in a datapath.
+ */
+void ovs_vport_free(struct vport *vport)
+{
+	/* vport is freed from RCU callback or error path, Therefore
+	 * it is safe to use raw dereference.
+	 */
+	kfree(rcu_dereference_raw(vport->upcall_portids));
+	free_percpu(vport->upcall_stats);
+	kfree(vport);
+}
+
+static struct vport_ops *ovs_vport_lookup(const struct vport_parms *parms)
+{
+	struct vport_ops *ops;
+
+	list_for_each_entry(ops, &vport_ops_list, list)
+		if (ops->type == parms->type)
+			return ops;
+
+	return NULL;
+}
+
+/**
+ *	ovs_vport_add - add vport device (for kernel callers)
+ *
+ * @parms: Information about new vport.
+ *
+ * Creates a new vport with the specified configuration (which is dependent on
+ * device type).  ovs_mutex must be held.
+ */
+struct vport *ovs_vport_add(const struct vport_parms *parms)
+{
+	struct vport_ops *ops;
+	struct vport *vport;
+
+	ops = ovs_vport_lookup(parms);
+	if (ops) {
+		struct hlist_head *bucket;
+
+		vport = ops->create(parms);
+		if (IS_ERR(vport))
+			return vport;
+
+		bucket = hash_bucket(ovs_dp_get_net(vport->dp),
+				     ovs_vport_name(vport));
+		hlist_add_head_rcu(&vport->hash_node, bucket);
+		return vport;
+	}
+
+	return ERR_PTR(-EAFNOSUPPORT);
+}
+
+/**
+ *	ovs_vport_del - delete existing vport device
+ *
+ * @vport: vport to delete.
+ *
+ * Detaches @vport from its datapath and destroys it.  ovs_mutex must
+ * be held.
+ */
+void ovs_vport_del(struct vport *vport)
+{
+	hlist_del_rcu(&vport->hash_node);
+	vport->ops->destroy(vport);
+}
+
+/**
+ *	ovs_vport_get_stats - retrieve device stats
+ *
+ * @vport: vport from which to retrieve the stats
+ * @stats: location to store stats
+ *
+ * Retrieves transmit, receive, and error stats for the given device.
+ *
+ * Must be called with ovs_mutex or rcu_read_lock.
+ */
+void ovs_vport_get_stats(struct vport *vport, struct ovs_vport_stats *stats)
+{
+	const struct rtnl_link_stats64 *dev_stats;
+	struct rtnl_link_stats64 temp;
+
+	dev_stats = dev_get_stats(vport->dev, &temp);
+	stats->rx_errors  = dev_stats->rx_errors;
+	stats->tx_errors  = dev_stats->tx_errors;
+	stats->tx_dropped = dev_stats->tx_dropped;
+	stats->rx_dropped = dev_stats->rx_dropped;
+
+	stats->rx_bytes	  = dev_stats->rx_bytes;
+	stats->rx_packets = dev_stats->rx_packets;
+	stats->tx_bytes	  = dev_stats->tx_bytes;
+	stats->tx_packets = dev_stats->tx_packets;
+}
+
+/**
+ *	ovs_vport_get_upcall_stats - retrieve upcall stats
+ *
+ * @vport: vport from which to retrieve the stats.
+ * @skb: sk_buff where upcall stats should be appended.
+ *
+ * Retrieves upcall stats for the given device.
+ *
+ * Must be called with ovs_mutex or rcu_read_lock.
+ */
+int ovs_vport_get_upcall_stats(struct vport *vport, struct sk_buff *skb)
+{
+	u64 tx_success = 0, tx_fail = 0;
+	struct nlattr *nla;
+	int i;
+
+	for_each_possible_cpu(i) {
+		const struct vport_upcall_stats_percpu *stats;
+		u64 n_success, n_fail;
+		unsigned int start;
+
+		stats = per_cpu_ptr(vport->upcall_stats, i);
+		do {
+			start = u64_stats_fetch_begin(&stats->syncp);
+			n_success = u64_stats_read(&stats->n_success);
+			n_fail = u64_stats_read(&stats->n_fail);
+		} while (u64_stats_fetch_retry(&stats->syncp, start));
+		tx_success += n_success;
+		tx_fail += n_fail;
+	}
+
+	nla = nla_nest_start_noflag(skb, OVS_VPORT_ATTR_UPCALL_STATS);
+	if (!nla)
+		return -EMSGSIZE;
+
+	if (nla_put_u64_64bit(skb, OVS_VPORT_UPCALL_ATTR_SUCCESS, tx_success,
+			      OVS_VPORT_ATTR_PAD)) {
+		nla_nest_cancel(skb, nla);
+		return -EMSGSIZE;
+	}
+
+	if (nla_put_u64_64bit(skb, OVS_VPORT_UPCALL_ATTR_FAIL, tx_fail,
+			      OVS_VPORT_ATTR_PAD)) {
+		nla_nest_cancel(skb, nla);
+		return -EMSGSIZE;
+	}
+	nla_nest_end(skb, nla);
+
+	return 0;
+}
+
+/**
+ *	ovs_vport_set_upcall_portids - set upcall portids of @vport.
+ *
+ * @vport: vport to modify.
+ * @ids: new configuration, an array of port ids.
+ *
+ * Sets the vport's upcall_portids to @ids.
+ *
+ * Returns 0 if successful, -EINVAL if @ids is zero length or cannot be parsed
+ * as an array of U32.
+ *
+ * Must be called with ovs_mutex.
+ */
+int ovs_vport_set_upcall_portids(struct vport *vport, const struct nlattr *ids)
+{
+	struct vport_portids *old, *vport_portids;
+
+	if (!nla_len(ids) || nla_len(ids) % sizeof(u32))
+		return -EINVAL;
+
+	if (nla_len(ids) / sizeof(u32) > nr_cpu_ids)
+		return -EINVAL;
+
+	old = ovsl_dereference(vport->upcall_portids);
+
+	vport_portids = kmalloc(sizeof(*vport_portids) + nla_len(ids),
+				GFP_KERNEL);
+	if (!vport_portids)
+		return -ENOMEM;
+
+	vport_portids->n_ids = nla_len(ids) / sizeof(u32);
+	vport_portids->rn_ids = reciprocal_value(vport_portids->n_ids);
+	nla_memcpy(vport_portids->ids, ids, nla_len(ids));
+
+	rcu_assign_pointer(vport->upcall_portids, vport_portids);
+
+	if (old)
+		kfree_rcu(old, rcu);
+	return 0;
+}
+
+/**
+ *	ovs_vport_get_upcall_portids - get the upcall_portids of @vport.
+ *
+ * @vport: vport from which to retrieve the portids.
+ * @skb: sk_buff where portids should be appended.
+ *
+ * Retrieves the configuration of the given vport, appending the
+ * %OVS_VPORT_ATTR_UPCALL_PID attribute which is the array of upcall
+ * portids to @skb.
+ *
+ * Returns 0 if successful, -EMSGSIZE if @skb has insufficient room.
+ * If an error occurs, @skb is left unmodified.  Must be called with
+ * ovs_mutex or rcu_read_lock.
+ */
+int ovs_vport_get_upcall_portids(const struct vport *vport,
+				 struct sk_buff *skb)
+{
+	struct vport_portids *ids;
+
+	ids = rcu_dereference_ovsl(vport->upcall_portids);
+
+	if (vport->dp->user_features & OVS_DP_F_VPORT_PIDS)
+		return nla_put(skb, OVS_VPORT_ATTR_UPCALL_PID,
+			       ids->n_ids * sizeof(u32), (void *)ids->ids);
+	else
+		return nla_put_u32(skb, OVS_VPORT_ATTR_UPCALL_PID, ids->ids[0]);
+}
+
+/**
+ *	ovs_vport_find_upcall_portid - find the upcall portid to send upcall.
+ *
+ * @vport: vport from which the missed packet is received.
+ * @skb: skb that the missed packet was received.
+ *
+ * Uses the skb_get_hash() to select the upcall portid to send the
+ * upcall.
+ *
+ * Returns the portid of the target socket.  Must be called with rcu_read_lock.
+ */
+u32 ovs_vport_find_upcall_portid(const struct vport *vport,
+				 struct sk_buff *skb)
+{
+	struct vport_portids *ids;
+	u32 ids_index;
+	u32 hash;
+
+	ids = rcu_dereference(vport->upcall_portids);
+
+	/* If there is only one portid, select it in the fast-path. */
+	if (ids->n_ids == 1)
+		return ids->ids[0];
+
+	hash = skb_get_hash(skb);
+	ids_index = hash - ids->n_ids * reciprocal_divide(hash, ids->rn_ids);
+	return ids->ids[ids_index];
+}
+
+/**
+ *	ovs_vport_receive - pass up received packet to the datapath for processing
+ *
+ * @vport: vport that received the packet
+ * @skb: skb that was received
+ * @tun_info: tunnel (if any) that carried packet
+ *
+ * Must be called with rcu_read_lock.  The packet cannot be shared and
+ * skb->data should point to the Ethernet header.
+ */
+int ovs_vport_receive(struct vport *vport, struct sk_buff *skb,
+		      const struct ip_tunnel_info *tun_info)
+{
+	struct sw_flow_key key;
+	int error;
+
+	OVS_CB(skb)->input_vport = vport;
+	OVS_CB(skb)->mru = 0;
+	OVS_CB(skb)->cutlen = U32_MAX;
+	OVS_CB(skb)->probability = 0;
+	OVS_CB(skb)->upcall_pid = 0;
+	if (unlikely(dev_net(skb->dev) != ovs_dp_get_net(vport->dp))) {
+		u32 mark;
+
+		mark = skb->mark;
+		skb_scrub_packet(skb, true);
+		skb->mark = mark;
+		tun_info = NULL;
+	}
+
+	/* Extract flow from 'skb' into 'key'. */
+	error = ovs_flow_key_extract(tun_info, skb, &key);
+	if (unlikely(error)) {
+		kfree_skb(skb);
+		return error;
+	}
+	ovs_dp_process_packet(skb, &key);
+	return 0;
+}
+
+static int packet_length(const struct sk_buff *skb,
+			 struct net_device *dev)
+{
+	int length = skb->len - dev->hard_header_len;
+
+	if (!skb_vlan_tag_present(skb) &&
+	    eth_type_vlan(skb->protocol))
+		length -= VLAN_HLEN;
+
+	/* Don't subtract for multiple VLAN tags. Most (all?) drivers allow
+	 * (ETH_LEN + VLAN_HLEN) in addition to the mtu value, but almost none
+	 * account for 802.1ad. e.g. is_skb_forwardable().
+	 */
+
+	return length > 0 ? length : 0;
+}
+
+void ovs_vport_send(struct vport *vport, struct sk_buff *skb, u8 mac_proto)
+{
+	int mtu = vport->dev->mtu;
+
+	switch (vport->dev->type) {
+	case ARPHRD_NONE:
+		if (mac_proto == MAC_PROTO_ETHERNET) {
+			skb_reset_network_header(skb);
+			skb_reset_mac_len(skb);
+			skb->protocol = htons(ETH_P_TEB);
+		} else if (mac_proto != MAC_PROTO_NONE) {
+			WARN_ON_ONCE(1);
+			goto drop;
+		}
+		break;
+	case ARPHRD_ETHER:
+		if (mac_proto != MAC_PROTO_ETHERNET)
+			goto drop;
+		break;
+	default:
+		goto drop;
+	}
+
+	if (unlikely(packet_length(skb, vport->dev) > mtu &&
+		     !skb_is_gso(skb))) {
+		vport->dev->stats.tx_errors++;
+		if (vport->dev->flags & IFF_UP)
+			net_warn_ratelimited("%s: dropped over-mtu packet: "
+					     "%d > %d\n", vport->dev->name,
+					     packet_length(skb, vport->dev),
+					     mtu);
+		goto drop;
+	}
+
+	skb->dev = vport->dev;
+	skb_clear_tstamp(skb);
+	vport->ops->send(skb);
+	return;
+
+drop:
+	kfree_skb(skb);
+}