Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 264 insertions, 0 deletions

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
new file mode 100644
index 000000000..2bff41aac
--- /dev/null
+++ b/include/net/rtnetlink.h
@@ -0,0 +1,264 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __NET_RTNETLINK_H
+#define __NET_RTNETLINK_H
+
+#include <linux/rtnetlink.h>
+#include <linux/srcu.h>
+#include <net/netlink.h>
+
+typedef int (*rtnl_doit_func)(struct sk_buff *, struct nlmsghdr *,
+			      struct netlink_ext_ack *);
+typedef int (*rtnl_dumpit_func)(struct sk_buff *, struct netlink_callback *);
+
+enum rtnl_link_flags {
+	RTNL_FLAG_DOIT_UNLOCKED		= BIT(0),
+#define RTNL_FLAG_DOIT_PERNET		RTNL_FLAG_DOIT_UNLOCKED
+#define RTNL_FLAG_DOIT_PERNET_WIP	RTNL_FLAG_DOIT_UNLOCKED
+	RTNL_FLAG_BULK_DEL_SUPPORTED	= BIT(1),
+	RTNL_FLAG_DUMP_UNLOCKED		= BIT(2),
+	RTNL_FLAG_DUMP_SPLIT_NLM_DONE	= BIT(3),	/* legacy behavior */
+};
+
+enum rtnl_kinds {
+	RTNL_KIND_NEW,
+	RTNL_KIND_DEL,
+	RTNL_KIND_GET,
+	RTNL_KIND_SET
+};
+#define RTNL_KIND_MASK 0x3
+
+static inline enum rtnl_kinds rtnl_msgtype_kind(int msgtype)
+{
+	return msgtype & RTNL_KIND_MASK;
+}
+
+/**
+ *	struct rtnl_msg_handler - rtnetlink message type and handlers
+ *
+ *	@owner: NULL for built-in, THIS_MODULE for module
+ *	@protocol: Protocol family or PF_UNSPEC
+ *	@msgtype: rtnetlink message type
+ *	@doit: Function pointer called for each request message
+ *	@dumpit: Function pointer called for each dump request (NLM_F_DUMP) message
+ *	@flags: rtnl_link_flags to modify behaviour of doit/dumpit functions
+ */
+struct rtnl_msg_handler {
+	struct module *owner;
+	int protocol;
+	int msgtype;
+	rtnl_doit_func doit;
+	rtnl_dumpit_func dumpit;
+	int flags;
+};
+
+void rtnl_unregister_all(int protocol);
+
+int __rtnl_register_many(const struct rtnl_msg_handler *handlers, int n);
+void __rtnl_unregister_many(const struct rtnl_msg_handler *handlers, int n);
+
+#define rtnl_register_many(handlers)				\
+	__rtnl_register_many(handlers, ARRAY_SIZE(handlers))
+#define rtnl_unregister_many(handlers)				\
+	__rtnl_unregister_many(handlers, ARRAY_SIZE(handlers))
+
+static inline int rtnl_msg_family(const struct nlmsghdr *nlh)
+{
+	if (nlmsg_len(nlh) >= sizeof(struct rtgenmsg))
+		return ((struct rtgenmsg *) nlmsg_data(nlh))->rtgen_family;
+	else
+		return AF_UNSPEC;
+}
+
+/**
+ * struct rtnl_newlink_params - parameters of rtnl_link_ops::newlink()
+ *
+ * @src_net: Source netns of rtnetlink socket
+ * @link_net: Link netns by IFLA_LINK_NETNSID, NULL if not specified
+ * @peer_net: Peer netns
+ * @tb: IFLA_* attributes
+ * @data: IFLA_INFO_DATA attributes
+ */
+struct rtnl_newlink_params {
+	struct net *src_net;
+	struct net *link_net;
+	struct net *peer_net;
+	struct nlattr **tb;
+	struct nlattr **data;
+};
+
+/* Get effective link netns from newlink params. Generally, this is link_net
+ * and falls back to src_net. But for compatibility, a driver may * choose to
+ * use dev_net(dev) instead.
+ */
+static inline struct net *rtnl_newlink_link_net(struct rtnl_newlink_params *p)
+{
+	return p->link_net ? : p->src_net;
+}
+
+/* Get peer netns from newlink params. Fallback to link netns if peer netns is
+ * not specified explicitly.
+ */
+static inline struct net *rtnl_newlink_peer_net(struct rtnl_newlink_params *p)
+{
+	return p->peer_net ? : rtnl_newlink_link_net(p);
+}
+
+/**
+ *	struct rtnl_link_ops - rtnetlink link operations
+ *
+ *	@list: Used internally, protected by link_ops_mutex and SRCU
+ *	@srcu: Used internally
+ *	@kind: Identifier
+ *	@netns_refund: Physical device, move to init_net on netns exit
+ *	@peer_type: Peer device specific netlink attribute number (e.g. VETH_INFO_PEER)
+ *	@maxtype: Highest device specific netlink attribute number
+ *	@policy: Netlink policy for device specific attribute validation
+ *	@validate: Optional validation function for netlink/changelink parameters
+ *	@alloc: netdev allocation function, can be %NULL and is then used
+ *		in place of alloc_netdev_mqs(), in this case @priv_size
+ *		and @setup are unused. Returns a netdev or ERR_PTR().
+ *	@priv_size: sizeof net_device private space
+ *	@setup: net_device setup function
+ *	@newlink: Function for configuring and registering a new device
+ *	@changelink: Function for changing parameters of an existing device
+ *	@dellink: Function to remove a device
+ *	@get_size: Function to calculate required room for dumping device
+ *		   specific netlink attributes
+ *	@fill_info: Function to dump device specific netlink attributes
+ *	@get_xstats_size: Function to calculate required room for dumping device
+ *			  specific statistics
+ *	@fill_xstats: Function to dump device specific statistics
+ *	@get_num_tx_queues: Function to determine number of transmit queues
+ *			    to create when creating a new device.
+ *	@get_num_rx_queues: Function to determine number of receive queues
+ *			    to create when creating a new device.
+ *	@get_link_net: Function to get the i/o netns of the device
+ *	@get_linkxstats_size: Function to calculate the required room for
+ *			      dumping device-specific extended link stats
+ *	@fill_linkxstats: Function to dump device-specific extended link stats
+ */
+struct rtnl_link_ops {
+	struct list_head	list;
+	struct srcu_struct	srcu;
+
+	const char		*kind;
+
+	size_t			priv_size;
+	struct net_device	*(*alloc)(struct nlattr *tb[],
+					  const char *ifname,
+					  unsigned char name_assign_type,
+					  unsigned int num_tx_queues,
+					  unsigned int num_rx_queues);
+	void			(*setup)(struct net_device *dev);
+
+	bool			netns_refund;
+	const u16		peer_type;
+	unsigned int		maxtype;
+	const struct nla_policy	*policy;
+	int			(*validate)(struct nlattr *tb[],
+					    struct nlattr *data[],
+					    struct netlink_ext_ack *extack);
+
+	int			(*newlink)(struct net_device *dev,
+					   struct rtnl_newlink_params *params,
+					   struct netlink_ext_ack *extack);
+	int			(*changelink)(struct net_device *dev,
+					      struct nlattr *tb[],
+					      struct nlattr *data[],
+					      struct netlink_ext_ack *extack);
+	void			(*dellink)(struct net_device *dev,
+					   struct list_head *head);
+
+	size_t			(*get_size)(const struct net_device *dev);
+	int			(*fill_info)(struct sk_buff *skb,
+					     const struct net_device *dev);
+
+	size_t			(*get_xstats_size)(const struct net_device *dev);
+	int			(*fill_xstats)(struct sk_buff *skb,
+					       const struct net_device *dev);
+	unsigned int		(*get_num_tx_queues)(void);
+	unsigned int		(*get_num_rx_queues)(void);
+
+	unsigned int		slave_maxtype;
+	const struct nla_policy	*slave_policy;
+	int			(*slave_changelink)(struct net_device *dev,
+						    struct net_device *slave_dev,
+						    struct nlattr *tb[],
+						    struct nlattr *data[],
+						    struct netlink_ext_ack *extack);
+	size_t			(*get_slave_size)(const struct net_device *dev,
+						  const struct net_device *slave_dev);
+	int			(*fill_slave_info)(struct sk_buff *skb,
+						   const struct net_device *dev,
+						   const struct net_device *slave_dev);
+	struct net		*(*get_link_net)(const struct net_device *dev);
+	size_t			(*get_linkxstats_size)(const struct net_device *dev,
+						       int attr);
+	int			(*fill_linkxstats)(struct sk_buff *skb,
+						   const struct net_device *dev,
+						   int *prividx, int attr);
+};
+
+int rtnl_link_register(struct rtnl_link_ops *ops);
+void rtnl_link_unregister(struct rtnl_link_ops *ops);
+
+/**
+ * 	struct rtnl_af_ops - rtnetlink address family operations
+ *
+ *	@list: Used internally, protected by RTNL and SRCU
+ *	@srcu: Used internally
+ * 	@family: Address family
+ * 	@fill_link_af: Function to fill IFLA_AF_SPEC with address family
+ * 		       specific netlink attributes.
+ * 	@get_link_af_size: Function to calculate size of address family specific
+ * 			   netlink attributes.
+ *	@validate_link_af: Validate a IFLA_AF_SPEC attribute, must check attr
+ *			   for invalid configuration settings.
+ * 	@set_link_af: Function to parse a IFLA_AF_SPEC attribute and modify
+ *		      net_device accordingly.
+ */
+struct rtnl_af_ops {
+	struct list_head	list;
+	struct srcu_struct	srcu;
+
+	int			family;
+
+	int			(*fill_link_af)(struct sk_buff *skb,
+						const struct net_device *dev,
+						u32 ext_filter_mask);
+	size_t			(*get_link_af_size)(const struct net_device *dev,
+						    u32 ext_filter_mask);
+
+	int			(*validate_link_af)(const struct net_device *dev,
+						    const struct nlattr *attr,
+						    struct netlink_ext_ack *extack);
+	int			(*set_link_af)(struct net_device *dev,
+					       const struct nlattr *attr,
+					       struct netlink_ext_ack *extack);
+	int			(*fill_stats_af)(struct sk_buff *skb,
+						 const struct net_device *dev);
+	size_t			(*get_stats_af_size)(const struct net_device *dev);
+};
+
+int rtnl_af_register(struct rtnl_af_ops *ops);
+void rtnl_af_unregister(struct rtnl_af_ops *ops);
+
+struct net *rtnl_link_get_net(struct net *src_net, struct nlattr *tb[]);
+struct net_device *rtnl_create_link(struct net *net, const char *ifname,
+				    unsigned char name_assign_type,
+				    const struct rtnl_link_ops *ops,
+				    struct nlattr *tb[],
+				    struct netlink_ext_ack *extack);
+int rtnl_delete_link(struct net_device *dev, u32 portid, const struct nlmsghdr *nlh);
+int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm,
+			u32 portid, const struct nlmsghdr *nlh);
+
+int rtnl_nla_parse_ifinfomsg(struct nlattr **tb, const struct nlattr *nla_peer,
+			     struct netlink_ext_ack *exterr);
+struct net *rtnl_get_net_ns_capable(struct sock *sk, int netnsid);
+bool rtnl_dev_link_net_capable(const struct net_device *dev,
+			       const struct net *link_net);
+
+#define MODULE_ALIAS_RTNL_LINK(kind) MODULE_ALIAS("rtnl-link-" kind)
+
+#endif