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, 432 insertions, 0 deletions

diff --git a/include/net/route.h b/include/net/route.h
new file mode 100644
index 000000000..45290177a
--- /dev/null
+++ b/include/net/route.h
@@ -0,0 +1,432 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * INET		An implementation of the TCP/IP protocol suite for the LINUX
+ *		operating system.  INET  is implemented using the  BSD Socket
+ *		interface as the means of communication with the user level.
+ *
+ *		Definitions for the IP router.
+ *
+ * Version:	@(#)route.h	1.0.4	05/27/93
+ *
+ * Authors:	Ross Biro
+ *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Fixes:
+ *		Alan Cox	:	Reformatted. Added ip_rt_local()
+ *		Alan Cox	:	Support for TCP parameters.
+ *		Alexey Kuznetsov:	Major changes for new routing code.
+ *		Mike McLagan    :	Routing by source
+ *		Robert Olsson   :	Added rt_cache statistics
+ */
+#ifndef _ROUTE_H
+#define _ROUTE_H
+
+#include <net/dst.h>
+#include <net/inetpeer.h>
+#include <net/flow.h>
+#include <net/inet_sock.h>
+#include <net/ip_fib.h>
+#include <net/arp.h>
+#include <net/ndisc.h>
+#include <net/inet_dscp.h>
+#include <net/sock.h>
+#include <linux/in_route.h>
+#include <linux/rtnetlink.h>
+#include <linux/rcupdate.h>
+#include <linux/route.h>
+#include <linux/ip.h>
+#include <linux/cache.h>
+#include <linux/security.h>
+
+static inline __u8 ip_sock_rt_scope(const struct sock *sk)
+{
+	if (sock_flag(sk, SOCK_LOCALROUTE))
+		return RT_SCOPE_LINK;
+
+	return RT_SCOPE_UNIVERSE;
+}
+
+static inline __u8 ip_sock_rt_tos(const struct sock *sk)
+{
+	return READ_ONCE(inet_sk(sk)->tos) & INET_DSCP_MASK;
+}
+
+struct ip_tunnel_info;
+struct fib_nh;
+struct fib_info;
+struct uncached_list;
+struct rtable {
+	struct dst_entry	dst;
+
+	int			rt_genid;
+	unsigned int		rt_flags;
+	__u16			rt_type;
+	__u8			rt_is_input;
+	__u8			rt_uses_gateway;
+
+	int			rt_iif;
+
+	u8			rt_gw_family;
+	/* Info on neighbour */
+	union {
+		__be32		rt_gw4;
+		struct in6_addr	rt_gw6;
+	};
+
+	/* Miscellaneous cached information */
+	u32			rt_mtu_locked:1,
+				rt_pmtu:31;
+};
+
+#define dst_rtable(_ptr) container_of_const(_ptr, struct rtable, dst)
+
+/**
+ * skb_rtable - Returns the skb &rtable
+ * @skb: buffer
+ */
+static inline struct rtable *skb_rtable(const struct sk_buff *skb)
+{
+	return dst_rtable(skb_dst(skb));
+}
+
+static inline bool rt_is_input_route(const struct rtable *rt)
+{
+	return rt->rt_is_input != 0;
+}
+
+static inline bool rt_is_output_route(const struct rtable *rt)
+{
+	return rt->rt_is_input == 0;
+}
+
+static inline __be32 rt_nexthop(const struct rtable *rt, __be32 daddr)
+{
+	if (rt->rt_gw_family == AF_INET)
+		return rt->rt_gw4;
+	return daddr;
+}
+
+struct ip_rt_acct {
+	__u32 	o_bytes;
+	__u32 	o_packets;
+	__u32 	i_bytes;
+	__u32 	i_packets;
+};
+
+struct rt_cache_stat {
+        unsigned int in_slow_tot;
+        unsigned int in_slow_mc;
+        unsigned int in_no_route;
+        unsigned int in_brd;
+        unsigned int in_martian_dst;
+        unsigned int in_martian_src;
+        unsigned int out_slow_tot;
+        unsigned int out_slow_mc;
+};
+
+extern struct ip_rt_acct __percpu *ip_rt_acct;
+
+struct in_device;
+
+int ip_rt_init(void);
+void rt_cache_flush(struct net *net);
+void rt_flush_dev(struct net_device *dev);
+
+static inline void inet_sk_init_flowi4(const struct inet_sock *inet,
+				       struct flowi4 *fl4)
+{
+	const struct ip_options_rcu *ip4_opt;
+	const struct sock *sk;
+	__be32 daddr;
+
+	rcu_read_lock();
+	ip4_opt = rcu_dereference(inet->inet_opt);
+
+	/* Source routing option overrides the socket destination address */
+	if (ip4_opt && ip4_opt->opt.srr)
+		daddr = ip4_opt->opt.faddr;
+	else
+		daddr = inet->inet_daddr;
+	rcu_read_unlock();
+
+	sk = &inet->sk;
+	flowi4_init_output(fl4, sk->sk_bound_dev_if, READ_ONCE(sk->sk_mark),
+			   ip_sock_rt_tos(sk), ip_sock_rt_scope(sk),
+			   sk->sk_protocol, inet_sk_flowi_flags(sk), daddr,
+			   inet->inet_saddr, inet->inet_dport,
+			   inet->inet_sport, sk_uid(sk));
+	security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
+}
+
+struct rtable *ip_route_output_key_hash(struct net *net, struct flowi4 *flp,
+					const struct sk_buff *skb);
+struct rtable *ip_route_output_key_hash_rcu(struct net *net, struct flowi4 *flp,
+					    struct fib_result *res,
+					    const struct sk_buff *skb);
+
+static inline struct rtable *__ip_route_output_key(struct net *net,
+						   struct flowi4 *flp)
+{
+	return ip_route_output_key_hash(net, flp, NULL);
+}
+
+struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
+				    const struct sock *sk);
+struct dst_entry *ipv4_blackhole_route(struct net *net,
+				       struct dst_entry *dst_orig);
+
+static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 *flp)
+{
+	return ip_route_output_flow(net, flp, NULL);
+}
+
+/* Simplistic IPv4 route lookup function.
+ * This is only suitable for some particular use cases: since the flowi4
+ * structure is only partially set, it may bypass some fib-rules.
+ */
+static inline struct rtable *ip_route_output(struct net *net, __be32 daddr,
+					     __be32 saddr, dscp_t dscp,
+					     int oif, __u8 scope)
+{
+	struct flowi4 fl4 = {
+		.flowi4_oif = oif,
+		.flowi4_dscp = dscp,
+		.flowi4_scope = scope,
+		.daddr = daddr,
+		.saddr = saddr,
+	};
+
+	return ip_route_output_key(net, &fl4);
+}
+
+static inline struct rtable *ip_route_output_ports(struct net *net, struct flowi4 *fl4,
+						   const struct sock *sk,
+						   __be32 daddr, __be32 saddr,
+						   __be16 dport, __be16 sport,
+						   __u8 proto, __u8 tos, int oif)
+{
+	flowi4_init_output(fl4, oif, sk ? READ_ONCE(sk->sk_mark) : 0, tos,
+			   sk ? ip_sock_rt_scope(sk) : RT_SCOPE_UNIVERSE,
+			   proto, sk ? inet_sk_flowi_flags(sk) : 0,
+			   daddr, saddr, dport, sport, sock_net_uid(net, sk));
+	if (sk)
+		security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
+	return ip_route_output_flow(net, fl4, sk);
+}
+
+enum skb_drop_reason
+ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+		      dscp_t dscp, struct net_device *dev,
+		      struct in_device *in_dev, u32 *itag);
+enum skb_drop_reason
+ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+		     dscp_t dscp, struct net_device *dev);
+enum skb_drop_reason
+ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+		  dscp_t dscp, struct net_device *dev,
+		  const struct sk_buff *hint);
+
+static inline enum skb_drop_reason
+ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, dscp_t dscp,
+	       struct net_device *devin)
+{
+	enum skb_drop_reason reason;
+
+	rcu_read_lock();
+	reason = ip_route_input_noref(skb, dst, src, dscp, devin);
+	if (!reason) {
+		skb_dst_force(skb);
+		if (!skb_dst(skb))
+			reason = SKB_DROP_REASON_NOT_SPECIFIED;
+	}
+	rcu_read_unlock();
+
+	return reason;
+}
+
+void ipv4_update_pmtu(struct sk_buff *skb, struct net *net, u32 mtu, int oif,
+		      u8 protocol);
+void ipv4_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, u32 mtu);
+void ipv4_redirect(struct sk_buff *skb, struct net *net, int oif, u8 protocol);
+void ipv4_sk_redirect(struct sk_buff *skb, struct sock *sk);
+void ip_rt_send_redirect(struct sk_buff *skb);
+
+unsigned int inet_addr_type(struct net *net, __be32 addr);
+unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id);
+unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev,
+				__be32 addr);
+unsigned int inet_addr_type_dev_table(struct net *net,
+				      const struct net_device *dev,
+				      __be32 addr);
+void ip_rt_multicast_event(struct in_device *);
+int ip_rt_ioctl(struct net *, unsigned int cmd, struct rtentry *rt);
+void ip_rt_get_source(u8 *src, struct sk_buff *skb, struct rtable *rt);
+struct rtable *rt_dst_alloc(struct net_device *dev,
+			    unsigned int flags, u16 type, bool noxfrm);
+struct rtable *rt_dst_clone(struct net_device *dev, struct rtable *rt);
+
+struct in_ifaddr;
+void fib_add_ifaddr(struct in_ifaddr *);
+void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *);
+void fib_modify_prefix_metric(struct in_ifaddr *ifa, u32 new_metric);
+
+void rt_add_uncached_list(struct rtable *rt);
+void rt_del_uncached_list(struct rtable *rt);
+
+int fib_dump_info_fnhe(struct sk_buff *skb, struct netlink_callback *cb,
+		       u32 table_id, struct fib_info *fi,
+		       int *fa_index, int fa_start, unsigned int flags);
+
+void fnhe_update_pmtu(struct fib_nh_exception *fnhe, u32 new, u32 orig);
+
+static inline void ip_rt_put(struct rtable *rt)
+{
+	/* dst_release() accepts a NULL parameter.
+	 * We rely on dst being first structure in struct rtable
+	 */
+	BUILD_BUG_ON(offsetof(struct rtable, dst) != 0);
+	dst_release(&rt->dst);
+}
+
+extern const __u8 ip_tos2prio[16];
+
+static inline char rt_tos2priority(u8 tos)
+{
+	return ip_tos2prio[IPTOS_TOS(tos)>>1];
+}
+
+/* ip_route_connect() and ip_route_newports() work in tandem whilst
+ * binding a socket for a new outgoing connection.
+ *
+ * In order to use IPSEC properly, we must, in the end, have a
+ * route that was looked up using all available keys including source
+ * and destination ports.
+ *
+ * However, if a source port needs to be allocated (the user specified
+ * a wildcard source port) we need to obtain addressing information
+ * in order to perform that allocation.
+ *
+ * So ip_route_connect() looks up a route using wildcarded source and
+ * destination ports in the key, simply so that we can get a pair of
+ * addresses to use for port allocation.
+ *
+ * Later, once the ports are allocated, ip_route_newports() will make
+ * another route lookup if needed to make sure we catch any IPSEC
+ * rules keyed on the port information.
+ *
+ * The callers allocate the flow key on their stack, and must pass in
+ * the same flowi4 object to both the ip_route_connect() and the
+ * ip_route_newports() calls.
+ */
+
+static inline void ip_route_connect_init(struct flowi4 *fl4, __be32 dst,
+					 __be32 src, int oif, u8 protocol,
+					 __be16 sport, __be16 dport,
+					 const struct sock *sk)
+{
+	__u8 flow_flags = 0;
+
+	if (inet_test_bit(TRANSPARENT, sk))
+		flow_flags |= FLOWI_FLAG_ANYSRC;
+
+	if (IS_ENABLED(CONFIG_IP_ROUTE_MULTIPATH) && !sport)
+		flow_flags |= FLOWI_FLAG_ANY_SPORT;
+
+	flowi4_init_output(fl4, oif, READ_ONCE(sk->sk_mark), ip_sock_rt_tos(sk),
+			   ip_sock_rt_scope(sk), protocol, flow_flags, dst,
+			   src, dport, sport, sk_uid(sk));
+}
+
+static inline struct rtable *ip_route_connect(struct flowi4 *fl4, __be32 dst,
+					      __be32 src, int oif, u8 protocol,
+					      __be16 sport, __be16 dport,
+					      const struct sock *sk)
+{
+	struct net *net = sock_net(sk);
+	struct rtable *rt;
+
+	ip_route_connect_init(fl4, dst, src, oif, protocol, sport, dport, sk);
+
+	if (!dst || !src) {
+		rt = __ip_route_output_key(net, fl4);
+		if (IS_ERR(rt))
+			return rt;
+		ip_rt_put(rt);
+		flowi4_update_output(fl4, oif, fl4->daddr, fl4->saddr);
+	}
+	security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
+	return ip_route_output_flow(net, fl4, sk);
+}
+
+static inline struct rtable *ip_route_newports(struct flowi4 *fl4, struct rtable *rt,
+					       __be16 orig_sport, __be16 orig_dport,
+					       __be16 sport, __be16 dport,
+					       const struct sock *sk)
+{
+	if (sport != orig_sport || dport != orig_dport) {
+		fl4->fl4_dport = dport;
+		fl4->fl4_sport = sport;
+		ip_rt_put(rt);
+		flowi4_update_output(fl4, sk->sk_bound_dev_if, fl4->daddr,
+				     fl4->saddr);
+		security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
+		return ip_route_output_flow(sock_net(sk), fl4, sk);
+	}
+	return rt;
+}
+
+static inline int inet_iif(const struct sk_buff *skb)
+{
+	struct rtable *rt = skb_rtable(skb);
+
+	if (rt && rt->rt_iif)
+		return rt->rt_iif;
+
+	return skb->skb_iif;
+}
+
+static inline int ip4_dst_hoplimit(const struct dst_entry *dst)
+{
+	int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
+
+	if (hoplimit == 0) {
+		const struct net *net;
+
+		rcu_read_lock();
+		net = dst_dev_net_rcu(dst);
+		hoplimit = READ_ONCE(net->ipv4.sysctl_ip_default_ttl);
+		rcu_read_unlock();
+	}
+	return hoplimit;
+}
+
+static inline struct neighbour *ip_neigh_gw4(struct net_device *dev,
+					     __be32 daddr)
+{
+	struct neighbour *neigh;
+
+	neigh = __ipv4_neigh_lookup_noref(dev, (__force u32)daddr);
+	if (unlikely(!neigh))
+		neigh = __neigh_create(&arp_tbl, &daddr, dev, false);
+
+	return neigh;
+}
+
+static inline struct neighbour *ip_neigh_for_gw(struct rtable *rt,
+						struct sk_buff *skb,
+						bool *is_v6gw)
+{
+	struct net_device *dev = rt->dst.dev;
+	struct neighbour *neigh;
+
+	if (likely(rt->rt_gw_family == AF_INET)) {
+		neigh = ip_neigh_gw4(dev, rt->rt_gw4);
+	} else if (rt->rt_gw_family == AF_INET6) {
+		neigh = ip_neigh_gw6(dev, &rt->rt_gw6);
+		*is_v6gw = true;
+	} else {
+		neigh = ip_neigh_gw4(dev, ip_hdr(skb)->daddr);
+	}
+	return neigh;
+}
+
+#endif	/* _ROUTE_H */