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, 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 */