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, 236 insertions, 0 deletions

diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h
new file mode 100644
index 000000000..2058fabff
--- /dev/null
+++ b/include/net/sctp/command.h
@@ -0,0 +1,236 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* SCTP kernel Implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (C) 1999-2001 Cisco, Motorola
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * These are the definitions needed for the command object.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *   La Monte H.P. Yarroll <piggy@acm.org>
+ *   Karl Knutson <karl@athena.chicago.il.us>
+ *   Ardelle Fan <ardelle.fan@intel.com>
+ *   Sridhar Samudrala <sri@us.ibm.com>
+ */
+
+#ifndef __net_sctp_command_h__
+#define __net_sctp_command_h__
+
+#include <net/sctp/constants.h>
+#include <net/sctp/structs.h>
+
+
+enum sctp_verb {
+	SCTP_CMD_NOP = 0,	/* Do nothing. */
+	SCTP_CMD_NEW_ASOC,	/* Register a new association.  */
+	SCTP_CMD_DELETE_TCB,	/* Delete the current association. */
+	SCTP_CMD_NEW_STATE,	/* Enter a new state.  */
+	SCTP_CMD_REPORT_TSN,	/* Record the arrival of a TSN.  */
+	SCTP_CMD_GEN_SACK,	/* Send a Selective ACK (maybe).  */
+	SCTP_CMD_PROCESS_SACK,	/* Process an inbound SACK.  */
+	SCTP_CMD_GEN_INIT_ACK,	/* Generate an INIT ACK chunk.  */
+	SCTP_CMD_PEER_INIT,	/* Process a INIT from the peer.  */
+	SCTP_CMD_GEN_COOKIE_ECHO, /* Generate a COOKIE ECHO chunk. */
+	SCTP_CMD_CHUNK_ULP,	/* Send a chunk to the sockets layer.  */
+	SCTP_CMD_EVENT_ULP,	/* Send a notification to the sockets layer. */
+	SCTP_CMD_REPLY,		/* Send a chunk to our peer.  */
+	SCTP_CMD_SEND_PKT,	/* Send a full packet to our peer.  */
+	SCTP_CMD_RETRAN,	/* Mark a transport for retransmission.  */
+	SCTP_CMD_ECN_CE,        /* Do delayed CE processing.   */
+	SCTP_CMD_ECN_ECNE,	/* Do delayed ECNE processing. */
+	SCTP_CMD_ECN_CWR,	/* Do delayed CWR processing.  */
+	SCTP_CMD_TIMER_START,	/* Start a timer.  */
+	SCTP_CMD_TIMER_START_ONCE, /* Start a timer once */
+	SCTP_CMD_TIMER_RESTART,	/* Restart a timer. */
+	SCTP_CMD_TIMER_STOP,	/* Stop a timer. */
+	SCTP_CMD_INIT_CHOOSE_TRANSPORT, /* Choose transport for an INIT. */
+	SCTP_CMD_INIT_COUNTER_RESET, /* Reset init counter. */
+	SCTP_CMD_INIT_COUNTER_INC,   /* Increment init counter. */
+	SCTP_CMD_INIT_RESTART,  /* High level, do init timer work. */
+	SCTP_CMD_COOKIEECHO_RESTART,  /* High level, do cookie-echo timer work. */
+	SCTP_CMD_INIT_FAILED,   /* High level, do init failure work. */
+	SCTP_CMD_REPORT_DUP,	/* Report a duplicate TSN.  */
+	SCTP_CMD_STRIKE,	/* Mark a strike against a transport.  */
+	SCTP_CMD_HB_TIMERS_START,    /* Start the heartbeat timers. */
+	SCTP_CMD_HB_TIMER_UPDATE,    /* Update a heartbeat timers.  */
+	SCTP_CMD_HB_TIMERS_STOP,     /* Stop the heartbeat timers.  */
+	SCTP_CMD_PROBE_TIMER_UPDATE, /* Update a probe timer.  */
+	SCTP_CMD_TRANSPORT_HB_SENT,  /* Reset the status of a transport. */
+	SCTP_CMD_TRANSPORT_IDLE,     /* Do manipulations on idle transport */
+	SCTP_CMD_TRANSPORT_ON,       /* Mark the transport as active. */
+	SCTP_CMD_REPORT_ERROR,   /* Pass this error back out of the sm. */
+	SCTP_CMD_REPORT_BAD_TAG, /* Verification tags didn't match. */
+	SCTP_CMD_PROCESS_CTSN,   /* Sideeffect from shutdown. */
+	SCTP_CMD_ASSOC_FAILED,	 /* Handle association failure. */
+	SCTP_CMD_DISCARD_PACKET, /* Discard the whole packet. */
+	SCTP_CMD_GEN_SHUTDOWN,   /* Generate a SHUTDOWN chunk. */
+	SCTP_CMD_PURGE_OUTQUEUE, /* Purge all data waiting to be sent. */
+	SCTP_CMD_SETUP_T2,       /* Hi-level, setup T2-shutdown parms.  */
+	SCTP_CMD_RTO_PENDING,	 /* Set transport's rto_pending. */
+	SCTP_CMD_PART_DELIVER,	 /* Partial data delivery considerations. */
+	SCTP_CMD_RENEGE,         /* Renege data on an association. */
+	SCTP_CMD_SETUP_T4,	 /* ADDIP, setup T4 RTO timer parms. */
+	SCTP_CMD_PROCESS_OPERR,  /* Process an ERROR chunk. */
+	SCTP_CMD_REPORT_FWDTSN,	 /* Report new cumulative TSN Ack. */
+	SCTP_CMD_PROCESS_FWDTSN, /* Skips were reported, so process further. */
+	SCTP_CMD_CLEAR_INIT_TAG, /* Clears association peer's inittag. */
+	SCTP_CMD_DEL_NON_PRIMARY, /* Removes non-primary peer transports. */
+	SCTP_CMD_T3_RTX_TIMERS_STOP, /* Stops T3-rtx pending timers */
+	SCTP_CMD_FORCE_PRIM_RETRAN,  /* Forces retrans. over primary path. */
+	SCTP_CMD_SET_SK_ERR,	 /* Set sk_err */
+	SCTP_CMD_ASSOC_CHANGE,	 /* generate and send assoc_change event */
+	SCTP_CMD_ADAPTATION_IND, /* generate and send adaptation event */
+	SCTP_CMD_PEER_NO_AUTH,   /* generate and send authentication event */
+	SCTP_CMD_ASSOC_SHKEY,    /* generate the association shared keys */
+	SCTP_CMD_T1_RETRAN,	 /* Mark for retransmission after T1 timeout  */
+	SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */
+	SCTP_CMD_SEND_MSG,	 /* Send the whole use message */
+	SCTP_CMD_PURGE_ASCONF_QUEUE, /* Purge all asconf queues.*/
+	SCTP_CMD_SET_ASOC,	 /* Restore association context */
+	SCTP_CMD_LAST
+};
+
+/* How many commands can you put in an struct sctp_cmd_seq?
+ * This is a rather arbitrary number, ideally derived from a careful
+ * analysis of the state functions, but in reality just taken from
+ * thin air in the hopes othat we don't trigger a kernel panic.
+ */
+#define SCTP_MAX_NUM_COMMANDS 20
+
+union sctp_arg {
+	void *zero_all;	/* Set to NULL to clear the entire union */
+	__s32 i32;
+	__u32 u32;
+	__be32 be32;
+	__u16 u16;
+	__u8 u8;
+	int error;
+	__be16 err;
+	enum sctp_state state;
+	enum sctp_event_timeout to;
+	struct sctp_chunk *chunk;
+	struct sctp_association *asoc;
+	struct sctp_transport *transport;
+	struct sctp_bind_addr *bp;
+	struct sctp_init_chunk *init;
+	struct sctp_ulpevent *ulpevent;
+	struct sctp_packet *packet;
+	struct sctp_sackhdr *sackh;
+	struct sctp_datamsg *msg;
+};
+
+/* We are simulating ML type constructors here.
+ *
+ * SCTP_ARG_CONSTRUCTOR(NAME, TYPE, ELT) builds a function called
+ * SCTP_NAME() which takes an argument of type TYPE and returns an
+ * union sctp_arg.  It does this by inserting the sole argument into
+ * the ELT union element of a local union sctp_arg.
+ *
+ * E.g., SCTP_ARG_CONSTRUCTOR(I32, __s32, i32) builds SCTP_I32(arg),
+ * which takes an __s32 and returns a union sctp_arg containing the
+ * __s32.  So, after foo = SCTP_I32(arg), foo.i32 == arg.
+ */
+
+#define SCTP_ARG_CONSTRUCTOR(name, type, elt) \
+static inline union sctp_arg	\
+SCTP_## name (type arg)		\
+{ union sctp_arg retval;\
+  retval.zero_all = NULL;\
+  retval.elt = arg;\
+  return retval;\
+}
+
+SCTP_ARG_CONSTRUCTOR(I32,	__s32, i32)
+SCTP_ARG_CONSTRUCTOR(U32,	__u32, u32)
+SCTP_ARG_CONSTRUCTOR(BE32,	__be32, be32)
+SCTP_ARG_CONSTRUCTOR(U16,	__u16, u16)
+SCTP_ARG_CONSTRUCTOR(U8,	__u8, u8)
+SCTP_ARG_CONSTRUCTOR(ERROR,     int, error)
+SCTP_ARG_CONSTRUCTOR(PERR,      __be16, err)	/* protocol error */
+SCTP_ARG_CONSTRUCTOR(STATE,	enum sctp_state, state)
+SCTP_ARG_CONSTRUCTOR(TO,	enum sctp_event_timeout, to)
+SCTP_ARG_CONSTRUCTOR(CHUNK,	struct sctp_chunk *, chunk)
+SCTP_ARG_CONSTRUCTOR(ASOC,	struct sctp_association *, asoc)
+SCTP_ARG_CONSTRUCTOR(TRANSPORT,	struct sctp_transport *, transport)
+SCTP_ARG_CONSTRUCTOR(BA,	struct sctp_bind_addr *, bp)
+SCTP_ARG_CONSTRUCTOR(PEER_INIT,	struct sctp_init_chunk *, init)
+SCTP_ARG_CONSTRUCTOR(ULPEVENT,  struct sctp_ulpevent *, ulpevent)
+SCTP_ARG_CONSTRUCTOR(PACKET,	struct sctp_packet *, packet)
+SCTP_ARG_CONSTRUCTOR(SACKH,	struct sctp_sackhdr *, sackh)
+SCTP_ARG_CONSTRUCTOR(DATAMSG,	struct sctp_datamsg *, msg)
+
+static inline union sctp_arg SCTP_FORCE(void)
+{
+	return SCTP_I32(1);
+}
+
+static inline union sctp_arg SCTP_NOFORCE(void)
+{
+	return SCTP_I32(0);
+}
+
+static inline union sctp_arg SCTP_NULL(void)
+{
+	union sctp_arg retval;
+	retval.zero_all = NULL;
+	return retval;
+}
+
+struct sctp_cmd {
+	union sctp_arg obj;
+	enum sctp_verb verb;
+};
+
+struct sctp_cmd_seq {
+	struct sctp_cmd cmds[SCTP_MAX_NUM_COMMANDS];
+	struct sctp_cmd *last_used_slot;
+	struct sctp_cmd *next_cmd;
+};
+
+
+/* Initialize a block of memory as a command sequence.
+ * Return 0 if the initialization fails.
+ */
+static inline int sctp_init_cmd_seq(struct sctp_cmd_seq *seq)
+{
+	/* cmds[] is filled backwards to simplify the overflow BUG() check */
+	seq->last_used_slot = seq->cmds + SCTP_MAX_NUM_COMMANDS;
+	seq->next_cmd = seq->last_used_slot;
+	return 1;		/* We always succeed.  */
+}
+
+
+/* Add a command to an struct sctp_cmd_seq.
+ *
+ * Use the SCTP_* constructors defined by SCTP_ARG_CONSTRUCTOR() above
+ * to wrap data which goes in the obj argument.
+ */
+static inline void sctp_add_cmd_sf(struct sctp_cmd_seq *seq,
+				   enum sctp_verb verb, union sctp_arg obj)
+{
+	struct sctp_cmd *cmd = seq->last_used_slot - 1;
+
+	BUG_ON(cmd < seq->cmds);
+
+	cmd->verb = verb;
+	cmd->obj = obj;
+	seq->last_used_slot = cmd;
+}
+
+/* Return the next command structure in an sctp_cmd_seq.
+ * Return NULL at the end of the sequence.
+ */
+static inline struct sctp_cmd *sctp_next_cmd(struct sctp_cmd_seq *seq)
+{
+	if (seq->next_cmd <= seq->last_used_slot)
+		return NULL;
+
+	return --seq->next_cmd;
+}
+
+#endif /* __net_sctp_command_h__ */