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, 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__ */