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, 535 insertions, 0 deletions

diff --git a/Documentation/netlink/netlink-raw.yaml b/Documentation/netlink/netlink-raw.yaml
new file mode 100644
index 000000000..4c436b59a
--- /dev/null
+++ b/Documentation/netlink/netlink-raw.yaml
@@ -0,0 +1,535 @@
+# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+%YAML 1.2
+---
+$id: http://kernel.org/schemas/netlink/netlink-raw.yaml#
+$schema: https://json-schema.org/draft-07/schema
+
+# Common defines
+$defs:
+  name:
+    type: string
+    pattern: ^[0-9a-z-]+$
+  name-cap:
+    type: string
+    pattern: ^[0-9a-zA-Z-]+$
+  uint:
+    type: integer
+    minimum: 0
+  len-or-define:
+    type: [ string, integer ]
+    pattern: ^[0-9A-Za-z_-]+( - 1)?$
+    minimum: 0
+  len-or-limit:
+    # literal int, const name, or limit based on fixed-width type
+    # e.g. u8-min, u16-max, etc.
+    type: [ string, integer ]
+    pattern: ^[0-9A-Za-z_-]+$
+    minimum: 0
+
+# Schema for specs
+title: Protocol
+description: Specification of a raw netlink protocol
+type: object
+required: [ name, doc, attribute-sets, operations ]
+additionalProperties: False
+properties:
+  name:
+    description: Name of the netlink family.
+    type: string
+  doc:
+    type: string
+  protocol:
+    description: Schema compatibility level.
+    enum: [ netlink-raw ] # Trim
+  # Start netlink-raw
+  protonum:
+    description: Protocol number to use for netlink-raw
+    type: integer
+  # End netlink-raw
+  uapi-header:
+    description: Path to the uAPI header, default is linux/${family-name}.h
+    type: string
+  # Start genetlink-c
+  c-family-name:
+    description: Name of the define for the family name.
+    type: string
+  c-version-name:
+    description: Name of the define for the version of the family.
+    type: string
+  max-by-define:
+    description: Makes the number of attributes and commands be specified by a define, not an enum value.
+    type: boolean
+  cmd-max-name:
+    description: Name of the define for the last operation in the list.
+    type: string
+  cmd-cnt-name:
+    description: The explicit name for constant holding the count of operations (last operation + 1).
+    type: string
+  # End genetlink-c
+  # Start genetlink-legacy
+  kernel-policy:
+    description: |
+      Defines if the input policy in the kernel is global, per-operation, or split per operation type.
+      Default is split.
+    enum: [ split, per-op, global ]
+  # End genetlink-legacy
+
+  definitions:
+    description: List of type and constant definitions (enums, flags, defines).
+    type: array
+    items:
+      type: object
+      required: [ type, name ]
+      additionalProperties: False
+      properties:
+        name:
+          $ref: '#/$defs/name'
+        header:
+          description: For C-compatible languages, header which already defines this value.
+          type: string
+        scope:
+          description: |
+            Visibility of this definition. "uapi" (default) renders into
+            the uAPI header, "kernel" renders into the kernel-side
+            generated header, "user" renders into the user-side
+            generated header. When combined with `header:`, the
+            definition is not rendered, and the named header is
+            included only by code matching the scope.
+          enum: [ uapi, kernel, user ]
+        type:
+          enum: [ const, enum, flags, struct ] # Trim
+        doc:
+          type: string
+        # For const
+        value:
+          description: For const - the value.
+          type: [ string, integer ]
+        # For enum and flags
+        value-start:
+          description: For enum or flags the literal initializer for the first value.
+          type: [ string, integer ]
+        entries:
+          description: For enum or flags array of values.
+          type: array
+          items:
+            oneOf:
+              - type: string
+              - type: object
+                required: [ name ]
+                additionalProperties: False
+                properties:
+                  name:
+                    $ref: '#/$defs/name'
+                  value:
+                    type: integer
+                  doc:
+                    type: string
+        render-max:
+          description: Render the max members for this enum.
+          type: boolean
+        # Start genetlink-c
+        enum-name:
+          description: Name for enum, if empty no name will be used.
+          type: [ string, "null" ]
+        name-prefix:
+          description: For enum the prefix of the values, optional.
+          type: string
+        # End genetlink-c
+        # Start genetlink-legacy
+        members:
+          description: List of struct members. Only scalars and strings members allowed.
+          type: array
+          items:
+            type: object
+            required: [ name, type ]
+            additionalProperties: False
+            properties:
+              name:
+                $ref: '#/$defs/name-cap'
+              type:
+                description: |
+                  The netlink attribute type. Members of type 'binary' or 'pad'
+                  must also have the 'len' property set.
+                enum: [ u8, u16, u32, u64, s8, s16, s32, s64, string, binary, pad ]
+              len:
+                $ref: '#/$defs/len-or-define'
+              byte-order:
+                enum: [ little-endian, big-endian ]
+              doc:
+                description: Documentation for the struct member attribute.
+                type: string
+              enum:
+                description: Name of the enum type used for the attribute.
+                type: string
+              enum-as-flags:
+                description: |
+                  Treat the enum as flags. In most cases enum is either used as flags or as values.
+                  Sometimes, however, both forms are necessary, in which case header contains the enum
+                  form while specific attributes may request to convert the values into a bitfield.
+                type: boolean
+              display-hint: &display-hint
+                description: |
+                  Optional format indicator that is intended only for choosing
+                  the right formatting mechanism when displaying values of this
+                  type.
+                enum: [ hex, mac, fddi, ipv4, ipv6, ipv4-or-v6, uuid ]
+              struct:
+                description: Name of the nested struct type.
+                type: string
+            if:
+              properties:
+                type:
+                  const: pad
+            then:
+              required: [ len ]
+            if:
+              properties:
+                type:
+                  const: binary
+            then:
+              oneOf:
+                - required: [ len ]
+                - required: [ struct ]
+        # End genetlink-legacy
+
+  attribute-sets:
+    description: Definition of attribute spaces for this family.
+    type: array
+    items:
+      description: Definition of a single attribute space.
+      type: object
+      required: [ name, attributes ]
+      additionalProperties: False
+      properties:
+        name:
+          description: |
+            Name used when referring to this space in other definitions, not used outside of the spec.
+          $ref: '#/$defs/name'
+        name-prefix:
+          description: |
+            Prefix for the C enum name of the attributes. Default family[name]-set[name]-a-
+          type: string
+        enum-name:
+          description: |
+            Name for the enum type of the attribute, if empty no name will be used.
+          type: [ string, "null" ]
+        doc:
+          description: Documentation of the space.
+          type: string
+        subset-of:
+          description: |
+            Name of another space which this is a logical part of. Sub-spaces can be used to define
+            a limited group of attributes which are used in a nest.
+          type: string
+        # Start genetlink-c
+        attr-cnt-name:
+          description: The explicit name for constant holding the count of attributes (last attr + 1).
+          type: string
+        attr-max-name:
+          description: The explicit name for last member of attribute enum.
+          type: string
+        header:
+          description: For C-compatible languages, header which already defines this attribute set.
+          type: string
+        # End genetlink-c
+        attributes:
+          description: List of attributes in the space.
+          type: array
+          items:
+            type: object
+            required: [ name ]
+            additionalProperties: False
+            properties:
+              name:
+                $ref: '#/$defs/name'
+              type: &attr-type
+                description: The netlink attribute type
+                enum: [ unused, pad, flag, binary, bitfield32,
+                        uint, sint, u8, u16, u32, u64, s8, s16, s32, s64,
+                        string, nest, indexed-array, nest-type-value,
+                        sub-message ]
+              doc:
+                description: Documentation of the attribute.
+                type: string
+              value:
+                description: Value for the enum item representing this attribute in the uAPI.
+                $ref: '#/$defs/uint'
+              type-value:
+                description: Name of the value extracted from the type of a nest-type-value attribute.
+                type: array
+                items:
+                  type: string
+              byte-order:
+                enum: [ little-endian, big-endian ]
+              multi-attr:
+                type: boolean
+              nested-attributes:
+                description: Name of the space (sub-space) used inside the attribute.
+                type: string
+              enum:
+                description: Name of the enum type used for the attribute.
+                type: string
+              enum-as-flags:
+                description: |
+                  Treat the enum as flags. In most cases enum is either used as flags or as values.
+                  Sometimes, however, both forms are necessary, in which case header contains the enum
+                  form while specific attributes may request to convert the values into a bitfield.
+                type: boolean
+              checks:
+                description: Kernel input validation.
+                type: object
+                additionalProperties: False
+                properties:
+                  flags-mask:
+                    description: Name of the flags constant on which to base mask (unsigned scalar types only).
+                    type: string
+                  min:
+                    description: Min value for an integer attribute.
+                    $ref: '#/$defs/len-or-limit'
+                  max:
+                    description: Max value for an integer attribute.
+                    $ref: '#/$defs/len-or-limit'
+                  min-len:
+                    description: Min length for a binary attribute.
+                    $ref: '#/$defs/len-or-define'
+                  max-len:
+                    description: Max length for a string or a binary attribute.
+                    $ref: '#/$defs/len-or-define'
+                  exact-len:
+                    description: Exact length for a string or a binary attribute.
+                    $ref: '#/$defs/len-or-define'
+                  unterminated-ok:
+                    description: |
+                      For string attributes, do not check whether attribute
+                      contains the terminating null character.
+                    type: boolean
+              sub-type: *attr-type
+              display-hint: *display-hint
+              # Start genetlink-c
+              name-prefix:
+                type: string
+              # End genetlink-c
+              # Start genetlink-legacy
+              struct:
+                description: Name of the struct type used for the attribute.
+                type: string
+              # End genetlink-legacy
+              # Start netlink-raw
+              sub-message:
+                description: |
+                  Name of the sub-message definition to use for the attribute.
+                type: string
+              selector:
+                description: |
+                  Name of the attribute to use for dynamic selection of sub-message
+                  format specifier.
+                type: string
+              # End netlink-raw
+
+      # Make sure name-prefix does not appear in subsets (subsets inherit naming)
+      dependencies:
+        name-prefix:
+          not:
+            required: [ subset-of ]
+        subset-of:
+          not:
+            required: [ name-prefix ]
+
+      # type property is only required if not in subset definition
+      if:
+        properties:
+          subset-of:
+            not:
+              type: string
+      then:
+        properties:
+          attributes:
+            items:
+              required: [ type ]
+
+  # Start netlink-raw
+  sub-messages:
+    description: Definition of sub message attributes
+    type: array
+    items:
+      type: object
+      additionalProperties: False
+      required: [ name, formats ]
+      properties:
+        name:
+          description: Name of the sub-message definition
+          type: string
+        formats:
+          description: Dynamically selected format specifiers
+          type: array
+          items:
+            type: object
+            additionalProperties: False
+            required: [ value ]
+            properties:
+              value:
+                description: |
+                  Value to match for dynamic selection of sub-message format
+                  specifier.
+                type: string
+              fixed-header:
+                description: |
+                  Name of the struct definition to use as the fixed header
+                  for the sub message.
+                type: string
+              attribute-set:
+                description: |
+                  Name of the attribute space from which to resolve attributes
+                  in the sub message.
+                type: string
+  # End netlink-raw
+
+  operations:
+    description: Operations supported by the protocol.
+    type: object
+    required: [ list ]
+    additionalProperties: False
+    properties:
+      enum-model:
+        description: |
+          The model of assigning values to the operations.
+          "unified" is the recommended model where all message types belong
+          to a single enum.
+          "directional" has the messages sent to the kernel and from the kernel
+          enumerated separately.
+        enum: [ unified, directional ] # Trim
+      name-prefix:
+        description: |
+          Prefix for the C enum name of the command. The name is formed by concatenating
+          the prefix with the upper case name of the command, with dashes replaced by underscores.
+        type: string
+      enum-name:
+        description: |
+          Name for the enum type with commands, if empty no name will be used.
+        type: [ string, "null" ]
+      async-prefix:
+        description: Same as name-prefix but used to render notifications and events to separate enum.
+        type: string
+      async-enum:
+        description: |
+          Name for the enum type with commands, if empty no name will be used.
+        type: [ string, "null" ]
+      # Start genetlink-legacy
+      fixed-header: &fixed-header
+        description: |
+          Name of the structure defining the optional fixed-length protocol
+          header. This header is placed in a message after the netlink and
+          genetlink headers and before any attributes.
+        type: string
+      # End genetlink-legacy
+      list:
+        description: List of commands
+        type: array
+        items:
+          type: object
+          additionalProperties: False
+          required: [ name, doc ]
+          properties:
+            name:
+              description: Name of the operation, also defining its C enum value in uAPI.
+              $ref: '#/$defs/name'
+            doc:
+              description: Documentation for the command.
+              type: string
+            value:
+              description: Value for the enum in the uAPI.
+              $ref: '#/$defs/uint'
+            attribute-set:
+              description: |
+                Attribute space from which attributes directly in the requests and replies
+                to this command are defined.
+              type: string
+            flags: &cmd_flags
+              description: Command flags.
+              type: array
+              items:
+                enum: [ admin-perm ]
+            dont-validate:
+              description: Kernel attribute validation flags.
+              type: array
+              items:
+                enum: [ strict, dump ]
+            # Start genetlink-legacy
+            fixed-header: *fixed-header
+            # End genetlink-legacy
+            do: &subop-type
+              description: Main command handler.
+              type: object
+              additionalProperties: False
+              properties:
+                request: &subop-attr-list
+                  description: Definition of the request message for a given command.
+                  type: object
+                  additionalProperties: False
+                  properties:
+                    attributes:
+                      description: |
+                        Names of attributes from the attribute-set (not full attribute
+                        definitions, just names).
+                      type: array
+                      items:
+                        type: string
+                    # Start genetlink-legacy
+                    value:
+                      description: |
+                        ID of this message if value for request and response differ,
+                        i.e. requests and responses have different message enums.
+                      $ref: '#/$defs/uint'
+                    # End genetlink-legacy
+                reply: *subop-attr-list
+                pre:
+                  description: Hook for a function to run before the main callback (pre_doit or start).
+                  type: string
+                post:
+                  description: Hook for a function to run after the main callback (post_doit or done).
+                  type: string
+            dump: *subop-type
+            notify:
+              description: Name of the command sharing the reply type with this notification.
+              type: string
+            event:
+              type: object
+              additionalProperties: False
+              properties:
+                attributes:
+                  description: Explicit list of the attributes for the notification.
+                  type: array
+                  items:
+                    type: string
+            mcgrp:
+              description: Name of the multicast group generating given notification.
+              type: string
+  mcast-groups:
+    description: List of multicast groups.
+    type: object
+    required: [ list ]
+    additionalProperties: False
+    properties:
+      list:
+        description: List of groups.
+        type: array
+        items:
+          type: object
+          required: [ name ]
+          additionalProperties: False
+          properties:
+            name:
+              description: |
+                The name for the group, used to form the define and the value of the define.
+              type: string
+            # Start genetlink-c
+            c-define-name:
+              description: Override for the name of the define in C uAPI.
+              type: string
+            # End genetlink-c
+            flags: *cmd_flags
+            # Start netlink-raw
+            value:
+              description: Value of the netlink multicast group in the uAPI.
+              type: integer
+            # End netlink-raw