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, 197 insertions, 0 deletions

diff --git a/fs/nfsd/Kconfig b/fs/nfsd/Kconfig
new file mode 100644
index 000000000..ffb76761d
--- /dev/null
+++ b/fs/nfsd/Kconfig
@@ -0,0 +1,197 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config NFSD
+	tristate "NFS server support"
+	depends on INET
+	depends on FILE_LOCKING
+	depends on FSNOTIFY
+	select CRC32
+	select CRYPTO_LIB_MD5 if NFSD_LEGACY_CLIENT_TRACKING
+	select CRYPTO_LIB_SHA256 if NFSD_V4
+	select CRYPTO # required by RPCSEC_GSS_KRB5 and signed filehandles
+	select LOCKD
+	select SUNRPC
+	select EXPORTFS
+	select NFS_COMMON
+	select NFS_ACL_SUPPORT if NFSD_V2_ACL
+	select NFS_ACL_SUPPORT if NFSD_V3_ACL
+	depends on MULTIUSER
+	help
+	  Choose Y here if you want to allow other computers to access
+	  files residing on this system using Sun's Network File System
+	  protocol.  To compile the NFS server support as a module,
+	  choose M here: the module will be called nfsd.
+
+	  You may choose to use a user-space NFS server instead, in which
+	  case you can choose N here.
+
+	  To export local file systems using NFS, you also need to install
+	  user space programs which can be found in the Linux nfs-utils
+	  package, available from http://linux-nfs.org/.  More detail about
+	  the Linux NFS server implementation is available via the
+	  exports(5) man page.
+
+	  Below you can choose which versions of the NFS protocol are
+	  available to clients mounting the NFS server on this system.
+	  Support for NFS version 3 (RFC 1813) is always available when
+	  CONFIG_NFSD is selected.
+
+	  If unsure, say N.
+
+config NFSD_V2
+	bool "NFS server support for NFS version 2 (DEPRECATED)"
+	depends on NFSD
+	default n
+	help
+	  NFSv2 (RFC 1094) was the first publicly-released version of NFS.
+	  Unless you are hosting ancient (1990's era) NFS clients, you don't
+	  need this.
+
+	  If unsure, say N.
+
+config NFSD_V2_ACL
+	bool "NFS server support for the NFSv2 ACL protocol extension"
+	depends on NFSD_V2
+
+config NFSD_V3_ACL
+	bool "NFS server support for the NFSv3 ACL protocol extension"
+	depends on NFSD
+	help
+	  Solaris NFS servers support an auxiliary NFSv3 ACL protocol that
+	  never became an official part of the NFS version 3 protocol.
+	  This protocol extension allows applications on NFS clients to
+	  manipulate POSIX Access Control Lists on files residing on NFS
+	  servers.  NFS servers enforce POSIX ACLs on local files whether
+	  this protocol is available or not.
+
+	  This option enables support in your system's NFS server for the
+	  NFSv3 ACL protocol extension allowing NFS clients to manipulate
+	  POSIX ACLs on files exported by your system's NFS server.  NFS
+	  clients which support the Solaris NFSv3 ACL protocol can then
+	  access and modify ACLs on your NFS server.
+
+	  To store ACLs on your NFS server, you also need to enable ACL-
+	  related CONFIG options for your local file systems of choice.
+
+	  If unsure, say N.
+
+config NFSD_V4
+	bool "NFS server support for NFS version 4"
+	depends on NFSD && PROC_FS
+	select FS_POSIX_ACL
+	select RPCSEC_GSS_KRB5
+	select GRACE_PERIOD
+	select NFS_V4_2_SSC_HELPER if NFS_V4_2
+	help
+	  This option enables support in your system's NFS server for
+	  version 4 of the NFS protocol (RFC 3530).
+
+	  To export files using NFSv4, you need to install additional user
+	  space programs which can be found in the Linux nfs-utils package,
+	  available from http://linux-nfs.org/.
+
+	  If unsure, say N.
+
+config NFSD_PNFS
+	bool
+
+config NFSD_BLOCKLAYOUT
+	bool "NFSv4.1 server support for pNFS block layouts"
+	depends on NFSD_V4 && BLOCK
+	select NFSD_PNFS
+	select EXPORTFS_BLOCK_OPS
+	help
+	  This option enables support for the exporting pNFS block layouts
+	  in the kernel's NFS server. The pNFS block layout enables NFS
+	  clients to directly perform I/O to block devices accessible to both
+	  the server and the clients.  See RFC 5663 for more details.
+
+	  If unsure, say N.
+
+config NFSD_SCSILAYOUT
+	bool "NFSv4.1 server support for pNFS SCSI layouts"
+	depends on NFSD_V4 && BLOCK
+	select NFSD_PNFS
+	select EXPORTFS_BLOCK_OPS
+	help
+	  This option enables support for the exporting pNFS SCSI layouts
+	  in the kernel's NFS server. The pNFS SCSI layout enables NFS
+	  clients to directly perform I/O to SCSI devices accessible to both
+	  the server and the clients.  See draft-ietf-nfsv4-scsi-layout for
+	  more details.
+
+	  If unsure, say N.
+
+config NFSD_FLEXFILELAYOUT
+	bool "NFSv4.1 server support for pNFS Flex File layouts"
+	depends on NFSD_V4
+	select NFSD_PNFS
+	help
+	  This option enables support for the exporting pNFS Flex File
+	  layouts in the kernel's NFS server. The pNFS Flex File  layout
+	  enables NFS clients to directly perform I/O to NFSv3 devices
+	  accessible to both the server and the clients.  See
+	  draft-ietf-nfsv4-flex-files for more details.
+
+	  Warning, this server implements the bare minimum functionality
+	  to be a flex file server - it is for testing the client,
+	  not for use in production.
+
+	  If unsure, say N.
+
+config NFSD_V4_2_INTER_SSC
+	bool "NFSv4.2 inter server to server COPY"
+	depends on NFSD_V4 && NFS_V4_2
+	help
+	  This option enables support for NFSv4.2 inter server to
+	  server copy where the destination server calls the NFSv4.2
+	  client to read the data to copy from the source server.
+
+	  If unsure, say N.
+
+config NFSD_V4_SECURITY_LABEL
+	bool "Provide Security Label support for NFSv4 server"
+	depends on NFSD_V4 && SECURITY
+	help
+
+	Say Y here if you want enable fine-grained security label attribute
+	support for NFS version 4.  Security labels allow security modules like
+	SELinux and Smack to label files to facilitate enforcement of their policies.
+	Without this an NFSv4 mount will have the same label on each file.
+
+	If you do not wish to enable fine-grained security labels SELinux or
+	Smack policies on NFSv4 files, say N.
+
+config NFSD_LEGACY_CLIENT_TRACKING
+	bool "Support legacy NFSv4 client tracking methods (DEPRECATED)"
+	depends on NFSD_V4
+	default n
+	help
+	  The NFSv4 server needs to store a small amount of information on
+	  stable storage in order to handle state recovery after reboot. Most
+	  modern deployments upcall to a userland daemon for this (nfsdcld),
+	  but older NFS servers may store information directly in a
+	  recoverydir, or spawn a process directly using a usermodehelper
+	  upcall.
+
+	  These legacy client tracking methods have proven to be problematic
+	  and will be removed in the future. Say Y here if you need support
+	  for them in the interim.
+
+config NFSD_V4_POSIX_ACLS
+	bool "Support NFSv4 POSIX draft ACLs"
+	depends on NFSD_V4
+	default n
+	help
+	  Include experimental support for POSIX Access Control Lists
+	  (ACLs) in NFSv4 as specified in the IETF draft
+	  draft-ietf-nfsv4-posix-acls. This protocol extension enables
+	  NFSv4 clients to retrieve and modify POSIX ACLs on exported
+	  filesystems that support them.
+
+	  This feature is based on an unratified IETF draft
+	  specification that may change in ways that impact
+	  interoperability with existing clients. Enable only for
+	  testing environments or when interoperability with specific
+	  clients that implement this draft is required.
+
+	  If unsure, say N.