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, 207 insertions, 0 deletions

diff --git a/drivers/net/ppp/Kconfig b/drivers/net/ppp/Kconfig
new file mode 100644
index 000000000..4047f13b8
--- /dev/null
+++ b/drivers/net/ppp/Kconfig
@@ -0,0 +1,207 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# PPP network device configuration
+#
+
+config PPP
+	tristate "PPP (point-to-point protocol) support"
+	select SLHC
+	help
+	  PPP (Point to Point Protocol) is a newer and better SLIP.  It serves
+	  the same purpose: sending Internet traffic over telephone (and other
+	  serial) lines.  Ask your access provider if they support it, because
+	  otherwise you can't use it; most Internet access providers these
+	  days support PPP rather than SLIP.
+
+	  To use PPP, you need an additional program called pppd, available at
+	  <https://ppp.samba.org>.  Make sure that you have the version of pppd
+	  recommended in <file:Documentation/Changes>.
+	  The PPP option enlarges your kernel by about 16 KB.
+
+	  There are actually two versions of PPP: the traditional PPP for
+	  asynchronous lines, such as regular analog phone lines, and
+	  synchronous PPP which can be used over digital ISDN lines for
+	  example.  If you want to use PPP over phone lines or other
+	  asynchronous serial lines, you need to say Y (or M) here and also to
+	  the next option, "PPP support for async serial ports".  For PPP over
+	  synchronous lines, you should say Y (or M) here and to "Support
+	  synchronous PPP", below.
+
+	  If you said Y to "Version information on all symbols" above, then
+	  you cannot compile the PPP driver into the kernel; you can then only
+	  compile it as a module. To compile this driver as a module, choose M
+	  here. The module will be called ppp_generic.
+
+if PPP
+
+config PPP_BSDCOMP
+	tristate "PPP BSD-Compress compression"
+	help
+	  Support for the BSD-Compress compression method for PPP, which uses
+	  the LZW compression method to compress each PPP packet before it is
+	  sent over the wire. The machine at the other end of the PPP link
+	  (usually your ISP) has to support the BSD-Compress compression
+	  method as well for this to be useful. Even if they don't support it,
+	  it is safe to say Y here.
+
+	  The PPP Deflate compression method ("PPP Deflate compression",
+	  above) is preferable to BSD-Compress, because it compresses better
+	  and is patent-free.
+
+	  Note that the BSD compression code will always be compiled as a
+	  module; it is called bsd_comp and will show up in the directory
+	  modules once you have said "make modules". If unsure, say N.
+
+config PPP_DEFLATE
+	tristate "PPP Deflate compression"
+	select ZLIB_INFLATE
+	select ZLIB_DEFLATE
+	help
+	  Support for the Deflate compression method for PPP, which uses the
+	  Deflate algorithm (the same algorithm that gzip uses) to compress
+	  each PPP packet before it is sent over the wire.  The machine at the
+	  other end of the PPP link (usually your ISP) has to support the
+	  Deflate compression method as well for this to be useful.  Even if
+	  they don't support it, it is safe to say Y here.
+
+	  To compile this driver as a module, choose M here.
+
+config PPP_FILTER
+	bool "PPP filtering"
+	help
+	  Say Y here if you want to be able to filter the packets passing over
+	  PPP interfaces.  This allows you to control which packets count as
+	  activity (i.e. which packets will reset the idle timer or bring up
+	  a demand-dialed link) and which packets are to be dropped entirely.
+	  You need to say Y here if you wish to use the pass-filter and
+	  active-filter options to pppd.
+
+	  If unsure, say N.
+
+config PPP_MPPE
+	tristate "PPP MPPE compression (encryption)"
+	select CRYPTO_LIB_ARC4
+	select CRYPTO_LIB_SHA1
+	help
+	  Support for the MPPE Encryption protocol, as employed by the
+	  Microsoft Point-to-Point Tunneling Protocol.
+
+	  See http://pptpclient.sourceforge.net/ for information on
+	  configuring PPTP clients and servers to utilize this method.
+
+config PPP_MULTILINK
+	bool "PPP multilink support"
+	help
+	  PPP multilink is a protocol (defined in RFC 1990) which allows you
+	  to combine several (logical or physical) lines into one logical PPP
+	  connection, so that you can utilize your full bandwidth.
+
+	  This has to be supported at the other end as well and you need a
+	  version of the pppd daemon which understands the multilink protocol.
+
+	  If unsure, say N.
+
+config PPPOATM
+	tristate "PPP over ATM"
+	depends on ATM
+	help
+	  Support PPP (Point to Point Protocol) encapsulated in ATM frames.
+	  This implementation does not yet comply with section 8 of RFC2364,
+	  which can lead to bad results if the ATM peer loses state and
+	  changes its encapsulation unilaterally.
+
+config PPPOX
+	tristate
+
+config PPPOE
+	tristate "PPP over Ethernet"
+	select PPPOX
+	help
+	  Support for PPP over Ethernet.
+
+	  To work in client mode, pppd version 2.4.2 or later is required.
+	  To work in server mode, the pppoe-server command from the RP-PPPoE
+	  package is also required, available at
+	  <https://dianne.skoll.ca/projects/rp-pppoe/>.
+
+choice
+	prompt "Number of PPPoE hash bits"
+	default PPPOE_HASH_BITS_4
+	depends on PPPOE
+	help
+		Select the number of bits used for hashing PPPoE interfaces.
+
+		Larger sizes reduces the risk of hash collisions at the cost
+		of slightly increased memory usage.
+
+		This hash table is on a per outer ethernet interface.
+
+config PPPOE_HASH_BITS_1
+	bool "1 bit (2 buckets)"
+
+config PPPOE_HASH_BITS_2
+	bool "2 bits (4 buckets)"
+
+config PPPOE_HASH_BITS_4
+	bool "4 bits (16 buckets)"
+
+config PPPOE_HASH_BITS_8
+	bool "8 bits (256 buckets)"
+
+endchoice
+
+config PPPOE_HASH_BITS
+	int
+	default 1 if PPPOE_HASH_BITS_1
+	default 2 if PPPOE_HASH_BITS_2
+	default 4 if PPPOE_HASH_BITS_4
+	default 8 if PPPOE_HASH_BITS_8
+	default 4
+
+config PPTP
+	tristate "PPP over IPv4 (PPTP)"
+	depends on NET_IPGRE_DEMUX
+	select PPPOX
+	help
+	  Support for PPP over IPv4.(Point-to-Point Tunneling Protocol)
+
+	  This driver requires pppd plugin to work in client mode or
+	  modified pptpd (poptop) to work in server mode.
+	  See http://accel-pptp.sourceforge.net/ for information how to
+	  utilize this module.
+
+config PPPOL2TP
+	tristate "PPP over L2TP"
+	depends on L2TP
+	select PPPOX
+	help
+	  Support for PPP-over-L2TP socket family. L2TP is a protocol
+	  used by ISPs and enterprises to tunnel PPP traffic over UDP
+	  tunnels. L2TP is replacing PPTP for VPN uses.
+if TTY
+
+config PPP_ASYNC
+	tristate "PPP support for async serial ports"
+	select CRC_CCITT
+	help
+	  Say Y (or M) here if you want to be able to use PPP over standard
+	  asynchronous serial ports, such as COM1 or COM2 on a PC.  If you use
+	  a modem (not a synchronous or ISDN modem) to contact your ISP, you
+	  need this option.
+
+	  To compile this driver as a module, choose M here.
+
+	  If unsure, say Y.
+
+config PPP_SYNC_TTY
+	tristate "PPP support for sync tty ports"
+	help
+	  Say Y (or M) here if you want to be able to use PPP over synchronous
+	  (HDLC) tty devices. These devices are often used for high-speed leased
+	  lines like T1/E1.
+
+	  To compile this driver as a module, choose M here.
+
+endif # TTY
+
+endif # PPP