Even though it is documented how to specifiy efi parameters, it is
possible to cause a kernel panic due to a dereference of a NULL pointer when
parsing such parameters if "efi" alone is given:

PANIC: early exception 0e rip 10:ffffffff812fb361 error 0 cr2 0
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.2.0-rc1+ #450
[ 0.000000]  ffffffff81fe20a9 ffffffff81e03d50 ffffffff8184bb0f 00000000000003f8
[ 0.000000]  0000000000000000 ffffffff81e03e08 ffffffff81f371a1 64656c62616e6520
[ 0.000000]  0000000000000069 000000000000005f 0000000000000000 0000000000000000
[ 0.000000] Call Trace:
[ 0.000000]  [<ffffffff8184bb0f>] dump_stack+0x45/0x57
[ 0.000000]  [<ffffffff81f371a1>] early_idt_handler_common+0x81/0xae
[ 0.000000]  [<ffffffff812fb361>] ? parse_option_str+0x11/0x90
[ 0.000000]  [<ffffffff81f4dd69>] arch_parse_efi_cmdline+0x15/0x42
[ 0.000000]  [<ffffffff81f376e1>] do_early_param+0x50/0x8a
[ 0.000000]  [<ffffffff8106b1b3>] parse_args+0x1e3/0x400
[ 0.000000]  [<ffffffff81f37a43>] parse_early_options+0x24/0x28
[ 0.000000]  [<ffffffff81f37691>] ? loglevel+0x31/0x31
[ 0.000000]  [<ffffffff81f37a78>] parse_early_param+0x31/0x3d
[ 0.000000]  [<ffffffff81f3ae98>] setup_arch+0x2de/0xc08
[ 0.000000]  [<ffffffff8109629a>] ? vprintk_default+0x1a/0x20
[ 0.000000]  [<ffffffff81f37b20>] start_kernel+0x90/0x423
[ 0.000000]  [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c
[ 0.000000]  [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef
[ 0.000000] RIP 0xffffffff81ba2efc

This panic is not reproducible with "efi=" as this will result in a non-NULL
zero-length string.

Thus, verify that the pointer to the parameter string is not NULL. This is
consistent with other parameter-parsing functions which check for NULL pointers.

Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

Pull an EFI fix from Matt Fleming:

 - Fix a bug in the Common Platform Error Record (CPER) driver that
   caused old UEFI spec (< 2.3) versions of the memory error record
   structure to be declared invalid. (Tony Luck)

Signed-off-by: Ingo Molnar <mingo@kernel.org>

The memory error record structure includes as its first field a
bitmask of which subsequent fields are valid. The allows new fields
to be added to the structure while keeping compatibility with older
software that parses these records. This mechanism was used between
versions 2.2 and 2.3 to add four new fields, growing the size of the
structure from 73 bytes to 80. But Linux just added all the new
fields so this test:
	if (gdata->error_data_length >= sizeof(*mem_err))
		cper_print_mem(newpfx, mem_err);
	else
		goto err_section_too_small;
now make Linux complain about old format records being too short.

Add a definition for the old format of the structure and use that
for the minimum size check. Pass the actual size to cper_print_mem()
so it can sanity check the validation_bits field to ensure that if
a BIOS using the old format sets bits as if it were new, we won't
access fields beyond the end of the structure.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

Pull user namespace updates from Eric Biederman:
 "Long ago and far away when user namespaces where young it was realized
  that allowing fresh mounts of proc and sysfs with only user namespace
  permissions could violate the basic rule that only root gets to decide
  if proc or sysfs should be mounted at all.

  Some hacks were put in place to reduce the worst of the damage could
  be done, and the common sense rule was adopted that fresh mounts of
  proc and sysfs should allow no more than bind mounts of proc and
  sysfs.  Unfortunately that rule has not been fully enforced.

  There are two kinds of gaps in that enforcement.  Only filesystems
  mounted on empty directories of proc and sysfs should be ignored but
  the test for empty directories was insufficient.  So in my tree
  directories on proc, sysctl and sysfs that will always be empty are
  created specially.  Every other technique is imperfect as an ordinary
  directory can have entries added even after a readdir returns and
  shows that the directory is empty.  Special creation of directories
  for mount points makes the code in the kernel a smidge clearer about
  it's purpose.  I asked container developers from the various container
  projects to help test this and no holes were found in the set of mount
  points on proc and sysfs that are created specially.

  This set of changes also starts enforcing the mount flags of fresh
  mounts of proc and sysfs are consistent with the existing mount of
  proc and sysfs.  I expected this to be the boring part of the work but
  unfortunately unprivileged userspace winds up mounting fresh copies of
  proc and sysfs with noexec and nosuid clear when root set those flags
  on the previous mount of proc and sysfs.  So for now only the atime,
  read-only and nodev attributes which userspace happens to keep
  consistent are enforced.  Dealing with the noexec and nosuid
  attributes remains for another time.

  This set of changes also addresses an issue with how open file
  descriptors from /proc/<pid>/ns/* are displayed.  Recently readlink of
  /proc/<pid>/fd has been triggering a WARN_ON that has not been
  meaningful since it was added (as all of the code in the kernel was
  converted) and is not now actively wrong.

  There is also a short list of issues that have not been fixed yet that
  I will mention briefly.

  It is possible to rename a directory from below to above a bind mount.
  At which point any directory pointers below the renamed directory can
  be walked up to the root directory of the filesystem.  With user
  namespaces enabled a bind mount of the bind mount can be created
  allowing the user to pick a directory whose children they can rename
  to outside of the bind mount.  This is challenging to fix and doubly
  so because all obvious solutions must touch code that is in the
  performance part of pathname resolution.

  As mentioned above there is also a question of how to ensure that
  developers by accident or with purpose do not introduce exectuable
  files on sysfs and proc and in doing so introduce security regressions
  in the current userspace that will not be immediately obvious and as
  such are likely to require breaking userspace in painful ways once
  they are recognized"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  vfs: Remove incorrect debugging WARN in prepend_path
  mnt: Update fs_fully_visible to test for permanently empty directories
  sysfs: Create mountpoints with sysfs_create_mount_point
  sysfs: Add support for permanently empty directories to serve as mount points.
  kernfs: Add support for always empty directories.
  proc: Allow creating permanently empty directories that serve as mount points
  sysctl: Allow creating permanently empty directories that serve as mountpoints.
  fs: Add helper functions for permanently empty directories.
  vfs: Ignore unlocked mounts in fs_fully_visible
  mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
  mnt: Refactor the logic for mounting sysfs and proc in a user namespace

Pull devicetree updates from Grant Likely:
 "A whole lot of bug fixes.

  Nothing stands out here except the ability to enable CONFIG_OF on
  every architecture, and an import of a newer version of dtc"

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (22 commits)
  of/irq: Rename "intc_desc" to "of_intc_desc" to fix OF on sh
  of/irq: Fix pSeries boot failure
  Documentation: DT: Fix a typo in the filename "lantiq,<chip>-pinumx.txt"
  of: define of_find_node_by_phandle for !CONFIG_OF
  of/address: use atomic allocation in pci_register_io_range()
  of: Add vendor prefix for Zodiac Inflight Innovations
  dt/fdt: add empty versions of early_init_dt_*_memory_arch
  of: clean-up unnecessary libfdt include paths
  of: make unittest select OF_EARLY_FLATTREE instead of depend on it
  of: make CONFIG_OF user selectable
  MIPS: prepare for user enabling of CONFIG_OF
  of/fdt: fix argument name and add comments of unflatten_dt_node()
  of: return NUMA_NO_NODE from fallback of_node_to_nid()
  tps6507x.txt: Remove executable permission
  of/overlay: Grammar s/an negative/a negative/
  of/fdt: Make fdt blob input parameters of unflatten functions const
  of: add helper function to retrive match data
  of: Grammar s/property exist/property exists/
  of: Move OF flags to be visible even when !CONFIG_OF
  scripts/dtc: Update to upstream version 9d3649bd3be245c9
  ...

This allows for better documentation in the code and
it allows for a simpler and fully correct version of
fs_fully_visible to be written.

The mount points converted and their filesystems are:
/sys/hypervisor/s390/       s390_hypfs
/sys/kernel/config/         configfs
/sys/kernel/debug/          debugfs
/sys/firmware/efi/efivars/  efivarfs
/sys/fs/fuse/connections/   fusectl
/sys/fs/pstore/             pstore
/sys/kernel/tracing/        tracefs
/sys/fs/cgroup/             cgroup
/sys/kernel/security/       securityfs
/sys/fs/selinux/            selinuxfs
/sys/fs/smackfs/            smackfs

Cc: stable@vger.kernel.org
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Pull EFI build fix from Matt Fleming:

  - Fix ESRT build breakage on ia64 reported by Guenter Roeck. (Peter Jones)

Signed-off-by: Ingo Molnar <mingo@kernel.org>

So, I'm told this problem exists in the world:

 > Subject: Build error in -next due to 'efi: Add esrt support'
 >
 > Building ia64:defconfig ... failed
 > --------------
 > Error log:
 >
 > drivers/firmware/efi/esrt.c:28:31: fatal error: asm/early_ioremap.h: No such file or directory
 >

I'm not really sure how it's okay that we have things in asm-generic on
some platforms but not others - is having it the same everywhere not the
whole point of asm-generic?

That said, ia64 doesn't have early_ioremap.h .  So instead, since it's
difficult to imagine new IA64 machines with UEFI 2.5, just don't build
this code there.

To me this looks like a workaround - doing something like:

generic-y += early_ioremap.h

in arch/ia64/include/asm/Kbuild would appear to be more correct, but
ia64 has its own early_memremap() decl in arch/ia64/include/asm/io.h ,
and it's a macro.  So adding the above /and/ requiring that asm/io.h be
included /after/ asm/early_ioremap.h in all cases would fix it, but
that's pretty ugly as well.  Since I'm not going to spend the rest of my
life rectifying ia64 headers vs "generic" headers that aren't generic,
it's much simpler to just not build there.

Note that I've only actually tried to build this patch on x86_64, but
esrt.o still gets built there, and that would seem to demonstrate that
the conditional building is working correctly at all the places the code
built before.  I no longer have any ia64 machines handy to test that the
exclusion actually works there.

Signed-off-by: Peter Jones <pjones@redhat.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
(Compile-)Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

With the libfdt include fixups to use "" instead of <> in the
latest dtc import in commit 4760597 (scripts/dtc: Update to upstream
version 9d3649bd3be245c9), it is no longer necessary to add explicit
include paths to use libfdt. Remove these across the kernel.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: linux-mips@linux-mips.org
Cc: linuxppc-dev@lists.ozlabs.org