Merge tag 'docs-for-linus' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "Some big changes this month, headlined by the addition of a new
  formatted documentation mechanism based on the Sphinx system.

  The objectives here are to make it easier to create better-integrated
  (and more attractive) documents while (eventually) dumping our
  one-of-a-kind, cobbled-together system for something that is widely
  used and maintained by others.  There's a fair amount of information
  what's being done, why, and how to use it in:

    https://lwn.net/Articles/692704/
    https://lwn.net/Articles/692705/

  Closer to home, Documentation/kernel-documentation.rst describes how
  it works.

  For now, the new system exists alongside the old one; you should soon
  see the GPU documentation converted over in the DRM pull and some
  significant media conversion work as well.  Once all the docs have
  been moved over and we're convinced that the rough edges (of which are
  are a few) have been smoothed over, the DocBook-based stuff should go
  away.

  Primary credit is to Jani Nikula for doing the heavy lifting to make
  this stuff actually work; there has also been notable effort from
  Markus Heiser, Daniel Vetter, and Mauro Carvalho Chehab.

  Expect a couple of conflicts on the new index.rst file over the course
  of the merge window; they are trivially resolvable.  That file may be
  a bit of a conflict magnet in the short term, but I don't expect that
  situation to last for any real length of time.

  Beyond that, of course, we have the usual collection of tweaks,
  updates, and typo fixes"

* tag 'docs-for-linus' of git://git.lwn.net/linux: (77 commits)
  doc-rst: kernel-doc: fix handling of address_space tags
  Revert "doc/sphinx: Enable keep_warnings"
  doc-rst: kernel-doc directive, fix state machine reporter
  docs: deprecate kernel-doc-nano-HOWTO.txt
  doc/sphinx: Enable keep_warnings
  Documentation: add watermark_scale_factor to the list of vm systcl file
  kernel-doc: Fix up warning output
  docs: Get rid of some kernel-documentation warnings
  doc-rst: add an option to ignore DocBooks when generating docs
  workqueue: Fix a typo in workqueue.txt
  Doc: ocfs: Fix typo in filesystems/ocfs2-online-filecheck.txt
  Documentation/sphinx: skip build if user requested specific DOCBOOKS
  Documentation: add cleanmediadocs to the documentation targets
  Add .pyc files to .gitignore
  Doc: PM: Fix a typo in intel_powerclamp.txt
  doc-rst: flat-table directive - initial implementation
  Documentation: add meta-documentation for Sphinx and kernel-doc
  Documentation: tiny typo fix in usb/gadget_multi.txt
  Documentation: fix wrong value in md.txt
  bcache: documentation formatting, edited for clarity, stripe alignment notes
  ...

1 files changed, 18 insertions, 10 deletions

diff --git a/Documentation/security/self-protection.txt b/Documentation/security/self-protection.txt
index babd6378ec05..3010576c9fca 100644
--- a/Documentation/security/self-protection.txt
+++ b/Documentation/security/self-protection.txt
@@ -183,8 +183,9 @@ provide meaningful defenses.
 ### Canaries, blinding, and other secrets
 
 It should be noted that things like the stack canary discussed earlier
-are technically statistical defenses, since they rely on a (leakable)
-secret value.
+are technically statistical defenses, since they rely on a secret value,
+and such values may become discoverable through an information exposure
+flaw.
 
 Blinding literal values for things like JITs, where the executable
 contents may be partially under the control of userspace, need a similar
@@ -199,8 +200,8 @@ working?) in order to maximize their success.
 Since the location of kernel memory is almost always instrumental in
 mounting a successful attack, making the location non-deterministic
 raises the difficulty of an exploit. (Note that this in turn makes
-the value of leaks higher, since they may be used to discover desired
-memory locations.)
+the value of information exposures higher, since they may be used to
+discover desired memory locations.)
 
 #### Text and module base
 
@@ -222,14 +223,21 @@ become more difficult to locate.
 Much of the kernel's dynamic memory (e.g. kmalloc, vmalloc, etc) ends up
 being relatively deterministic in layout due to the order of early-boot
 initializations. If the base address of these areas is not the same
-between boots, targeting them is frustrated, requiring a leak specific
-to the region.
+between boots, targeting them is frustrated, requiring an information
+exposure specific to the region.
+
+#### Structure layout
+
+By performing a per-build randomization of the layout of sensitive
+structures, attacks must either be tuned to known kernel builds or expose
+enough kernel memory to determine structure layouts before manipulating
+them.
 
 
-## Preventing Leaks
+## Preventing Information Exposures
 
 Since the locations of sensitive structures are the primary target for
-attacks, it is important to defend against leaks of both kernel memory
+attacks, it is important to defend against exposure of both kernel memory
 addresses and kernel memory contents (since they may contain kernel
 addresses or other sensitive things like canary values).
 
@@ -250,8 +258,8 @@ sure structure holes are cleared.
 When releasing memory, it is best to poison the contents (clear stack on
 syscall return, wipe heap memory on a free), to avoid reuse attacks that
 rely on the old contents of memory. This frustrates many uninitialized
-variable attacks, stack info leaks, heap info leaks, and use-after-free
-attacks.
+variable attacks, stack content exposures, heap content exposures, and
+use-after-free attacks.
 
 ### Destination tracking