From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sat, 9 Mar 2019 17:06:15 +0000 (-0800)
Subject: Merge tag 'gcc-plugins-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git... 
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=2bb995405fe52dd893db57456556e8dc4fce35a7;p=openwrt%2Fstaging%2Fblogic.git

Merge tag 'gcc-plugins-v5.1-rc1' of git://git./linux/kernel/git/kees/linux

Pull gcc-plugins updates from Kees Cook:
 "This adds additional type coverage to the existing structleak plugin
  and adds a large set of selftests to help evaluate stack variable
  zero-initialization coverage.

  That can be used to test whatever instrumentation might be performing
  zero-initialization: either with the structleak plugin or with Clang's
  coming "-ftrivial-auto-var-init=zero" option.

  Summary:

   - Add scalar and array initialization coverage

   - Refactor Kconfig to make options more clear

   - Add self-test module for testing automatic initialization"

* tag 'gcc-plugins-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  lib: Introduce test_stackinit module
  gcc-plugins: structleak: Generalize to all variable types
---

2bb995405fe52dd893db57456556e8dc4fce35a7
diff --cc lib/Kconfig.debug
index d765d36f8737,6f543a4bc704..e718487c97c3
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@@ -2015,7 -1999,18 +2015,17 @@@ config TEST_OBJAG
  	  Enable this option to test object aggregation manager on boot
  	  (or module load).
  
 -	  If unsure, say N.
  
+ config TEST_STACKINIT
+ 	tristate "Test level of stack variable initialization"
+ 	help
+ 	  Test if the kernel is zero-initializing stack variables and
+ 	  padding. Coverage is controlled by compiler flags,
+ 	  CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF,
+ 	  or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL.
+ 
+ 	  If unsure, say N.
+ 
  endif # RUNTIME_TESTING_MENU
  
  config MEMTEST
diff --cc lib/Makefile
index c7ae0b3e4535,c81a66d4d00d..647517940b29
--- a/lib/Makefile
+++ b/lib/Makefile
@@@ -77,9 -76,8 +77,10 @@@ obj-$(CONFIG_TEST_KMOD) += test_kmod.
  obj-$(CONFIG_TEST_DEBUG_VIRTUAL) += test_debug_virtual.o
  obj-$(CONFIG_TEST_MEMCAT_P) += test_memcat_p.o
  obj-$(CONFIG_TEST_OBJAGG) += test_objagg.o
+ obj-$(CONFIG_TEST_STACKINIT) += test_stackinit.o
  
 +obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/
 +
  ifeq ($(CONFIG_DEBUG_KOBJECT),y)
  CFLAGS_kobject.o += -DDEBUG
  CFLAGS_kobject_uevent.o += -DDEBUG
diff --cc scripts/gcc-plugins/Kconfig
index d9fd9988ef27,d0cc92e48f6f..74271dba4f94
--- a/scripts/gcc-plugins/Kconfig
+++ b/scripts/gcc-plugins/Kconfig
@@@ -67,13 -67,22 +67,18 @@@ config GCC_PLUGIN_LATENT_ENTROP
  	   * https://pax.grsecurity.net/
  
  config GCC_PLUGIN_STRUCTLEAK
- 	bool "Force initialization of variables containing userspace addresses"
+ 	bool "Zero initialize stack variables"
 -	# Currently STRUCTLEAK inserts initialization out of live scope of
 -	# variables from KASAN point of view. This leads to KASAN false
 -	# positive reports. Prohibit this combination for now.
 -	depends on !KASAN_EXTRA
  	help
- 	  This plugin zero-initializes any structures containing a
- 	  __user attribute. This can prevent some classes of information
- 	  exposures.
- 
- 	  This plugin was ported from grsecurity/PaX. More information at:
+ 	  While the kernel is built with warnings enabled for any missed
+ 	  stack variable initializations, this warning is silenced for
+ 	  anything passed by reference to another function, under the
+ 	  occasionally misguided assumption that the function will do
+ 	  the initialization. As this regularly leads to exploitable
+ 	  flaws, this plugin is available to identify and zero-initialize
+ 	  such variables, depending on the chosen level of coverage.
+ 
+ 	  This plugin was originally ported from grsecurity/PaX. More
+ 	  information at:
  	   * https://grsecurity.net/
  	   * https://pax.grsecurity.net/