linux.git/lib, branch v5.2-rc1

slab: remove /proc/slab_allocators

2019-05-16T22:51:55+00:00

It turned out that DEBUG_SLAB_LEAK is still broken even after recent
recue efforts that when there is a large number of objects like
kmemleak_object which is normal on a debug kernel,

  # grep kmemleak /proc/slabinfo
  kmemleak_object   2243606 3436210 ...

reading /proc/slab_allocators could easily loop forever while processing
the kmemleak_object cache and any additional freeing or allocating
objects will trigger a reprocessing. To make a situation worse,
soft-lockups could easily happen in this sitatuion which will call
printk() to allocate more kmemleak objects to guarantee an infinite
loop.

Also, since it seems no one had noticed when it was totally broken
more than 2-year ago - see the commit fcf88917dd43 ("slab: fix a crash
by reading /proc/slab_allocators"), probably nobody cares about it
anymore due to the decline of the SLAB. Just remove it entirely.

Suggested-by: Vlastimil Babka 
Suggested-by: Linus Torvalds 
Signed-off-by: Qian Cai 
Signed-off-by: Linus Torvalds

Merge tag 'asm-generic-nommu' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

2019-05-16T18:26:37+00:00

Pull nommu generic uaccess updates from Arnd Bergmann:
 "asm-generic: kill  and improve nommu generic uaccess helpers

  Christoph Hellwig writes:

     This is a series doing two somewhat interwinded things. It improves
     the asm-generic nommu uaccess helper to optionally be entirely
     generic and not require any arch helpers for the actual uaccess.
     For the generic uaccess.h to actually be generically useful I also
     had to kill off the mess we made of , which really
     shouldn't exist on most architectures"

* tag 'asm-generic-nommu' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: optimize generic uaccess for 8-byte loads and stores
  asm-generic: provide entirely generic nommu uaccess
  arch: mostly remove 
  asm-generic: don't include  from

Merge branch 'linus' into x86/urgent, to pick up dependent changes

2019-05-16T07:04:48+00:00

Signed-off-by: Ingo Molnar

tools/testing/selftests/sysctl/sysctl.sh: add proc_do_large_bitmap() test case

2019-05-15T02:52:51+00:00

The kernel has only two users of proc_do_large_bitmap(), the kernel CPU
watchdog, and the ip_local_reserved_ports.  Refer to watchdog_cpumask
and ip_local_reserved_ports in Documentation for further details on
these.  When you input a large buffer into these, when it is larger than
PAGE_SIZE- 1, the input data gets misparsed, and the user get
incorrectly informed that the desired input value was set.  This commit
implements a test which mimics and exploits that use case, it uses a
bitmap size, as in the watchdog case.  The bitmap is used to test the
bitmap proc handler, proc_do_large_bitmap().

The next commit fixes this issue.

[akpm@linux-foundation.org: move proc_do_large_bitmap() export to EOF]
[mcgrof@kernel.org: use new target description for backward compatibility]
[mcgrof@kernel.org: augment test number to 50, ran into issues with bash string comparisons when testing up to 50 cases.]
[mcgrof@kernel.org: introduce and use verify_diff_proc_file() to use diff]
[mcgrof@kernel.org: use mktemp for tmp file]
[mcgrof@kernel.org: merge shell test and C code]
[mcgrof@kernel.org: commit log love]
[mcgrof@kernel.org: export proc_do_large_bitmap() to allow for the test
[mcgrof@kernel.org: check for the return value when writing to the proc file]
Link: http://lkml.kernel.org/r/20190320222831.8243-6-mcgrof@kernel.org
Signed-off-by: Eric Sandeen 
Signed-off-by: Luis Chamberlain 
Acked-by: Kees Cook 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

init: introduce DEBUG_MISC option

2019-05-15T02:52:50+00:00

Patch series "init: Do not select DEBUG_KERNEL by default", v5.

CONFIG_DEBUG_KERNEL has been designed to just enable Kconfig options.
Kernel code generatoin should not depend on CONFIG_DEBUG_KERNEL.

Proposed alternative plan: let's add a new symbol, something like
DEBUG_MISC ("Miscellaneous debug code that should be under a more
specific debug option but isn't"), make it depend on DEBUG_KERNEL and be
"default DEBUG_KERNEL" but allow itself to be turned off, and then
mechanically change the small handful of "#ifdef CONFIG_DEBUG_KERNEL" to
"#ifdef CONFIG_DEBUG_MISC".

This patch (of 5):

Introduce DEBUG_MISC ("Miscellaneous debug code that should be under a
more specific debug option but isn't"), make it depend on DEBUG_KERNEL
and be "default DEBUG_KERNEL" but allow itself to be turned off, and
then mechanically change the small handful of "#ifdef
CONFIG_DEBUG_KERNEL" to "#ifdef CONFIG_DEBUG_MISC".

Link: http://lkml.kernel.org/r/20190413224438.10802-2-okaya@kernel.org
Signed-off-by: Sinan Kaya 
Reviewed-by: Josh Triplett 
Reviewed-by: Kees Cook 
Cc: Anders Roxell 
Cc: Benjamin Herrenschmidt 
Cc: Christophe Leroy 
Cc:  Chris Zankel 
Cc: "David S. Miller" 
Cc: Florian Westphal 
Cc: Greg Kroah-Hartman 
Cc: James Hogan 
Cc: Jozsef Kadlecsik 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Pablo Neira Ayuso 
Cc: Paul Burton 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Cc: Thomas Bogendoerfer 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/test_vmalloc.c:test_func(): eliminate local `ret'

2019-05-15T02:52:49+00:00

Local 'ret' is unneeded and was poorly named: the variable `ret'
generally means the "the value which this function will return".

Cc: Roman Gushchin 
Cc: Uladzislau Rezki 
Cc: Michal Hocko 
Cc: Matthew Wilcox 
Cc: Thomas Garnier 
Cc: Oleksiy Avramchenko 
Cc: Steven Rostedt 
Cc: Joel Fernandes 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/test_bitmap: add tests for bitmap_parselist_user()

2019-05-15T02:52:49+00:00

Propagate existing bitmap_parselist() tests to bitmap_parselist_user().

Link: http://lkml.kernel.org/r/20190405173211.11373-6-ynorov@marvell.com
Signed-off-by: Yury Norov 
Reviewed-by: Andy Shevchenko 
Cc: Arnd Bergmann 
Cc: Kees Cook 
Cc: Matthew Wilcox 
Cc: Mike Travis 
Cc: Rasmus Villemoes 
Cc: Tetsuo Handa 
Cc: Guenter Roeck 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/test_bitmap: add testcases for bitmap_parselist()

2019-05-15T02:52:49+00:00

Add tests for non-number character, empty regions, integer overflow.

[ynorov@marvell.com: v5]
  Link: http://lkml.kernel.org/r/20190416063801.20134-5-ynorov@marvell.com
Link: http://lkml.kernel.org/r/20190405173211.11373-5-ynorov@marvell.com
Signed-off-by: Yury Norov 
Reviewed-by: Andy Shevchenko 
Cc: Arnd Bergmann 
Cc: Kees Cook 
Cc: Matthew Wilcox 
Cc: Mike Travis 
Cc: Rasmus Villemoes 
Cc: Tetsuo Handa 
Cc: Guenter Roeck 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/test_bitmap: switch test_bitmap_parselist to ktime_get()

2019-05-15T02:52:49+00:00

test_bitmap_parselist currently uses get_cycles which is not implemented
on some platforms, so use ktime_get() instead.

Link: http://lkml.kernel.org/r/20190405173211.11373-4-ynorov@marvell.com
Signed-off-by: Yury Norov 
Reviewed-by: Andy Shevchenko 
Cc: Arnd Bergmann 
Cc: Kees Cook 
Cc: Matthew Wilcox 
Cc: Mike Travis 
Cc: Rasmus Villemoes 
Cc: Tetsuo Handa 
Cc: Guenter Roeck 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: rework bitmap_parselist

2019-05-15T02:52:49+00:00

Remove __bitmap_parselist helper and split the function to logical
parts.

[ynorov@marvell.com: v5]
  Link: http://lkml.kernel.org/r/20190416063801.20134-3-ynorov@marvell.com
Link: http://lkml.kernel.org/r/20190405173211.11373-3-ynorov@marvell.com
Signed-off-by: Yury Norov 
Reviewed-by: Andy Shevchenko 
Cc: Arnd Bergmann 
Cc: Kees Cook 
Cc: Matthew Wilcox 
Cc: Mike Travis 
Cc: Rasmus Villemoes 
Cc: Tetsuo Handa 
Cc: Guenter Roeck 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds