Граф коммитов

11 Коммитов

Автор SHA1 Сообщение Дата
Kees Cook 1ee170ea3f lkdtm: Split WARNING into separate tests
There are three paths through the kernel code exception logging:

- BUG (no configurable printk message)
- WARN_ON (no configurable printk message)
- WARN (configurable printk message)

LKDTM was not testing WARN_ON(). This is needed to evaluate the placement
of the "cut here" line, which needs special handling in each of the
three exceptions (and between architectures that implement instruction
exceptions to implement the code exceptions).

Signed-off-by: Kees Cook <keescook@chromium.org>
2019-08-19 11:13:21 -07:00
Kees Cook b0eb93cfd5 lkdtm: Add Control Flow Integrity test
This adds a simple test for forward CFI (indirect function calls) with
function prototype granularity (as implemented by Clang's CFI).

Signed-off-by: Kees Cook <keescook@chromium.org>
2019-08-12 15:28:51 -07:00
Linus Torvalds ef8f3d48af Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
 "Am experimenting with splitting MM up into identifiable subsystems
  perhaps with a view to gitifying it in complex ways. Also with more
  verbose "incoming" emails.

  Most of MM is here and a few other trees.

  Subsystems affected by this patch series:
   - hotfixes
   - iommu
   - scripts
   - arch/sh
   - ocfs2
   - mm:slab-generic
   - mm:slub
   - mm:kmemleak
   - mm:kasan
   - mm:cleanups
   - mm:debug
   - mm:pagecache
   - mm:swap
   - mm:memcg
   - mm:gup
   - mm:pagemap
   - mm:infrastructure
   - mm:vmalloc
   - mm:initialization
   - mm:pagealloc
   - mm:vmscan
   - mm:tools
   - mm:proc
   - mm:ras
   - mm:oom-kill

  hotfixes:
      mm: vmscan: scan anonymous pages on file refaults
      mm/nvdimm: add is_ioremap_addr and use that to check ioremap address
      mm/memcontrol: fix wrong statistics in memory.stat
      mm/z3fold.c: lock z3fold page before  __SetPageMovable()
      nilfs2: do not use unexported cpu_to_le32()/le32_to_cpu() in uapi header
      MAINTAINERS: nilfs2: update email address

  iommu:
      include/linux/dmar.h: replace single-char identifiers in macros

  scripts:
      scripts/decode_stacktrace: match basepath using shell prefix operator, not regex
      scripts/decode_stacktrace: look for modules with .ko.debug extension
      scripts/spelling.txt: drop "sepc" from the misspelling list
      scripts/spelling.txt: add spelling fix for prohibited
      scripts/decode_stacktrace: Accept dash/underscore in modules
      scripts/spelling.txt: add more spellings to spelling.txt

  arch/sh:
      arch/sh/configs/sdk7786_defconfig: remove CONFIG_LOGFS
      sh: config: remove left-over BACKLIGHT_LCD_SUPPORT
      sh: prevent warnings when using iounmap

  ocfs2:
      fs: ocfs: fix spelling mistake "hearbeating" -> "heartbeat"
      ocfs2/dlm: use struct_size() helper
      ocfs2: add last unlock times in locking_state
      ocfs2: add locking filter debugfs file
      ocfs2: add first lock wait time in locking_state
      ocfs: no need to check return value of debugfs_create functions
      fs/ocfs2/dlmglue.c: unneeded variable: "status"
      ocfs2: use kmemdup rather than duplicating its implementation

  mm:slab-generic:
    Patch series "mm/slab: Improved sanity checking":
      mm/slab: validate cache membership under freelist hardening
      mm/slab: sanity-check page type when looking up cache
      lkdtm/heap: add tests for freelist hardening

  mm:slub:
      mm/slub.c: avoid double string traverse in kmem_cache_flags()
      slub: don't panic for memcg kmem cache creation failure

  mm:kmemleak:
      mm/kmemleak.c: fix check for softirq context
      mm/kmemleak.c: change error at _write when kmemleak is disabled
      docs: kmemleak: add more documentation details

  mm:kasan:
      mm/kasan: print frame description for stack bugs
      Patch series "Bitops instrumentation for KASAN", v5:
        lib/test_kasan: add bitops tests
        x86: use static_cpu_has in uaccess region to avoid instrumentation
        asm-generic, x86: add bitops instrumentation for KASAN
      Patch series "mm/kasan: Add object validation in ksize()", v3:
        mm/kasan: introduce __kasan_check_{read,write}
        mm/kasan: change kasan_check_{read,write} to return boolean
        lib/test_kasan: Add test for double-kzfree detection
        mm/slab: refactor common ksize KASAN logic into slab_common.c
        mm/kasan: add object validation in ksize()

  mm:cleanups:
      include/linux/pfn_t.h: remove pfn_t_to_virt()
      Patch series "remove ARCH_SELECT_MEMORY_MODEL where it has no effect":
        arm: remove ARCH_SELECT_MEMORY_MODEL
        s390: remove ARCH_SELECT_MEMORY_MODEL
        sparc: remove ARCH_SELECT_MEMORY_MODEL
      mm/gup.c: make follow_page_mask() static
      mm/memory.c: trivial clean up in insert_page()
      mm: make !CONFIG_HUGE_PAGE wrappers into static inlines
      include/linux/mm_types.h: ifdef struct vm_area_struct::swap_readahead_info
      mm: remove the account_page_dirtied export
      mm/page_isolation.c: change the prototype of undo_isolate_page_range()
      include/linux/vmpressure.h: use spinlock_t instead of struct spinlock
      mm: remove the exporting of totalram_pages
      include/linux/pagemap.h: document trylock_page() return value

  mm:debug:
      mm/failslab.c: by default, do not fail allocations with direct reclaim only
      Patch series "debug_pagealloc improvements":
        mm, debug_pagelloc: use static keys to enable debugging
        mm, page_alloc: more extensive free page checking with debug_pagealloc
        mm, debug_pagealloc: use a page type instead of page_ext flag

  mm:pagecache:
      Patch series "fix filler_t callback type mismatches", v2:
        mm/filemap.c: fix an overly long line in read_cache_page
        mm/filemap: don't cast ->readpage to filler_t for do_read_cache_page
        jffs2: pass the correct prototype to read_cache_page
        9p: pass the correct prototype to read_cache_page
      mm/filemap.c: correct the comment about VM_FAULT_RETRY

  mm:swap:
      mm, swap: fix race between swapoff and some swap operations
      mm/swap_state.c: simplify total_swapcache_pages() with get_swap_device()
      mm, swap: use rbtree for swap_extent
      mm/mincore.c: fix race between swapoff and mincore

  mm:memcg:
      memcg, oom: no oom-kill for __GFP_RETRY_MAYFAIL
      memcg, fsnotify: no oom-kill for remote memcg charging
      mm, memcg: introduce memory.events.local
      mm: memcontrol: dump memory.stat during cgroup OOM
      Patch series "mm: reparent slab memory on cgroup removal", v7:
        mm: memcg/slab: postpone kmem_cache memcg pointer initialization to memcg_link_cache()
        mm: memcg/slab: rename slab delayed deactivation functions and fields
        mm: memcg/slab: generalize postponed non-root kmem_cache deactivation
        mm: memcg/slab: introduce __memcg_kmem_uncharge_memcg()
        mm: memcg/slab: unify SLAB and SLUB page accounting
        mm: memcg/slab: don't check the dying flag on kmem_cache creation
        mm: memcg/slab: synchronize access to kmem_cache dying flag using a spinlock
        mm: memcg/slab: rework non-root kmem_cache lifecycle management
        mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages
        mm: memcg/slab: reparent memcg kmem_caches on cgroup removal
      mm, memcg: add a memcg_slabinfo debugfs file

  mm:gup:
      Patch series "switch the remaining architectures to use generic GUP", v4:
        mm: use untagged_addr() for get_user_pages_fast addresses
        mm: simplify gup_fast_permitted
        mm: lift the x86_32 PAE version of gup_get_pte to common code
        MIPS: use the generic get_user_pages_fast code
        sh: add the missing pud_page definition
        sh: use the generic get_user_pages_fast code
        sparc64: add the missing pgd_page definition
        sparc64: define untagged_addr()
        sparc64: use the generic get_user_pages_fast code
        mm: rename CONFIG_HAVE_GENERIC_GUP to CONFIG_HAVE_FAST_GUP
        mm: reorder code blocks in gup.c
        mm: consolidate the get_user_pages* implementations
        mm: validate get_user_pages_fast flags
        mm: move the powerpc hugepd code to mm/gup.c
        mm: switch gup_hugepte to use try_get_compound_head
        mm: mark the page referenced in gup_hugepte
      mm/gup: speed up check_and_migrate_cma_pages() on huge page
      mm/gup.c: remove some BUG_ONs from get_gate_page()
      mm/gup.c: mark undo_dev_pagemap as __maybe_unused

  mm:pagemap:
      asm-generic, x86: introduce generic pte_{alloc,free}_one[_kernel]
      alpha: switch to generic version of pte allocation
      arm: switch to generic version of pte allocation
      arm64: switch to generic version of pte allocation
      csky: switch to generic version of pte allocation
      m68k: sun3: switch to generic version of pte allocation
      mips: switch to generic version of pte allocation
      nds32: switch to generic version of pte allocation
      nios2: switch to generic version of pte allocation
      parisc: switch to generic version of pte allocation
      riscv: switch to generic version of pte allocation
      um: switch to generic version of pte allocation
      unicore32: switch to generic version of pte allocation
      mm/pgtable: drop pgtable_t variable from pte_fn_t functions
      mm/memory.c: fail when offset == num in first check of __vm_map_pages()

  mm:infrastructure:
      mm/mmu_notifier: use hlist_add_head_rcu()

  mm:vmalloc:
      Patch series "Some cleanups for the KVA/vmalloc", v5:
        mm/vmalloc.c: remove "node" argument
        mm/vmalloc.c: preload a CPU with one object for split purpose
        mm/vmalloc.c: get rid of one single unlink_va() when merge
        mm/vmalloc.c: switch to WARN_ON() and move it under unlink_va()
      mm/vmalloc.c: spelling> s/informaion/information/

  mm:initialization:
      mm/large system hash: use vmalloc for size > MAX_ORDER when !hashdist
      mm/large system hash: clear hashdist when only one node with memory is booted

  mm:pagealloc:
      arm64: move jump_label_init() before parse_early_param()
      Patch series "add init_on_alloc/init_on_free boot options", v10:
        mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options
        mm: init: report memory auto-initialization features at boot time

  mm:vmscan:
      mm: vmscan: remove double slab pressure by inc'ing sc->nr_scanned
      mm: vmscan: correct some vmscan counters for THP swapout

  mm:tools:
      tools/vm/slabinfo: order command line options
      tools/vm/slabinfo: add partial slab listing to -X
      tools/vm/slabinfo: add option to sort by partial slabs
      tools/vm/slabinfo: add sorting info to help menu

  mm:proc:
      proc: use down_read_killable mmap_sem for /proc/pid/maps
      proc: use down_read_killable mmap_sem for /proc/pid/smaps_rollup
      proc: use down_read_killable mmap_sem for /proc/pid/pagemap
      proc: use down_read_killable mmap_sem for /proc/pid/clear_refs
      proc: use down_read_killable mmap_sem for /proc/pid/map_files
      mm: use down_read_killable for locking mmap_sem in access_remote_vm
      mm: smaps: split PSS into components
      mm: vmalloc: show number of vmalloc pages in /proc/meminfo

  mm:ras:
      mm/memory-failure.c: clarify error message

  mm:oom-kill:
      mm: memcontrol: use CSS_TASK_ITER_PROCS at mem_cgroup_scan_tasks()
      mm, oom: refactor dump_tasks for memcg OOMs
      mm, oom: remove redundant task_in_mem_cgroup() check
      oom: decouple mems_allowed from oom_unkillable_task
      mm/oom_kill.c: remove redundant OOM score normalization in select_bad_process()"

* akpm: (147 commits)
  mm/oom_kill.c: remove redundant OOM score normalization in select_bad_process()
  oom: decouple mems_allowed from oom_unkillable_task
  mm, oom: remove redundant task_in_mem_cgroup() check
  mm, oom: refactor dump_tasks for memcg OOMs
  mm: memcontrol: use CSS_TASK_ITER_PROCS at mem_cgroup_scan_tasks()
  mm/memory-failure.c: clarify error message
  mm: vmalloc: show number of vmalloc pages in /proc/meminfo
  mm: smaps: split PSS into components
  mm: use down_read_killable for locking mmap_sem in access_remote_vm
  proc: use down_read_killable mmap_sem for /proc/pid/map_files
  proc: use down_read_killable mmap_sem for /proc/pid/clear_refs
  proc: use down_read_killable mmap_sem for /proc/pid/pagemap
  proc: use down_read_killable mmap_sem for /proc/pid/smaps_rollup
  proc: use down_read_killable mmap_sem for /proc/pid/maps
  tools/vm/slabinfo: add sorting info to help menu
  tools/vm/slabinfo: add option to sort by partial slabs
  tools/vm/slabinfo: add partial slab listing to -X
  tools/vm/slabinfo: order command line options
  mm: vmscan: correct some vmscan counters for THP swapout
  mm: vmscan: remove double slab pressure by inc'ing sc->nr_scanned
  ...
2019-07-12 11:40:28 -07:00
Kees Cook 966fede8e4 lkdtm/heap: add tests for freelist hardening
This adds tests for double free and cross-cache freeing, which should both
be caught by CONFIG_SLAB_FREELIST_HARDENED.

Link: http://lkml.kernel.org/r/20190530045017.15252-4-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Popov <alex.popov@linux.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-12 11:05:41 -07:00
Kees Cook 06b32fdb03 lkdtm: Check for SMEP clearing protections
This adds an x86-specific test for pinned cr4 bits. A successful test
will validate pinning and check the ROP-style call-middle-of-function
defense, if needed. For example, in the case of native_write_cr4()
looking like this:

ffffffff8171bce0 <native_write_cr4>:
ffffffff8171bce0:       48 8b 35 79 46 f2 00    mov    0xf24679(%rip),%rsi
ffffffff8171bce7:       48 09 f7                or     %rsi,%rdi
ffffffff8171bcea:       0f 22 e7                mov    %rdi,%cr4
...
ffffffff8171bd5a:       c3                      retq

The UNSET_SMEP test will jump to ffffffff8171bcea (the mov to cr4)
instead of ffffffff8171bce0 (native_write_cr4() entry) to simulate a
direct-call bypass attempt.

Expected successful results:

  # echo UNSET_SMEP > /sys/kernel/debug/provoke-crash/DIRECT
  # dmesg
  [   79.594433] lkdtm: Performing direct entry UNSET_SMEP
  [   79.596459] lkdtm: trying to clear SMEP normally
  [   79.598406] lkdtm: ok: SMEP did not get cleared
  [   79.599981] lkdtm: trying to clear SMEP with call gadget
  [   79.601810] ------------[ cut here ]------------
  [   79.603421] Attempt to unpin cr4 bits: 100000; bypass attack?!
  ...
  [   79.650170] ---[ end trace 2452ca0f6126242e ]---
  [   79.650937] lkdtm: ok: SMEP removal was reverted

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-23 07:05:56 +02:00
Kees Cook 24cccab42c lkdtm/bugs: Adjust recursion test to avoid elision
While I was able to trick gcc into keeping a pathological recursion,
Clang was not so easily fooled. Instead, switch to using "volatile" and
side-effects to keep the stack variable allocated and to run the function.
Additionally renames "OVERFLOW" to "EXHAUST_STACK" to better describe the
test.

Signed-off-by: Kees Cook <keescook@chromium.org>
2019-04-07 10:38:31 -07:00
Christophe Leroy 59a12205d3 lkdtm: Add tests for NULL pointer dereference
Introduce lkdtm tests for NULL pointer dereference: check access or exec
at NULL address, since these errors tend to be reported differently from
the general fault error text. For example from x86:

    pr_alert("BUG: unable to handle kernel %s at %px\n",
        address < PAGE_SIZE ? "NULL pointer dereference" : "paging request",
        (void *)address);

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Kees Cook <keescook@chromium.org>
2019-01-09 12:00:31 -08:00
Linus Torvalds 2d6bb6adb7 New gcc plugin: stackleak
- Introduces the stackleak gcc plugin ported from grsecurity by Alexander
   Popov, with x86 and arm64 support.
 -----BEGIN PGP SIGNATURE-----
 Comment: Kees Cook <kees@outflux.net>
 
 iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAlvQvn4WHGtlZXNjb29r
 QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJpSfD/sErFreuPT1beSw994Lr9Zx4k9v
 ERsuXxWBENaJOJXbOOHMfVEcEeG/1uhPSp7hlw/dpHfh0anATTrcYqm8RNKbfK+k
 o06+JK14OJfpm5Ghq/7OizhdNLCMT8wMU3XZtWfy65VSJGjEFx8Y48vMeQtpWtUK
 ylSzi9JV6j2iUBF9oibtiT53+yqsqAtX80X1G7HRCgv9kxuKMhZr+Q5oGV6+ViyQ
 Azj8mNn06iRnhHKd17WxDJr0GjSibzz4weS/9XgP3t3EcNWJo1EgBlD2KV3tOfP5
 nzmqfqTqrcjxs/tyjdh6vVCSlYucNtyCQGn63qyShQYSg6mZwclR2fY8YSTw6PWw
 GfYWFOWru9z+qyQmwFkQ9bSQS2R+JIT0oBCj9VmtF9XmPCy7K2neJsQclzSPBiCW
 wPgXVQS4IA4684O5CmDOVMwmDpGvhdBNUR6cqSzGLxQOHY1csyXubMNUsqU3g9xk
 Ob4pEy/xrrIw4WpwHcLHSEW5gV1/OLhsT0fGRJJiC947L3cN5s9EZp7FLbIS0zlk
 qzaXUcLmn6AgcfkYwg5cI3RMLaN2V0eDCMVTWZJ1wbrmUV9chAaOnTPTjNqLOTht
 v3b1TTxXG4iCpMmOFf59F8pqgAwbBDlfyNSbySZ/Pq5QH69udz3Z9pIUlYQnSJHk
 u6q++2ReDpJXF81rBw==
 =Ks6B
 -----END PGP SIGNATURE-----

Merge tag 'stackleak-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull stackleak gcc plugin from Kees Cook:
 "Please pull this new GCC plugin, stackleak, for v4.20-rc1. This plugin
  was ported from grsecurity by Alexander Popov. It provides efficient
  stack content poisoning at syscall exit. This creates a defense
  against at least two classes of flaws:

   - Uninitialized stack usage. (We continue to work on improving the
     compiler to do this in other ways: e.g. unconditional zero init was
     proposed to GCC and Clang, and more plugin work has started too).

   - Stack content exposure. By greatly reducing the lifetime of valid
     stack contents, exposures via either direct read bugs or unknown
     cache side-channels become much more difficult to exploit. This
     complements the existing buddy and heap poisoning options, but
     provides the coverage for stacks.

  The x86 hooks are included in this series (which have been reviewed by
  Ingo, Dave Hansen, and Thomas Gleixner). The arm64 hooks have already
  been merged through the arm64 tree (written by Laura Abbott and
  reviewed by Mark Rutland and Will Deacon).

  With VLAs having been removed this release, there is no need for
  alloca() protection, so it has been removed from the plugin"

* tag 'stackleak-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  arm64: Drop unneeded stackleak_check_alloca()
  stackleak: Allow runtime disabling of kernel stack erasing
  doc: self-protection: Add information about STACKLEAK feature
  fs/proc: Show STACKLEAK metrics in the /proc file system
  lkdtm: Add a test for STACKLEAK
  gcc-plugins: Add STACKLEAK plugin for tracking the kernel stack
  x86/entry: Add STACKLEAK erasing the kernel stack at the end of syscalls
2018-11-01 11:46:27 -07:00
Alexander Popov f90d1e0c78 lkdtm: Add a test for STACKLEAK
Introduce an lkdtm test for the STACKLEAK feature: check that the
current task stack is properly erased (filled with STACKLEAK_POISON).

Signed-off-by: Alexander Popov <alex.popov@linux.com>
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-09-04 10:35:47 -07:00
Jann Horn bef459026b lkdtm: Test copy_to_user() on bad kernel pointer under KERNEL_DS
Test whether the kernel WARN()s when, under KERNEL_DS, a bad kernel pointer
is used as "userspace" pointer. Should normally be used in "DIRECT" mode.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: dvyukov@google.com
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/20180828201421.157735-8-jannh@google.com
2018-09-03 15:12:10 +02:00
Kees Cook 039a1c4205 lkdtm: Relocate code to subdirectory
The LKDTM modules keep expanding, and it's getting weird to have each file
get a prefix. Instead, move to a subdirectory for cleaner handling.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06 19:18:55 -08:00