linux-stable.git/drivers/misc/lkdtm, branch linux-5.4.y

locking/refcount: Define constants for saturation and max refcount values

2022-07-29T15:14:16+00:00

[ Upstream commit 23e6b169c9917fbd77534f8c5f378cb073f548bd ]

The REFCOUNT_FULL implementation uses a different saturation point than
the x86 implementation, which means that the shared refcount code in
lib/refcount.c (e.g. refcount_dec_not_one()) needs to be aware of the
difference.

Rather than duplicate the definitions from the lkdtm driver, instead
move them into  and update all references accordingly.

Signed-off-by: Will Deacon 
Reviewed-by: Ard Biesheuvel 
Reviewed-by: Kees Cook 
Tested-by: Hanjun Guo 
Cc: Ard Biesheuvel 
Cc: Elena Reshetova 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: https://lkml.kernel.org/r/20191121115902.2551-2-will@kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

lkdtm/usercopy: Expand size of "out of frame" object

2022-06-14T16:11:59+00:00

[ Upstream commit f387e86d3a74407bdd9c5815820ac9d060962840 ]

To be sufficiently out of range for the usercopy test to see the lifetime
mismatch, expand the size of the "bad" buffer, which will let it be
beyond current_stack_pointer regardless of stack growth direction.
Paired with the recent addition of stack depth checking under
CONFIG_HARDENED_USERCOPY=y, this will correctly start tripping again.

Reported-by: Muhammad Usama Anjum 
Cc: Arnd Bergmann 
Cc: Greg Kroah-Hartman 
Reviewed-by: Muhammad Usama Anjum 
Link: https://lore.kernel.org/lkml/762faf1b-0443-5ddf-4430-44a20cf2ec4d@collabora.com/
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin

lkdtm: Fix content of section containing lkdtm_rodata_do_nothing()

2022-01-27T08:19:28+00:00

commit bc93a22a19eb2b68a16ecf04cdf4b2ed65aaf398 upstream.

On a kernel without CONFIG_STRICT_KERNEL_RWX, running EXEC_RODATA
test leads to "Illegal instruction" failure.

Looking at the content of rodata_objcopy.o, we see that the
function content zeroes only:

	Disassembly of section .rodata:

	0000000000000000 <.lkdtm_rodata_do_nothing>:
	   0:	00 00 00 00 	.long 0x0

Add the contents flag in order to keep the content of the section
while renaming it.

	Disassembly of section .rodata:

	0000000000000000 <.lkdtm_rodata_do_nothing>:
	   0:	4e 80 00 20 	blr

Fixes: e9e08a07385e ("lkdtm: support llvm-objcopy")
Cc: stable@vger.kernel.org
Cc: Kees Cook 
Cc: Arnd Bergmann 
Cc: Greg Kroah-Hartman 
Cc: Nick Desaulniers 
Cc: Nathan Chancellor 
Signed-off-by: Christophe Leroy 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/8900731fbc05fb8b0de18af7133a8fc07c3c53a1.1633712176.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman

lkdtm: don't move ctors to .rodata

2021-02-17T09:35:16+00:00

[ Upstream commit 3f618ab3323407ee4c6a6734a37eb6e9663ebfb9 ]

When building with KASAN and LKDTM, clang may implictly generate an
asan.module_ctor function in the LKDTM rodata object. The Makefile moves
the lkdtm_rodata_do_nothing() function into .rodata by renaming the
file's .text section to .rodata, and consequently also moves the ctor
function into .rodata, leading to a boot time crash (splat below) when
the ctor is invoked by do_ctors().

Let's prevent this by marking the function as noinstr rather than
notrace, and renaming the file's .noinstr.text to .rodata. Marking the
function as noinstr will prevent tracing and kprobes, and will inhibit
any undesireable compiler instrumentation.

The ctor function (if any) will be placed in .text and will work
correctly.

Example splat before this patch is applied:

[    0.916359] Unable to handle kernel execute from non-executable memory at virtual address ffffa0006b60f5ac
[    0.922088] Mem abort info:
[    0.922828]   ESR = 0x8600000e
[    0.923635]   EC = 0x21: IABT (current EL), IL = 32 bits
[    0.925036]   SET = 0, FnV = 0
[    0.925838]   EA = 0, S1PTW = 0
[    0.926714] swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000427b3000
[    0.928489] [ffffa0006b60f5ac] pgd=000000023ffff003, p4d=000000023ffff003, pud=000000023fffe003, pmd=0068000042000f01
[    0.931330] Internal error: Oops: 8600000e [#1] PREEMPT SMP
[    0.932806] Modules linked in:
[    0.933617] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc7 #2
[    0.935620] Hardware name: linux,dummy-virt (DT)
[    0.936924] pstate: 40400005 (nZcv daif +PAN -UAO -TCO BTYPE=--)
[    0.938609] pc : asan.module_ctor+0x0/0x14
[    0.939759] lr : do_basic_setup+0x4c/0x70
[    0.940889] sp : ffff27b600177e30
[    0.941815] x29: ffff27b600177e30 x28: 0000000000000000
[    0.943306] x27: 0000000000000000 x26: 0000000000000000
[    0.944803] x25: 0000000000000000 x24: 0000000000000000
[    0.946289] x23: 0000000000000001 x22: 0000000000000000
[    0.947777] x21: ffffa0006bf4a890 x20: ffffa0006befb6c0
[    0.949271] x19: ffffa0006bef9358 x18: 0000000000000068
[    0.950756] x17: fffffffffffffff8 x16: 0000000000000000
[    0.952246] x15: 0000000000000000 x14: 0000000000000000
[    0.953734] x13: 00000000838a16d5 x12: 0000000000000001
[    0.955223] x11: ffff94000da74041 x10: dfffa00000000000
[    0.956715] x9 : 0000000000000000 x8 : ffffa0006b60f5ac
[    0.958199] x7 : f9f9f9f9f9f9f9f9 x6 : 000000000000003f
[    0.959683] x5 : 0000000000000040 x4 : 0000000000000000
[    0.961178] x3 : ffffa0006bdc15a0 x2 : 0000000000000005
[    0.962662] x1 : 00000000000000f9 x0 : ffffa0006bef9350
[    0.964155] Call trace:
[    0.964844]  asan.module_ctor+0x0/0x14
[    0.965895]  kernel_init_freeable+0x158/0x198
[    0.967115]  kernel_init+0x14/0x19c
[    0.968104]  ret_from_fork+0x10/0x30
[    0.969110] Code: 00000003 00000000 00000000 00000000 (00000000)
[    0.970815] ---[ end trace b5339784e20d015c ]---

Cc: Arnd Bergmann 
Cc: Greg Kroah-Hartman 
Cc: Kees Cook 
Acked-by: Kees Cook 
Signed-off-by: Mark Rutland 
Link: https://lore.kernel.org/r/20201207170533.10738-1-mark.rutland@arm.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

lkdtm/bugs: fix build error in lkdtm_UNSET_SMEP

2020-02-05T21:22:46+00:00

[ Upstream commit 0e31e3573f0cd94d7b821117db854187ffc85765 ]

When building ARCH=um with CONFIG_UML_X86=y and CONFIG_64BIT=y we get
the build errors:

drivers/misc/lkdtm/bugs.c: In function ‘lkdtm_UNSET_SMEP’:
drivers/misc/lkdtm/bugs.c:288:8: error: implicit declaration of function ‘native_read_cr4’ [-Werror=implicit-function-declaration]
  cr4 = native_read_cr4();
        ^~~~~~~~~~~~~~~
drivers/misc/lkdtm/bugs.c:290:13: error: ‘X86_CR4_SMEP’ undeclared (first use in this function); did you mean ‘X86_FEATURE_SMEP’?
  if ((cr4 & X86_CR4_SMEP) != X86_CR4_SMEP) {
             ^~~~~~~~~~~~
             X86_FEATURE_SMEP
drivers/misc/lkdtm/bugs.c:290:13: note: each undeclared identifier is reported only once for each function it appears in
drivers/misc/lkdtm/bugs.c:297:2: error: implicit declaration of function ‘native_write_cr4’; did you mean ‘direct_write_cr4’? [-Werror=implicit-function-declaration]
  native_write_cr4(cr4);
  ^~~~~~~~~~~~~~~~
  direct_write_cr4

So specify that this block of code should only build when
CONFIG_X86_64=y *AND* CONFIG_UML is unset.

Signed-off-by: Brendan Higgins 
Acked-by: Kees Cook 
Link: https://lore.kernel.org/r/20191213003522.66450-1-brendanhiggins@google.com
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

Merge 5.3-rc7 into char-misc-next

2019-09-02T17:30:09+00:00

We need the fixes in here as well for testing and merges

Signed-off-by: Greg Kroah-Hartman

lkdtm/bugs: fix build error in lkdtm_EXHAUST_STACK

2019-08-28T20:33:44+00:00

lkdtm/bugs.c:94:2: error: format '%d' expects argument of type 'int', but argument 2 has type 'long unsigned int' [-Werror=format=]
  pr_info("Calling function with %d frame size to depth %d ...\n",
  ^
THREAD_SIZE is defined as a unsigned long, cast CONFIG_FRAME_WARN to
unsigned long as well.

Fixes: 24cccab42c419 ("lkdtm/bugs: Adjust recursion test to avoid elision")
Cc: stable 
Signed-off-by: Raul E Rangel 
Acked-by: Kees Cook 
Link: https://lore.kernel.org/r/20190827173619.170065-1-rrangel@chromium.org
Signed-off-by: Greg Kroah-Hartman

lkdtm: Split WARNING into separate tests

2019-08-19T18:13:21+00:00

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

lkdtm: Add Control Flow Integrity test

2019-08-12T22:28:51+00:00

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

Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2019-07-12T19:24:03+00:00

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...