Commit Graph

80 Commits

Author SHA1 Message Date
Marco Elver 2db710cc84 kasan: fix build by including kernel.h
The <linux/kasan.h> header relies on _RET_IP_ being defined, and had been
receiving that definition via inclusion of bug.h which includes kernel.h.
However, since f39650de68 ("kernel.h: split out panic and oops helpers")
that is no longer the case and get the following build error when building
CONFIG_KASAN_HW_TAGS on arm64:

  In file included from arch/arm64/mm/kasan_init.c:10:
  include/linux/kasan.h: In function 'kasan_slab_free':
  include/linux/kasan.h:230:39: error: '_RET_IP_' undeclared (first use in this function)
    230 |   return __kasan_slab_free(s, object, _RET_IP_, init);

Fix it by including kernel.h from kasan.h.

Link: https://lkml.kernel.org/r/20210705072716.2125074-1-elver@google.com
Fixes: f39650de68 ("kernel.h: split out panic and oops helpers")
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-15 10:13:49 -07:00
Linus Torvalds 65090f30ab Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "191 patches.

  Subsystems affected by this patch series: kthread, ia64, scripts,
  ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab,
  slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap,
  mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization,
  pagealloc, and memory-failure)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits)
  mm,hwpoison: make get_hwpoison_page() call get_any_page()
  mm,hwpoison: send SIGBUS with error virutal address
  mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes
  mm/page_alloc: allow high-order pages to be stored on the per-cpu lists
  mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM
  mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA
  docs: remove description of DISCONTIGMEM
  arch, mm: remove stale mentions of DISCONIGMEM
  mm: remove CONFIG_DISCONTIGMEM
  m68k: remove support for DISCONTIGMEM
  arc: remove support for DISCONTIGMEM
  arc: update comment about HIGHMEM implementation
  alpha: remove DISCONTIGMEM and NUMA
  mm/page_alloc: move free_the_page
  mm/page_alloc: fix counting of managed_pages
  mm/page_alloc: improve memmap_pages dbg msg
  mm: drop SECTION_SHIFT in code comments
  mm/page_alloc: introduce vm.percpu_pagelist_high_fraction
  mm/page_alloc: limit the number of pages on PCP lists when reclaim is active
  mm/page_alloc: scale the number of pages that are batch freed
  ...
2021-06-29 17:29:11 -07:00
Daniel Axtens cb32c9c5d4 kasan: use MAX_PTRS_PER_* for early shadow tables
powerpc has a variable number of PTRS_PER_*, set at runtime based on the
MMU that the kernel is booted under.

This means the PTRS_PER_* are no longer constants, and therefore breaks
the build.  Switch to using MAX_PTRS_PER_*, which are constant.

Link: https://lkml.kernel.org/r/20210624034050.511391-5-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Suggested-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:53 -07:00
David Gow 3ff16d30f5 kasan: test: improve failure message in KUNIT_EXPECT_KASAN_FAIL()
The KUNIT_EXPECT_KASAN_FAIL() macro currently uses KUNIT_EXPECT_EQ() to
compare fail_data.report_expected and fail_data.report_found.  This always
gave a somewhat useless error message on failure, but the addition of
extra compile-time checking with READ_ONCE() has caused it to get much
longer, and be truncated before anything useful is displayed.

Instead, just check fail_data.report_found by hand (we've just set
report_expected to 'true'), and print a better failure message with
KUNIT_FAIL().  Because of this, report_expected is no longer used
anywhere, and can be removed.

Beforehand, a failure in:
KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)area)[3100]);
would have looked like:
[22:00:34] [FAILED] vmalloc_oob
[22:00:34]     # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:991
[22:00:34]     Expected ({ do { extern void __compiletime_assert_705(void) __attribute__((__error__("Unsupported access size for {READ,WRITE}_ONCE()."))); if (!((sizeof(fail_data.report_expected) == sizeof(char) || sizeof(fail_data.repp
[22:00:34]     not ok 45 - vmalloc_oob

With this change, it instead looks like:
[22:04:04] [FAILED] vmalloc_oob
[22:04:04]     # vmalloc_oob: EXPECTATION FAILED at lib/test_kasan.c:993
[22:04:04]     KASAN failure expected in "((volatile char *)area)[3100]", but none occurred
[22:04:04]     not ok 45 - vmalloc_oob

Also update the example failure in the documentation to reflect this.

Link: https://lkml.kernel.org/r/20210606005531.165954-1-davidgow@google.com
Signed-off-by: David Gow <davidgow@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: David Gow <davidgow@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:52 -07:00
Peter Collingbourne 7a3b835371 kasan: use separate (un)poison implementation for integrated init
Currently with integrated init page_alloc.c needs to know whether
kasan_alloc_pages() will zero initialize memory, but this will start
becoming more complicated once we start adding tag initialization
support for user pages. To avoid page_alloc.c needing to know more
details of what integrated init will do, move the unpoisoning logic
for integrated init into the HW tags implementation. Currently the
logic is identical but it will diverge in subsequent patches.

For symmetry do the same for poisoning although this logic will
be unaffected by subsequent patches.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://linux-review.googlesource.com/id/I2c550234c6c4a893c48c18ff0c6ce658c7c67056
Link: https://lore.kernel.org/r/20210602235230.3928842-3-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-04 19:32:21 +01:00
Andrey Konovalov d57a964e09 kasan, mm: integrate slab init_on_free with HW_TAGS
This change uses the previously added memory initialization feature of
HW_TAGS KASAN routines for slab memory when init_on_free is enabled.

With this change, memory initialization memset() is no longer called when
both HW_TAGS KASAN and init_on_free are enabled.  Instead, memory is
initialized in KASAN runtime.

For SLUB, the memory initialization memset() is moved into
slab_free_hook() that currently directly follows the initialization loop.
A new argument is added to slab_free_hook() that indicates whether to
initialize the memory or not.

To avoid discrepancies with which memory gets initialized that can be
caused by future changes, both KASAN hook and initialization memset() are
put together and a warning comment is added.

Combining setting allocation tags with memory initialization improves
HW_TAGS KASAN performance when init_on_free is enabled.

Link: https://lkml.kernel.org/r/190fd15c1886654afdec0d19ebebd5ade665b601.1615296150.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:41 -07:00
Andrey Konovalov da844b7872 kasan, mm: integrate slab init_on_alloc with HW_TAGS
This change uses the previously added memory initialization feature of
HW_TAGS KASAN routines for slab memory when init_on_alloc is enabled.

With this change, memory initialization memset() is no longer called when
both HW_TAGS KASAN and init_on_alloc are enabled.  Instead, memory is
initialized in KASAN runtime.

The memory initialization memset() is moved into slab_post_alloc_hook()
that currently directly follows the initialization loop.  A new argument
is added to slab_post_alloc_hook() that indicates whether to initialize
the memory or not.

To avoid discrepancies with which memory gets initialized that can be
caused by future changes, both KASAN hook and initialization memset() are
put together and a warning comment is added.

Combining setting allocation tags with memory initialization improves
HW_TAGS KASAN performance when init_on_alloc is enabled.

Link: https://lkml.kernel.org/r/c1292aeb5d519da221ec74a0684a949b027d7720.1615296150.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:41 -07:00
Andrey Konovalov 1bb5eab30d kasan, mm: integrate page_alloc init with HW_TAGS
This change uses the previously added memory initialization feature of
HW_TAGS KASAN routines for page_alloc memory when init_on_alloc/free is
enabled.

With this change, kernel_init_free_pages() is no longer called when both
HW_TAGS KASAN and init_on_alloc/free are enabled.  Instead, memory is
initialized in KASAN runtime.

To avoid discrepancies with which memory gets initialized that can be
caused by future changes, both KASAN and kernel_init_free_pages() hooks
are put together and a warning comment is added.

This patch changes the order in which memory initialization and page
poisoning hooks are called.  This doesn't lead to any side-effects, as
whenever page poisoning is enabled, memory initialization gets disabled.

Combining setting allocation tags with memory initialization improves
HW_TAGS KASAN performance when init_on_alloc/free is enabled.

[andreyknvl@google.com: fix for "integrate page_alloc init with HW_TAGS"]
  Link: https://lkml.kernel.org/r/65b6028dea2e9a6e8e2cb779b5115c09457363fc.1617122211.git.andreyknvl@google.com

Link: https://lkml.kernel.org/r/e77f0d5b1b20658ef0b8288625c74c2b3690e725.1615296150.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Sergei Trofimovich <slyfox@gentoo.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:41 -07:00
Andrey Konovalov a064cb00d3 kasan: initialize shadow to TAG_INVALID for SW_TAGS
Currently, KASAN_SW_TAGS uses 0xFF as the default tag value for
unallocated memory.  The underlying idea is that since that memory hasn't
been allocated yet, it's only supposed to be dereferenced through a
pointer with the native 0xFF tag.

While this is a good idea in terms on consistency, practically it doesn't
bring any benefit.  Since the 0xFF pointer tag is a match-all tag, it
doesn't matter what tag the accessed memory has.  No accesses through
0xFF-tagged pointers are considered buggy by KASAN.

This patch changes the default tag value for unallocated memory to 0xFE,
which is the tag KASAN uses for inaccessible memory.  This doesn't affect
accesses through 0xFF-tagged pointer to this memory, but this allows KASAN
to detect wild and large out-of-bounds invalid memory accesses through
otherwise-tagged pointers.

This is a prepatory patch for the next one, which changes the tag-based
KASAN modes to not poison the boot memory.

Link: https://lkml.kernel.org/r/c8e93571c18b3528aac5eb33ade213bf133d10ad.1613692950.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:41 -07:00
Linus Torvalds 31a24ae89c Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:

 - MTE asynchronous support for KASan. Previously only synchronous
   (slower) mode was supported. Asynchronous is faster but does not
   allow precise identification of the illegal access.

 - Run kernel mode SIMD with softirqs disabled. This allows using NEON
   in softirq context for crypto performance improvements. The
   conditional yield support is modified to take softirqs into account
   and reduce the latency.

 - Preparatory patches for Apple M1: handle CPUs that only have the VHE
   mode available (host kernel running at EL2), add FIQ support.

 - arm64 perf updates: support for HiSilicon PA and SLLC PMU drivers,
   new functions for the HiSilicon HHA and L3C PMU, cleanups.

 - Re-introduce support for execute-only user permissions but only when
   the EPAN (Enhanced Privileged Access Never) architecture feature is
   available.

 - Disable fine-grained traps at boot and improve the documented boot
   requirements.

 - Support CONFIG_KASAN_VMALLOC on arm64 (only with KASAN_GENERIC).

 - Add hierarchical eXecute Never permissions for all page tables.

 - Add arm64 prctl(PR_PAC_{SET,GET}_ENABLED_KEYS) allowing user programs
   to control which PAC keys are enabled in a particular task.

 - arm64 kselftests for BTI and some improvements to the MTE tests.

 - Minor improvements to the compat vdso and sigpage.

 - Miscellaneous cleanups.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (86 commits)
  arm64/sve: Add compile time checks for SVE hooks in generic functions
  arm64/kernel/probes: Use BUG_ON instead of if condition followed by BUG.
  arm64: pac: Optimize kernel entry/exit key installation code paths
  arm64: Introduce prctl(PR_PAC_{SET,GET}_ENABLED_KEYS)
  arm64: mte: make the per-task SCTLR_EL1 field usable elsewhere
  arm64/sve: Remove redundant system_supports_sve() tests
  arm64: fpsimd: run kernel mode NEON with softirqs disabled
  arm64: assembler: introduce wxN aliases for wN registers
  arm64: assembler: remove conditional NEON yield macros
  kasan, arm64: tests supports for HW_TAGS async mode
  arm64: mte: Report async tag faults before suspend
  arm64: mte: Enable async tag check fault
  arm64: mte: Conditionally compile mte_enable_kernel_*()
  arm64: mte: Enable TCO in functions that can read beyond buffer limits
  kasan: Add report for async mode
  arm64: mte: Drop arch_enable_tagging()
  kasan: Add KASAN mode kernel parameter
  arm64: mte: Add asynchronous mode support
  arm64: Get rid of CONFIG_ARM64_VHE
  arm64: Cope with CPUs stuck in VHE mode
  ...
2021-04-26 10:25:03 -07:00
Walter Wu 02c587733c kasan: remove redundant config option
CONFIG_KASAN_STACK and CONFIG_KASAN_STACK_ENABLE both enable KASAN stack
instrumentation, but we should only need one config, so that we remove
CONFIG_KASAN_STACK_ENABLE and make CONFIG_KASAN_STACK workable.  see [1].

When enable KASAN stack instrumentation, then for gcc we could do no
prompt and default value y, and for clang prompt and default value n.

This patch fixes the following compilation warning:

  include/linux/kasan.h:333:30: warning: 'CONFIG_KASAN_STACK' is not defined, evaluates to 0 [-Wundef]

[akpm@linux-foundation.org: fix merge snafu]

Link: https://bugzilla.kernel.org/show_bug.cgi?id=210221 [1]
Link: https://lkml.kernel.org/r/20210226012531.29231-1-walter-zh.wu@mediatek.com
Fixes: d9b571c885 ("kasan: fix KASAN_STACK dependency for HW_TAGS")
Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16 16:10:36 -07:00
Vincenzo Frascino 8f7b505475 kasan: Add report for async mode
KASAN provides an asynchronous mode of execution.

Add reporting functionality for this mode.

Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Link: https://lore.kernel.org/r/20210315132019.33202-5-vincenzo.frascino@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-04-11 10:56:39 +01:00
Andrey Konovalov 200072ce33 kasan: unify large kfree checks
Unify checks in kasan_kfree_large() and in kasan_slab_free_mempool() for
large allocations as it's done for small kfree() allocations.

With this change, kasan_slab_free_mempool() starts checking that the first
byte of the memory that's being freed is accessible.

Link: https://lkml.kernel.org/r/14ffc4cd867e0b1ed58f7527e3b748a1b4ad08aa.1612546384.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:03 -08:00
Andrey Konovalov 928501344f kasan, mm: don't save alloc stacks twice
Patch series "kasan: optimizations and fixes for HW_TAGS", v4.

This patchset makes the HW_TAGS mode more efficient, mostly by reworking
poisoning approaches and simplifying/inlining some internal helpers.

With this change, the overhead of HW_TAGS annotations excluding setting
and checking memory tags is ~3%.  The performance impact caused by tags
will be unknown until we have hardware that supports MTE.

As a side-effect, this patchset speeds up generic KASAN by ~15%.

This patch (of 13):

Currently KASAN saves allocation stacks in both kasan_slab_alloc() and
kasan_kmalloc() annotations.  This patch changes KASAN to save allocation
stacks for slab objects from kmalloc caches in kasan_kmalloc() only, and
stacks for other slab objects in kasan_slab_alloc() only.

This change requires ____kasan_kmalloc() knowing whether the object
belongs to a kmalloc cache.  This is implemented by adding a flag field to
the kasan_info structure.  That flag is only set for kmalloc caches via a
new kasan_cache_create_kmalloc() annotation.

Link: https://lkml.kernel.org/r/cover.1612546384.git.andreyknvl@google.com
Link: https://lkml.kernel.org/r/7c673ebca8d00f40a7ad6f04ab9a2bddeeae2097.1612546384.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-26 09:41:02 -08:00
Andrey Konovalov 611806b4bf kasan: fix bug detection via ksize for HW_TAGS mode
The currently existing kasan_check_read/write() annotations are intended
to be used for kernel modules that have KASAN compiler instrumentation
disabled. Thus, they are only relevant for the software KASAN modes that
rely on compiler instrumentation.

However there's another use case for these annotations: ksize() checks
that the object passed to it is indeed accessible before unpoisoning the
whole object. This is currently done via __kasan_check_read(), which is
compiled away for the hardware tag-based mode that doesn't rely on
compiler instrumentation. This leads to KASAN missing detecting some
memory corruptions.

Provide another annotation called kasan_check_byte() that is available
for all KASAN modes. As the implementation rename and reuse
kasan_check_invalid_free(). Use this new annotation in ksize().
To avoid having ksize() as the top frame in the reported stack trace
pass _RET_IP_ to __kasan_check_byte().

Also add a new ksize_uaf() test that checks that a use-after-free is
detected via ksize() itself, and via plain accesses that happen later.

Link: https://linux-review.googlesource.com/id/Iaabf771881d0f9ce1b969f2a62938e99d3308ec5
Link: https://lkml.kernel.org/r/f32ad74a60b28d8402482a38476f02bb7600f620.1610733117.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24 13:38:31 -08:00
Andrey Konovalov 027b37b552 kasan: move _RET_IP_ to inline wrappers
Generic mm functions that call KASAN annotations that might report a bug
pass _RET_IP_ to them as an argument. This allows KASAN to include the
name of the function that called the mm function in its report's header.

Now that KASAN has inline wrappers for all of its annotations, move
_RET_IP_ to those wrappers to simplify annotation call sites.

Link: https://linux-review.googlesource.com/id/I8fb3c06d49671305ee184175a39591bc26647a67
Link: https://lkml.kernel.org/r/5c1490eddf20b436b8c4eeea83fce47687d5e4a4.1610733117.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-24 13:38:31 -08:00
Vincenzo Frascino 49c6631d3b kasan: add explicit preconditions to kasan_report()
Patch series "kasan: Fix metadata detection for KASAN_HW_TAGS", v5.

With the introduction of KASAN_HW_TAGS, kasan_report() currently assumes
that every location in memory has valid metadata associated.  This is
due to the fact that addr_has_metadata() returns always true.

As a consequence of this, an invalid address (e.g.  NULL pointer
address) passed to kasan_report() when KASAN_HW_TAGS is enabled, leads
to a kernel panic.

Example below, based on arm64:

   BUG: KASAN: invalid-access in 0x0
   Read at addr 0000000000000000 by task swapper/0/1
   Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
   Mem abort info:
     ESR = 0x96000004
     EC = 0x25: DABT (current EL), IL = 32 bits
     SET = 0, FnV = 0
     EA = 0, S1PTW = 0
   Data abort info:
     ISV = 0, ISS = 0x00000004
     CM = 0, WnR = 0

  ...

   Call trace:
    mte_get_mem_tag+0x24/0x40
    kasan_report+0x1a4/0x410
    alsa_sound_last_init+0x8c/0xa4
    do_one_initcall+0x50/0x1b0
    kernel_init_freeable+0x1d4/0x23c
    kernel_init+0x14/0x118
    ret_from_fork+0x10/0x34
   Code: d65f03c0 9000f021 f9428021 b6cfff61 (d9600000)
   ---[ end trace 377c8bb45bdd3a1a ]---
   hrtimer: interrupt took 48694256 ns
   note: swapper/0[1] exited with preempt_count 1
   Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
   SMP: stopping secondary CPUs
   Kernel Offset: 0x35abaf140000 from 0xffff800010000000
   PHYS_OFFSET: 0x40000000
   CPU features: 0x0a7e0152,61c0a030
   Memory Limit: none
   ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---

This series fixes the behavior of addr_has_metadata() that now returns
true only when the address is valid.

This patch (of 2):

With the introduction of KASAN_HW_TAGS, kasan_report() accesses the
metadata only when addr_has_metadata() succeeds.

Add a comment to make sure that the preconditions to the function are
explicitly clarified.

Link: https://lkml.kernel.org/r/20210126134409.47894-1-vincenzo.frascino@arm.com
Link: https://lkml.kernel.org/r/20210126134409.47894-2-vincenzo.frascino@arm.com
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-05 11:03:47 -08:00
Hailong Liu 29970dc24f arm/kasan: fix the array size of kasan_early_shadow_pte[]
The size of kasan_early_shadow_pte[] now is PTRS_PER_PTE which defined
to 512 for arm.  This means that it only covers the prev Linux pte
entries, but not the HWTABLE pte entries for arm.

The reason it currently works is that the symbol kasan_early_shadow_page
immediately following kasan_early_shadow_pte in memory is page aligned,
which makes kasan_early_shadow_pte look like a 4KB size array.  But we
can't ensure the order is always right with different compiler/linker,
or if more bss symbols are introduced.

We had a test with QEMU + vexpress:put a 512KB-size symbol with
attribute __section(".bss..page_aligned") after kasan_early_shadow_pte,
and poisoned it after kasan_early_init().  Then enabled CONFIG_KASAN, it
failed to boot up.

Link: https://lkml.kernel.org/r/20210109044622.8312-1-hailongliiu@yeah.net
Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn>
Signed-off-by: Ziliang Guo <guo.ziliang@zte.com.cn>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-01-12 18:12:54 -08:00
Andrey Konovalov e86f8b09f2 kasan, mm: allow cache merging with no metadata
The reason cache merging is disabled with KASAN is because KASAN puts its
metadata right after the allocated object. When the merged caches have
slightly different sizes, the metadata ends up in different places, which
KASAN doesn't support.

It might be possible to adjust the metadata allocation algorithm and make
it friendly to the cache merging code. Instead this change takes a simpler
approach and allows merging caches when no metadata is present. Which is
the case for hardware tag-based KASAN with kasan.mode=prod.

Link: https://lkml.kernel.org/r/37497e940bfd4b32c0a93a702a9ae4cf061d5392.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/Ia114847dfb2244f297d2cb82d592bf6a07455dba
Co-developed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Signed-off-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:09 -08:00
Andrey Konovalov eeb3160c24 kasan, mm: rename kasan_poison_kfree
Rename kasan_poison_kfree() to kasan_slab_free_mempool() as it better
reflects what this annotation does. Also add a comment that explains the
PageSlab() check.

No functional changes.

Link: https://lkml.kernel.org/r/141675fb493555e984c5dca555e9d9f768c7bbaa.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/I5026f87364e556b506ef1baee725144bb04b8810
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:09 -08:00
Andrey Konovalov 34303244f2 kasan, mm: check kasan_enabled in annotations
Declare the kasan_enabled static key in include/linux/kasan.h and in
include/linux/mm.h and check it in all kasan annotations. This allows to
avoid any slowdown caused by function calls when kasan_enabled is
disabled.

Link: https://lkml.kernel.org/r/9f90e3c0aa840dbb4833367c2335193299f69023.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/I2589451d3c96c97abbcbf714baabe6161c6f153e
Co-developed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Signed-off-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:09 -08:00
Andrey Konovalov bffe690708 kasan: open-code kasan_unpoison_slab
There's the external annotation kasan_unpoison_slab() that is currently
defined as static inline and uses kasan_unpoison_range(). Open-code this
function in mempool.c. Otherwise with an upcoming change this function
will result in an unnecessary function call.

Link: https://lkml.kernel.org/r/131a6694a978a9a8b150187e539eecc8bcbf759b.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/Ia7c8b659f79209935cbaab3913bf7f082cc43a0e
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:09 -08:00
Andrey Konovalov c0054c565a kasan: inline kasan_reset_tag for tag-based modes
Using kasan_reset_tag() currently results in a function call. As it's
called quite often from the allocator code, this leads to a noticeable
slowdown. Move it to include/linux/kasan.h and turn it into a static
inline function. Also remove the now unneeded reset_tag() internal KASAN
macro and use kasan_reset_tag() instead.

Link: https://lkml.kernel.org/r/6940383a3a9dfb416134d338d8fac97a9ebb8686.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/I4d2061acfe91d480a75df00b07c22d8494ef14b5
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:08 -08:00
Andrey Konovalov d56a9ef84b kasan, arm64: unpoison stack only with CONFIG_KASAN_STACK
There's a config option CONFIG_KASAN_STACK that has to be enabled for
KASAN to use stack instrumentation and perform validity checks for
stack variables.

There's no need to unpoison stack when CONFIG_KASAN_STACK is not enabled.
Only call kasan_unpoison_task_stack[_below]() when CONFIG_KASAN_STACK is
enabled.

Note, that CONFIG_KASAN_STACK is an option that is currently always
defined when CONFIG_KASAN is enabled, and therefore has to be tested
with #if instead of #ifdef.

Link: https://lkml.kernel.org/r/d09dd3f8abb388da397fd11598c5edeaa83fe559.1606162397.git.andreyknvl@google.com
Link: https://linux-review.googlesource.com/id/If8a891e9fe01ea543e00b576852685afec0887e3
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:08 -08:00
Andrey Konovalov 2e903b9147 kasan, arm64: implement HW_TAGS runtime
Provide implementation of KASAN functions required for the hardware
tag-based mode.  Those include core functions for memory and pointer
tagging (tags_hw.c) and bug reporting (report_tags_hw.c).  Also adapt
common KASAN code to support the new mode.

Link: https://lkml.kernel.org/r/cfd0fbede579a6b66755c98c88c108e54f9c56bf.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:08 -08:00