[PATCH v2 00/33] kmsan: Enable on s390

From: Ilya Leoshkevich
Date: Tue Nov 21 2023 - 17:03:45 EST


v1: https://lore.kernel.org/lkml/20231115203401.2495875-1-iii@xxxxxxxxxxxxx/
v1 -> v2: Add comments, sort #includes, introduce
memset_no_sanitize_memory() and use it to avoid unpoisoning
of redzones, change vmalloc alignment to _REGION3_SIZE, add
R-bs (Alexander P.).

Fix building
[PATCH 28/33] s390/string: Add KMSAN support
with FORTIFY_SOURCE.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202311170550.bSBo44ix-lkp@xxxxxxxxx/

Hi,

This series provides the minimal support for Kernel Memory Sanitizer on
s390. Kernel Memory Sanitizer is clang-only instrumentation for finding
accesses to uninitialized memory. The clang support for s390 has already
been merged [1].

With this series, I can successfully boot s390 defconfig and
debug_defconfig with kmsan.panic=1. The tool found one real
s390-specific bug (fixed in master).

Best regards,
Ilya

[1] https://reviews.llvm.org/D148596

Ilya Leoshkevich (33):
ftrace: Unpoison ftrace_regs in ftrace_ops_list_func()
kmsan: Make the tests compatible with kmsan.panic=1
kmsan: Disable KMSAN when DEFERRED_STRUCT_PAGE_INIT is enabled
kmsan: Increase the maximum store size to 4096
kmsan: Fix is_bad_asm_addr() on arches with overlapping address spaces
kmsan: Fix kmsan_copy_to_user() on arches with overlapping address
spaces
kmsan: Remove a useless assignment from
kmsan_vmap_pages_range_noflush()
kmsan: Remove an x86-specific #include from kmsan.h
kmsan: Introduce kmsan_memmove_metadata()
kmsan: Expose kmsan_get_metadata()
kmsan: Export panic_on_kmsan
kmsan: Allow disabling KMSAN checks for the current task
kmsan: Introduce memset_no_sanitize_memory()
kmsan: Support SLAB_POISON
kmsan: Use ALIGN_DOWN() in kmsan_get_metadata()
mm: slub: Let KMSAN access metadata
mm: kfence: Disable KMSAN when checking the canary
lib/string: Add KMSAN support to strlcpy() and strlcat()
lib/zlib: Unpoison DFLTCC output buffers
kmsan: Accept ranges starting with 0 on s390
s390: Turn off KMSAN for boot, vdso and purgatory
s390: Use a larger stack for KMSAN
s390/boot: Add the KMSAN runtime stub
s390/checksum: Add a KMSAN check
s390/cpacf: Unpoison the results of cpacf_trng()
s390/ftrace: Unpoison ftrace_regs in kprobe_ftrace_handler()
s390/mm: Define KMSAN metadata for vmalloc and modules
s390/string: Add KMSAN support
s390/traps: Unpoison the kernel_stack_overflow()'s pt_regs
s390/uaccess: Add KMSAN support to put_user() and get_user()
s390/unwind: Disable KMSAN checks
s390: Implement the architecture-specific kmsan functions
kmsan: Enable on s390

Documentation/dev-tools/kmsan.rst | 4 +-
arch/s390/Kconfig | 1 +
arch/s390/Makefile | 2 +-
arch/s390/boot/Makefile | 3 +
arch/s390/boot/kmsan.c | 6 ++
arch/s390/boot/startup.c | 8 ++
arch/s390/boot/string.c | 16 ++++
arch/s390/include/asm/checksum.h | 2 +
arch/s390/include/asm/cpacf.h | 2 +
arch/s390/include/asm/kmsan.h | 36 +++++++++
arch/s390/include/asm/pgtable.h | 10 +++
arch/s390/include/asm/string.h | 20 +++--
arch/s390/include/asm/thread_info.h | 2 +-
arch/s390/include/asm/uaccess.h | 110 ++++++++++++++++++++--------
arch/s390/kernel/ftrace.c | 1 +
arch/s390/kernel/traps.c | 6 ++
arch/s390/kernel/unwind_bc.c | 4 +
arch/s390/kernel/vdso32/Makefile | 3 +-
arch/s390/kernel/vdso64/Makefile | 3 +-
arch/s390/purgatory/Makefile | 2 +
include/linux/kmsan-checks.h | 26 +++++++
include/linux/kmsan.h | 23 ++++++
include/linux/kmsan_types.h | 2 +-
kernel/trace/ftrace.c | 1 +
lib/string.c | 6 ++
lib/zlib_dfltcc/dfltcc.h | 1 +
lib/zlib_dfltcc/dfltcc_util.h | 23 ++++++
mm/Kconfig | 1 +
mm/kfence/core.c | 5 +-
mm/kmsan/core.c | 2 +-
mm/kmsan/hooks.c | 30 +++++++-
mm/kmsan/init.c | 5 +-
mm/kmsan/instrumentation.c | 11 +--
mm/kmsan/kmsan.h | 9 +--
mm/kmsan/kmsan_test.c | 5 ++
mm/kmsan/report.c | 7 +-
mm/kmsan/shadow.c | 9 +--
mm/slub.c | 12 ++-
38 files changed, 345 insertions(+), 74 deletions(-)
create mode 100644 arch/s390/boot/kmsan.c
create mode 100644 arch/s390/include/asm/kmsan.h

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2.41.0