kernel/linux.git/lib/test_kasan.c, branch v5.15.85

kasan: test: Silence GCC 12 warnings

2022-08-17T12:23:05+00:00

[ Upstream commit aaf50b1969d7933a51ea421b11432a7fb90974e3 ] GCC 12 continues to get smarter about array accesses. The KASAN tests are expecting to explicitly test out-of-bounds conditions at run-time, so hide the variable from GCC, to avoid warnings like: ../lib/test_kasan.c: In function 'ksize_uaf': ../lib/test_kasan.c:790:61: warning: array subscript 120 is outside array bounds of 'void[120]' [-Warray-bounds] 790 | KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]); | ~~~~~~~~~~~~~~~~~~~~~~^~~~~~ ../lib/test_kasan.c:97:9: note: in definition of macro 'KUNIT_EXPECT_KASAN_FAIL' 97 | expression; \ | ^~~~~~~~~~ Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Vincenzo Frascino Cc: kasan-dev@googlegroups.com Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220608214024.1068451-1-keescook@chromium.org Signed-off-by: Sasha Levin

Merge branch 'akpm' (patches from Andrew)

2021-09-03T17:08:28+00:00

Merge misc updates from Andrew Morton: "173 patches. Subsystems affected by this series: ia64, ocfs2, block, and mm (debug, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock, oom-kill, migration, ksm, percpu, vmstat, and madvise)" * emailed patches from Andrew Morton : (173 commits) mm/madvise: add MADV_WILLNEED to process_madvise() mm/vmstat: remove unneeded return value mm/vmstat: simplify the array size calculation mm/vmstat: correct some wrong comments mm/percpu,c: remove obsolete comments of pcpu_chunk_populated() selftests: vm: add COW time test for KSM pages selftests: vm: add KSM merging time test mm: KSM: fix data type selftests: vm: add KSM merging across nodes test selftests: vm: add KSM zero page merging test selftests: vm: add KSM unmerge test selftests: vm: add KSM merge test mm/migrate: correct kernel-doc notation mm: wire up syscall process_mrelease mm: introduce process_mrelease system call memblock: make memblock_find_in_range method private mm/mempolicy.c: use in_task() in mempolicy_slab_node() mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies mm/mempolicy: advertise new MPOL_PREFERRED_MANY mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY ...

kasan: test: clean up ksize_uaf

2021-09-03T16:58:15+00:00

Some KASAN tests use global variables to store function returns values so that the compiler doesn't optimize away these functions. ksize_uaf() doesn't call any functions, so it doesn't need to use kasan_int_result. Use volatile accesses instead, to be consistent with other similar tests. Link: https://lkml.kernel.org/r/a1fc34faca4650f4a6e4dfb3f8d8d82c82eb953a.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan: test: only do kmalloc_uaf_memset for generic mode

2021-09-03T16:58:14+00:00

kmalloc_uaf_memset() writes to freed memory, which is only safe with the GENERIC mode (as it uses quarantine). For other modes, this test corrupts kernel memory, which might result in a crash. Only enable kmalloc_uaf_memset() for the GENERIC mode. Link: https://lkml.kernel.org/r/2e1c87b607b1292556cde3cab2764f108542b60c.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan: test: disable kmalloc_memmove_invalid_size for HW_TAGS

2021-09-03T16:58:14+00:00

The HW_TAGS mode doesn't check memmove for negative size. As a result, the kmalloc_memmove_invalid_size test corrupts memory, which can result in a crash. Disable this test with HW_TAGS KASAN. Link: https://lkml.kernel.org/r/088733a06ac21eba29aa85b6f769d2abd74f9638.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan: test: avoid corrupting memory via memset

2021-09-03T16:58:14+00:00

kmalloc_oob_memset_*() tests do writes past the allocated objects. As the result, they corrupt memory, which might lead to crashes with the HW_TAGS mode, as it neither uses quarantine nor redzones. Adjust the tests to only write memory within the aligned kmalloc objects. Also add a comment mentioning that memset tests are designed to touch both valid and invalid memory. Link: https://lkml.kernel.org/r/64fd457668a16e7b58d094f14a165f9d5170c5a9.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan: test: avoid writing invalid memory

2021-09-03T16:58:14+00:00

Multiple KASAN tests do writes past the allocated objects or writes to freed memory. Turn these writes into reads to avoid corrupting memory. Otherwise, these tests might lead to crashes with the HW_TAGS mode, as it neither uses quarantine nor redzones. Link: https://lkml.kernel.org/r/c3cd2a383e757e27dd9131635fc7d09a48a49cf9.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kasan: test: rework kmalloc_oob_right

2021-09-03T16:58:14+00:00

Patch series "kasan: test: avoid crashing the kernel with HW_TAGS", v2. KASAN tests do out-of-bounds and use-after-free accesses. Running the tests works fine for the GENERIC mode, as it uses qurantine and redzones. But the HW_TAGS mode uses neither, and running the tests might crash the kernel. Rework the tests to avoid corrupting kernel memory. This patch (of 8): Rework kmalloc_oob_right() to do these bad access checks: 1. An unaligned access one byte past the requested kmalloc size (can only be detected by KASAN_GENERIC). 2. An aligned access into the first out-of-bounds granule that falls within the aligned kmalloc object. 3. Out-of-bounds access past the aligned kmalloc object. Test #3 deliberately uses a read access to avoid corrupting memory. Otherwise, this test might lead to crashes with the HW_TAGS mode, as it neither uses quarantine nor redzones. Link: https://lkml.kernel.org/r/cover.1628779805.git.andreyknvl@gmail.com Link: https://lkml.kernel.org/r/474aa8b7b538c6737a4c6d0090350af2e1776bef.1628779805.git.andreyknvl@gmail.com Signed-off-by: Andrey Konovalov Reviewed-by: Marco Elver Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Alexander Potapenko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

arm64: kasan: mte: remove redundant mte_report_once logic

2021-08-02T17:15:28+00:00

We have special logic to suppress MTE tag check fault reporting, based on a global `mte_report_once` and `reported` variables. These can be used to suppress calling kasan_report() when taking a tag check fault, but do not prevent taking the fault in the first place, nor does they affect the way we disable tag checks upon taking a fault. The core KASAN code already defaults to reporting a single fault, and has a `multi_shot` control to permit reporting multiple faults. The only place we transiently alter `mte_report_once` is in lib/test_kasan.c, where we also the `multi_shot` state as the same time. Thus `mte_report_once` and `reported` are redundant, and can be removed. When a tag check fault is taken, tag checking will be disabled by `do_tag_recovery` and must be explicitly re-enabled if desired. The test code does this by calling kasan_enable_tagging_sync(). This patch removes the redundant mte_report_once() logic and associated variables. Signed-off-by: Mark Rutland Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Will Deacon Cc: Vincenzo Frascino Reviewed-by: Catalin Marinas Reviewed-by: Andrey Konovalov Tested-by: Andrey Konovalov Link: https://lore.kernel.org/r/20210714143843.56537-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas

lib/test: fix spelling mistakes

2021-07-08T18:48:20+00:00

Fix some spelling mistakes in comments found by "codespell": thats ==> that's unitialized ==> uninitialized panicing ==> panicking sucess ==> success possitive ==> positive intepreted ==> interpreted Link: https://lkml.kernel.org/r/20210607133036.12525-2-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei Acked-by: Yonghong Song [test_bfp.c] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds