kernel_optimize_test/lib
Trent Piepho 456554040e lib/math/rational.c: fix divide by zero
[ Upstream commit 65a0d3c14685663ba111038a35db70f559e39336 ]

If the input is out of the range of the allowed values, either larger than
the largest value or closer to zero than the smallest non-zero allowed
value, then a division by zero would occur.

In the case of input too large, the division by zero will occur on the
first iteration.  The best result (largest allowed value) will be found by
always choosing the semi-convergent and excluding the denominator based
limit when finding it.

In the case of the input too small, the division by zero will occur on the
second iteration.  The numerator based semi-convergent should not be
calculated to avoid the division by zero.  But the semi-convergent vs
previous convergent test is still needed, which effectively chooses
between 0 (the previous convergent) vs the smallest allowed fraction (best
semi-convergent) as the result.

Link: https://lkml.kernel.org/r/20210525144250.214670-1-tpiepho@gmail.com
Fixes: 323dd2c3ed ("lib/math/rational.c: fix possible incorrect result from rational fractions helper")
Signed-off-by: Trent Piepho <tpiepho@gmail.com>
Reported-by: Yiyuan Guo <yguoaz@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Oskar Schirmer <oskar@scara.com>
Cc: Daniel Latypov <dlatypov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-14 16:56:51 +02:00
..
842
crypto crypto: poly1305 - fix poly1305_core_setkey() declaration 2021-05-14 09:50:13 +02:00
dim
fonts Fonts: Replace discarded const qualifier 2020-11-03 10:51:34 +01:00
kunit linux-kselftest-kunit-5.10-rc1 2020-10-18 14:45:59 -07:00
livepatch
lz4 lib/lz4: explicitly support in-place decompression 2021-06-10 13:39:29 +02:00
lzo
math lib/math/rational.c: fix divide by zero 2021-07-14 16:56:51 +02:00
mpi lib/mpi/mpi-bit.c: fix spello of "functions" 2020-10-16 11:11:20 -07:00
pldmfw
raid6 lib/raid6: Let $(UNROLL) rules work with macOS userland 2021-01-19 18:27:25 +01:00
reed_solomon
vdso
xz
zlib_deflate
zlib_dfltcc zlib: move EXPORT_SYMBOL() and MODULE_LICENSE() out of dfltcc_syms.c 2021-01-06 14:56:51 +01:00
zlib_inflate
zstd
.gitignore
argv_split.c
ashldi3.c
ashrdi3.c
asn1_decoder.c
assoc_array.c
atomic64_test.c
atomic64.c
audit.c
bcd.c
bch.c
bitfield_kunit.c lib: kunit: Fix compilation test when using TEST_BIT_FIELD_COMPILE 2020-10-16 13:25:14 -06:00
bitmap.c lib: bitmap: delete duplicated words 2020-10-16 11:11:19 -07:00
bitrev.c
bootconfig.c
bsearch.c
btree.c
bucket_locks.c
bug.c bug: Remove redundant condition check in report_bug 2021-05-14 09:50:32 +02:00
build_OID_registry
bust_spinlocks.c
check_signature.c
checksum.c
clz_ctz.c
clz_tab.c
cmdline.c
cmpdi2.c
compat_audit.c
cpu_rmap.c
cpumask.c Revert "lib: Restrict cpumask_local_spread to houskeeping CPUs" 2021-02-17 11:02:24 +01:00
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
crc4.c
crc7.c
crc8.c
crc16.c
crc32.c lib/crc32.c: fix trivial typo in preprocessor condition 2020-10-16 11:11:20 -07:00
crc32defs.h
crc32test.c lib/crc32test: remove extra local_irq_disable/enable 2020-11-02 12:14:19 -08:00
crc64.c
ctype.c
debug_info.c
debug_locks.c locking/lockdep: Improve noinstr vs errors 2021-06-30 08:47:18 -04:00
debugobjects.c debugobjects: Free per CPU pool after CPU unplug 2020-10-01 16:13:54 +02:00
dec_and_lock.c
decompress_bunzip2.c lib: decompress_bunzip2: delete duplicated words 2020-10-16 11:11:19 -07:00
decompress_inflate.c
decompress_unlz4.c
decompress_unlzma.c
decompress_unlzo.c
decompress_unxz.c
decompress_unzstd.c
decompress.c
devres.c
digsig.c
dump_stack.c
dynamic_debug.c dyndbg: fix parsing file query without a line-range suffix 2021-05-11 14:47:11 +02:00
dynamic_queue_limits.c lib: dynamic_queue_limits: delete duplicated words + fix typo 2020-10-16 11:11:20 -07:00
earlycpio.c lib: earlycpio: delete duplicated words 2020-10-16 11:11:20 -07:00
errname.c
error-inject.c
errseq.c
extable.c
fault-inject-usercopy.c lib, include/linux: add usercopy failure capability 2020-10-16 11:11:22 -07:00
fault-inject.c
fdt_addresses.c
fdt_empty_tree.c
fdt_ro.c
fdt_rw.c
fdt_strerror.c
fdt_sw.c
fdt_wip.c
fdt.c
find_bit_benchmark.c
find_bit.c kernel.h: split out min()/max() et al. helpers 2020-10-16 11:11:19 -07:00
flex_proportions.c
gen_crc32table.c
gen_crc64table.c
genalloc.c lib/genalloc: fix the overflow when size is too big 2021-01-12 20:18:16 +01:00
generic-radix-tree.c
glob.c
globtest.c
hexdump.c kernel.h: split out min()/max() et al. helpers 2020-10-16 11:11:19 -07:00
hweight.c
idr.c XArray updates for 5.9 2020-10-20 14:39:37 -07:00
inflate.c
interval_tree_test.c
interval_tree.c
iomap_copy.c
iomap.c
iommu-helper.c
iov_iter.c iov_iter_fault_in_readable() should do nothing in xarray case 2021-07-14 16:55:39 +02:00
irq_poll.c
irq_regs.c
is_single_threaded.c
kasprintf.c
Kconfig x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}() 2020-10-06 11:18:04 +02:00
Kconfig.debug locking/lockdep: Reduce LOCKDEP dependency list 2021-07-14 16:56:05 +02:00
Kconfig.kasan KASAN: port KASAN Tests to KUnit 2020-10-13 18:38:32 -07:00
Kconfig.kcsan
Kconfig.kgdb
Kconfig.ubsan ubsan: introduce CONFIG_UBSAN_LOCAL_BOUNDS for Clang 2020-10-16 11:11:22 -07:00
kfifo.c
klist.c
kobject_uevent.c kobject_uevent: remove warning in init_uevent_argv() 2021-05-19 10:13:18 +02:00
kobject.c
kstrtox.c lib: vsprintf: Fix handling of number field widths in vsscanf 2021-07-14 16:55:57 +02:00
kstrtox.h lib: vsprintf: Fix handling of number field widths in vsscanf 2021-07-14 16:55:57 +02:00
libcrc32c.c lib: libcrc32c: delete duplicated words 2020-10-16 11:11:19 -07:00
linear_ranges.c
list_debug.c
list_sort.c
list-test.c
llist.c
locking-selftest-hardirq.h
locking-selftest-mutex.h
locking-selftest-rlock-hardirq.h
locking-selftest-rlock-softirq.h
locking-selftest-rlock.h
locking-selftest-rsem.h
locking-selftest-rtmutex.h
locking-selftest-softirq.h
locking-selftest-spin-hardirq.h
locking-selftest-spin-softirq.h
locking-selftest-spin.h
locking-selftest-wlock-hardirq.h
locking-selftest-wlock-softirq.h
locking-selftest-wlock.h
locking-selftest-wsem.h
locking-selftest.c lockdep/selftests: Fix selftests vs PROVE_RAW_LOCK_NESTING 2021-07-14 16:56:10 +02:00
lockref.c
logic_pio.c PCI: Fix pci_register_io_range() memory leak 2021-03-17 17:06:25 +01:00
lru_cache.c
lshrdi3.c
Makefile selftest/fpu: avoid clang warning 2020-12-11 14:02:14 -08:00
memcat_p.c
memory-notifier-error-inject.c
memregion.c
memweight.c
muldi3.c
net_utils.c
netdev-notifier-error-inject.c
nlattr.c net: fix nla_strcmp to handle more then one trailing null character 2021-05-19 10:13:08 +02:00
nmi_backtrace.c
nodemask.c
notifier-error-inject.c
notifier-error-inject.h
objagg.c
of-reconfig-notifier-error-inject.c
oid_registry.c
once.c
packing.c
parman.c
parser.c
pci_iomap.c
percpu_counter.c lib/percpu_counter.c: use helper macro abs() 2020-10-16 11:11:20 -07:00
percpu_test.c
percpu-refcount.c percpu_ref: don't refer to ref->data if it isn't allocated 2020-10-09 12:32:06 -06:00
plist.c
pm-notifier-error-inject.c
radix-tree.c XArray updates for 5.9 2020-10-20 14:39:37 -07:00
random32.c random32: add a selftest for the prandom32 code 2020-10-24 20:21:57 +02:00
ratelimit.c
rbtree_test.c
rbtree.c
refcount.c
rhashtable.c
sbitmap.c
scatterlist.c lib/scatterlist: use consistent sg_copy_buffer() return type 2020-10-29 08:55:45 -06:00
seq_buf.c seq_buf: Make trace_seq_putmem_hex() support data longer than 8 2021-07-14 16:55:46 +02:00
sg_pool.c
sg_split.c
sha1.c
show_mem.c
siphash.c
smp_processor_id.c
sort.c
stackdepot.c lib: stackdepot: turn depot_lock spinlock to raw_spinlock 2021-05-22 11:40:55 +02:00
stmp_device.c
string_helpers.c
string.c
strncpy_from_user.c lib/strncpy_from_user.c: Mask out bytes after NUL terminator. 2020-11-19 11:56:16 -08:00
strnlen_user.c
syscall.c lib/syscall: fix syscall registers retrieval on 32-bit platforms 2020-12-03 09:52:44 -08:00
test_bitmap.c
test_bitops.c
test_bits.c
test_blackhole_dev.c
test_bpf.c
test_debug_virtual.c
test_firmware.c test_firmware: Test partial read support 2020-10-05 13:37:04 +02:00
test_fpu.c
test_free_pages.c mm/page_alloc.c: fix freeing non-compound pages 2020-10-13 18:38:33 -07:00
test_hash.c
test_hexdump.c
test_hmm_uapi.h
test_hmm.c lib/test_hmm.c: fix an error code in dmirror_allocate_chunk() 2020-10-16 11:11:20 -07:00
test_ida.c
test_kasan_module.c KASAN: port KASAN Tests to KUnit 2020-10-13 18:38:32 -07:00
test_kasan.c kasan: fix unit tests with CONFIG_UBSAN_LOCAL_BOUNDS enabled 2021-05-19 10:13:11 +02:00
test_kmod.c
test_linear_ranges.c
test_list_sort.c
test_lockup.c
test_memcat_p.c
test_meminit.c
test_min_heap.c
test_module.c
test_objagg.c
test_overflow.c
test_parman.c
test_printf.c
test_rhashtable.c
test_siphash.c
test_sort.c
test_stackinit.c
test_static_key_base.c
test_static_keys.c
test_string.c
test_strscpy.c
test_sysctl.c lib: test_sysctl: delete duplicated words 2020-10-16 11:11:20 -07:00
test_ubsan.c
test_user_copy.c
test_uuid.c
test_vmalloc.c
test_xarray.c XArray: Fix splitting to non-zero orders 2021-04-16 11:43:21 +02:00
test-kstrtox.c
test-string_helpers.c
textsearch.c
timerqueue.c
ts_bm.c
ts_fsm.c
ts_kmp.c
ubsan.c ubsan: implement __ubsan_handle_alignment_assumption 2021-02-17 11:02:24 +01:00
ubsan.h ubsan: implement __ubsan_handle_alignment_assumption 2021-02-17 11:02:24 +01:00
ucmpdi2.c
ucs2_string.c
usercopy.c lib, uaccess: add failure injection to usercopy functions 2020-10-16 11:11:22 -07:00
uuid.c
vsprintf.c lib: vsprintf: Fix handling of number field widths in vsscanf 2021-07-14 16:55:57 +02:00
win_minmax.c
xarray.c XArray: Fix splitting to non-zero orders 2021-04-16 11:43:21 +02:00
xxhash.c