Linus Torvalds 91f28da8c9 random32: make prandom_u32() less predictable ... This is the cleanup of the latest series of prandom_u32 experimentations consisting in using SipHash instead of Tausworthe to produce the randoms used by the network stack. The changes to the files were kept minimal, and the controversial commit that used to take noise from the fast_pool (f227e3ec3b) was reverted. Instead, a dedicated "net_rand_noise" per_cpu variable is fed from various sources of activities (networking, scheduling) to perturb the SipHash state using fast, non-trivially predictable data, instead of keeping it fully deterministic. The goal is essentially to make any occasional memory leakage or brute-force attempt useless. The resulting code was verified to be very slightly faster on x86_64 than what is was with the controversial commit above, though this remains barely above measurement noise. It was also tested on i386 and arm, and build- tested only on arm64. The whole discussion around this is archived here: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/ -----BEGIN PGP SIGNATURE----- iQIcBAABAgAGBQJflHDtAAoJEE44bZycYXAvxXUP/A9aKCaSnJUgYi/0Fa507bi9 yJkNs6cotQfzmG8GznQWdG2mdsviqI/d08UdIHD9JHKoin3wcT4+0So546pCw9BR tlrHnFcRnqEqXFLggnqkKnnIgGNNTppMDSi96BplNoXYXAMRjjvKW9Vl94lU2Abk a+aOOJRu4Vzj/5tRT3fkg/ldN6YGZ6nbqVkzd0WAwuYYIj1VSYUSkLgKc65n+4Xp ISnVWObeHJ+tnBRDVudTaUNYi7T3QvCF9glZZlFUVBDQbTRSqjMBSUmnBnOg1mhO Q5nY6xrfTi/0i39+/wOUUOTaxe7YggymibQfN+Y26w1rPO45RkvORiPKvXlfZWaI a3wh1TMoDAptrW9VXiO9pJv6a4xC16c7FyyTnGkP4jP+HTFdgmgixoNmPKrBxuEZ X8O+HOSf155j057aECMivk8bIj4FfLmYt2ciWqRZTVCwu9uK29AJSMx0SphTmYQ0 p0HaJ8mHKnFVViX9n+YOPRfZDIRGH1zTOxzPhEkzuX8vx/4uiXsbp/ILxg0uZ913 DgMk1rzzBlZsL7QqJQnf9JM810pFcU/PI7Y7PKaGKz3ntkJT2WV7gMeg+Wwv9254 pPccvffYzdbtJAHgj+If8lHwixE33u5RscXqjpxIWLPcKTOLQNIf+6bRQ86sA+Kq Vbza8sDu6IWhvApCGLmB =KHhI -----END PGP SIGNATURE----- Merge tag '20201024-v4-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/prandom Pull random32 updates from Willy Tarreau: "Make prandom_u32() less predictable. This is the cleanup of the latest series of prandom_u32 experimentations consisting in using SipHash instead of Tausworthe to produce the randoms used by the network stack. The changes to the files were kept minimal, and the controversial commit that used to take noise from the fast_pool (f227e3ec3b) was reverted. Instead, a dedicated "net_rand_noise" per_cpu variable is fed from various sources of activities (networking, scheduling) to perturb the SipHash state using fast, non-trivially predictable data, instead of keeping it fully deterministic. The goal is essentially to make any occasional memory leakage or brute-force attempt useless. The resulting code was verified to be very slightly faster on x86_64 than what is was with the controversial commit above, though this remains barely above measurement noise. It was also tested on i386 and arm, and build- tested only on arm64" Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/ * tag '20201024-v4-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wtarreau/prandom: random32: add a selftest for the prandom32 code random32: add noise from network and scheduling activity random32: make prandom_u32() output unpredictable		2020-10-25 10:40:08 -07:00
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842
crypto
dim
fonts
kunit
livepatch
lz4
lzo
math
mpi
pldmfw
raid6
reed_solomon
vdso
xz
zlib_deflate
zlib_dfltcc
zlib_inflate
zstd
.gitignore
argv_split.c
ashldi3.c
ashrdi3.c
asn1_decoder.c
assoc_array.c
atomic64.c
atomic64_test.c
audit.c
bcd.c
bch.c
bitfield_kunit.c
bitmap.c
bitrev.c
bootconfig.c
bsearch.c
btree.c
bucket_locks.c
bug.c
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
crc-ccitt.c
crc-itu-t.c
crc-t10dif.c
crc4.c
crc7.c
crc8.c
crc16.c
crc32.c
crc32defs.h
crc32test.c
crc64.c
ctype.c
debug_info.c
debug_locks.c
debugobjects.c
dec_and_lock.c
decompress.c
decompress_bunzip2.c
decompress_inflate.c
decompress_unlz4.c
decompress_unlzma.c
decompress_unlzo.c
decompress_unxz.c
decompress_unzstd.c
devres.c
digsig.c
dump_stack.c
dynamic_debug.c
dynamic_queue_limits.c
earlycpio.c
errname.c
error-inject.c
errseq.c
extable.c
fault-inject-usercopy.c
fault-inject.c
fdt.c
fdt_addresses.c
fdt_empty_tree.c
fdt_ro.c
fdt_rw.c
fdt_strerror.c
fdt_sw.c
fdt_wip.c
find_bit.c
find_bit_benchmark.c
flex_proportions.c
gen_crc32table.c
gen_crc64table.c
genalloc.c
generic-radix-tree.c
glob.c
globtest.c
hexdump.c
hweight.c
idr.c
inflate.c
interval_tree.c
interval_tree_test.c
iomap.c
iomap_copy.c
iommu-helper.c
iov_iter.c
irq_poll.c
irq_regs.c
is_single_threaded.c
kasprintf.c
Kconfig
Kconfig.debug
Kconfig.kasan
Kconfig.kcsan
Kconfig.kgdb
Kconfig.ubsan
kfifo.c
klist.c
kobject.c
kobject_uevent.c
kstrtox.c
kstrtox.h
libcrc32c.c
linear_ranges.c
list-test.c
list_debug.c
list_sort.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
lockref.c
logic_pio.c
lru_cache.c
lshrdi3.c
Makefile
memcat_p.c
memory-notifier-error-inject.c
memregion.c
memweight.c
muldi3.c
net_utils.c
netdev-notifier-error-inject.c
nlattr.c
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-refcount.c
percpu_counter.c
percpu_test.c
plist.c
pm-notifier-error-inject.c
radix-tree.c
random32.c	random32: add a selftest for the prandom32 code	2020-10-24 20:21:57 +02:00
ratelimit.c
rbtree.c
rbtree_test.c
refcount.c
rhashtable.c
sbitmap.c
scatterlist.c	block-5.10-2020-10-24	2020-10-24 12:46:42 -07:00
seq_buf.c
sg_pool.c
sg_split.c
sha1.c
show_mem.c
siphash.c
smp_processor_id.c
sort.c
stackdepot.c
stmp_device.c
string.c
string_helpers.c
strncpy_from_user.c
strnlen_user.c
syscall.c
test-kstrtox.c
test-string_helpers.c
test_bitmap.c
test_bitops.c
test_bits.c
test_blackhole_dev.c
test_bpf.c
test_debug_virtual.c
test_firmware.c
test_fpu.c
test_free_pages.c
test_hash.c
test_hexdump.c
test_hmm.c
test_hmm_uapi.h
test_ida.c
test_kasan.c
test_kasan_module.c
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
test_ubsan.c
test_user_copy.c
test_uuid.c
test_vmalloc.c
test_xarray.c
textsearch.c
timerqueue.c
ts_bm.c
ts_fsm.c
ts_kmp.c
ubsan.c
ubsan.h
ucmpdi2.c
ucs2_string.c
usercopy.c
uuid.c
vsprintf.c
win_minmax.c
xarray.c
xxhash.c