commit 678cce4019d746da6c680c48ba9e6d417803e127 upstream. The x86_64 implementation of Poly1305 produces the wrong result on some inputs because poly1305_4block_avx2() incorrectly assumes that when partially reducing the accumulator, the bits carried from limb 'd4' to limb 'h0' fit in a 32-bit integer. This is true for poly1305-generic which processes only one block at a time. However, it's not true for the AVX2 implementation, which processes 4 blocks at a time and therefore can produce intermediate limbs about 4x larger. Fix it by making the relevant calculations use 64-bit arithmetic rather than 32-bit. Note that most of the carries already used 64-bit arithmetic, but the d4 -> h0 carry was different for some reason. To be safe I also made the same change to the corresponding SSE2 code, though that only operates on 1 or 2 blocks at a time. I don't think it's really needed for poly1305_block_sse2(), but it doesn't hurt because it's already x86_64 code. It *might* be needed for poly1305_2block_sse2(), but overflows aren't easy to reproduce there. This bug was originally detected by my patches that improve testmgr to fuzz algorithms against their generic implementation. But also add a test vector which reproduces it directly (in the AVX2 case). Fixes: |
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.. | ||
asymmetric_keys | ||
async_tx | ||
.gitignore | ||
842.c | ||
ablk_helper.c | ||
ablkcipher.c | ||
aead.c | ||
aes_generic.c | ||
af_alg.c | ||
ahash.c | ||
akcipher.c | ||
algapi.c | ||
algboss.c | ||
algif_aead.c | ||
algif_hash.c | ||
algif_rng.c | ||
algif_skcipher.c | ||
ansi_cprng.c | ||
anubis.c | ||
api.c | ||
arc4.c | ||
authenc.c | ||
authencesn.c | ||
blkcipher.c | ||
blowfish_common.c | ||
blowfish_generic.c | ||
camellia_generic.c | ||
cast5_generic.c | ||
cast6_generic.c | ||
cast_common.c | ||
cbc.c | ||
ccm.c | ||
chacha20_generic.c | ||
chacha20poly1305.c | ||
chainiv.c | ||
cipher.c | ||
cmac.c | ||
compress.c | ||
crc32.c | ||
crc32c_generic.c | ||
crct10dif_common.c | ||
crct10dif_generic.c | ||
cryptd.c | ||
crypto_null.c | ||
crypto_user.c | ||
crypto_wq.c | ||
ctr.c | ||
cts.c | ||
deflate.c | ||
des_generic.c | ||
drbg.c | ||
ecb.c | ||
echainiv.c | ||
eseqiv.c | ||
fcrypt.c | ||
fips.c | ||
gcm.c | ||
gf128mul.c | ||
ghash-generic.c | ||
hash_info.c | ||
hmac.c | ||
internal.h | ||
jitterentropy-kcapi.c | ||
jitterentropy.c | ||
Kconfig | ||
keywrap.c | ||
khazad.c | ||
lrw.c | ||
lz4.c | ||
lz4hc.c | ||
lzo.c | ||
Makefile | ||
mcryptd.c | ||
md4.c | ||
md5.c | ||
memneq.c | ||
michael_mic.c | ||
pcbc.c | ||
pcompress.c | ||
pcrypt.c | ||
poly1305_generic.c | ||
proc.c | ||
ripemd.h | ||
rmd128.c | ||
rmd160.c | ||
rmd256.c | ||
rmd320.c | ||
rng.c | ||
rsa.c | ||
rsa_helper.c | ||
rsaprivkey.asn1 | ||
rsapubkey.asn1 | ||
salsa20_generic.c | ||
scatterwalk.c | ||
seed.c | ||
seqiv.c | ||
serpent_generic.c | ||
sha1_generic.c | ||
sha256_generic.c | ||
sha512_generic.c | ||
shash.c | ||
skcipher.c | ||
tcrypt.c | ||
tcrypt.h | ||
tea.c | ||
testmgr.c | ||
testmgr.h | ||
tgr192.c | ||
twofish_common.c | ||
twofish_generic.c | ||
vmac.c | ||
wp512.c | ||
xcbc.c | ||
xor.c | ||
xts.c | ||
zlib.c |