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author | George Spelvin <lkml@sdf.org> | 2019-03-21 10:42:22 +0000 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-04-20 22:03:11 +1000 |
commit | 80d04b7fabe161a23d143b3bfcfca1b002c23da1 (patch) | |
tree | c6e44382032d68519aa3975307fb0ece3c23d4b0 /arch/powerpc/crypto | |
parent | 6917735e8f905da1f62ccdf62830b185524835c7 (diff) | |
download | linux-stable-80d04b7fabe161a23d143b3bfcfca1b002c23da1.tar.gz linux-stable-80d04b7fabe161a23d143b3bfcfca1b002c23da1.tar.bz2 linux-stable-80d04b7fabe161a23d143b3bfcfca1b002c23da1.zip |
powerpc/crypto: Use cheaper random numbers for crc-vpmsum self-test
This code was filling a 64K buffer from /dev/urandom in order to
compute a CRC over (on average half of) it by two different methods,
comparing the CRCs, and repeating.
This is not a remotely security-critical application, so use the far
faster and cheaper prandom_u32() generator.
And, while we're at it, only fill as much of the buffer as we plan to use.
Signed-off-by: George Spelvin <lkml@sdf.org>
Acked-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/crypto')
-rw-r--r-- | arch/powerpc/crypto/crc-vpmsum_test.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/arch/powerpc/crypto/crc-vpmsum_test.c b/arch/powerpc/crypto/crc-vpmsum_test.c index 0153a9c6f4af..98ea4f4d3dde 100644 --- a/arch/powerpc/crypto/crc-vpmsum_test.c +++ b/arch/powerpc/crypto/crc-vpmsum_test.c @@ -78,16 +78,12 @@ static int __init crc_test_init(void) pr_info("crc-vpmsum_test begins, %lu iterations\n", iterations); for (i=0; i<iterations; i++) { - size_t len, offset; + size_t offset = prandom_u32_max(16); + size_t len = prandom_u32_max(MAX_CRC_LENGTH); - get_random_bytes(data, MAX_CRC_LENGTH); - get_random_bytes(&len, sizeof(len)); - get_random_bytes(&offset, sizeof(offset)); - - len %= MAX_CRC_LENGTH; - offset &= 15; if (len <= offset) continue; + prandom_bytes(data, len); len -= offset; crypto_shash_update(crct10dif_shash, data+offset, len); |