2017-03-03 06:57:38

by Daniel Axtens

Subject: [PATCH] crypto: powerpc - Fix initialisation of crc32c context

Turning on crypto self-tests on a POWER8 shows:

alg: hash: Test 1 failed for crc32c-vpmsum
00000000: ff ff ff ff

Comparing the code with the Intel CRC32c implementation on which
ours is based shows that we are doing an init with 0, not ~0
as CRC32c requires.

This probably wasn't caught because btrfs does its own weird
open-coded initialisation.

Initialise our internal context to ~0 on init.

This makes the self-tests pass, and btrfs continues to work.

Fixes: 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
Cc: Anton Blanchard <[email protected]>
Cc: [email protected]
Signed-off-by: Daniel Axtens <[email protected]>
---
arch/powerpc/crypto/crc32c-vpmsum_glue.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
index 9fa046d56eba..411994551afc 100644
--- a/arch/powerpc/crypto/crc32c-vpmsum_glue.c
+++ b/arch/powerpc/crypto/crc32c-vpmsum_glue.c
@@ -52,7 +52,7 @@ static int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm)
{
u32 *key = crypto_tfm_ctx(tfm);

- *key = 0;
+ *key = ~0;

return 0;
}
--
2.9.3

2017-03-06 02:48:57

by Anton Blanchard

Subject: Re: [PATCH] crypto: powerpc - Fix initialisation of crc32c context

Hi Daniel,

> Turning on crypto self-tests on a POWER8 shows:
>
> alg: hash: Test 1 failed for crc32c-vpmsum
> 00000000: ff ff ff ff
>
> Comparing the code with the Intel CRC32c implementation on which
> ours is based shows that we are doing an init with 0, not ~0
> as CRC32c requires.
>
> This probably wasn't caught because btrfs does its own weird
> open-coded initialisation.
>
> Initialise our internal context to ~0 on init.
>
> This makes the self-tests pass, and btrfs continues to work.

Thanks! Not sure how I screwed that up.

Acked-by: Anton Blanchard <[email protected]>

> Fixes: 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
> Cc: Anton Blanchard <[email protected]>
> Cc: [email protected]
> Signed-off-by: Daniel Axtens <[email protected]>
> ---
> arch/powerpc/crypto/crc32c-vpmsum_glue.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/crypto/crc32c-vpmsum_glue.c
> b/arch/powerpc/crypto/crc32c-vpmsum_glue.c index
> 9fa046d56eba..411994551afc 100644 ---
> a/arch/powerpc/crypto/crc32c-vpmsum_glue.c +++
> b/arch/powerpc/crypto/crc32c-vpmsum_glue.c @@ -52,7 +52,7 @@ static
> int crc32c_vpmsum_cra_init(struct crypto_tfm *tfm) {
> u32 *key = crypto_tfm_ctx(tfm);
>
> - *key = 0;
> + *key = ~0;
>
> return 0;
> }

2017-03-06 04:43:36

by Michael Ellerman

Subject: Re: [PATCH] crypto: powerpc - Fix initialisation of crc32c context

Daniel Axtens <[email protected]> writes:

> Turning on crypto self-tests on a POWER8 shows:
>
> alg: hash: Test 1 failed for crc32c-vpmsum
> 00000000: ff ff ff ff
>
> Comparing the code with the Intel CRC32c implementation on which
> ours is based shows that we are doing an init with 0, not ~0
> as CRC32c requires.
>
> This probably wasn't caught because btrfs does its own weird
> open-coded initialisation.
>
> Initialise our internal context to ~0 on init.
>
> This makes the self-tests pass, and btrfs continues to work.
>
> Fixes: 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
> Cc: Anton Blanchard <[email protected]>
> Cc: [email protected]
> Signed-off-by: Daniel Axtens <[email protected]>
> ---
> arch/powerpc/crypto/crc32c-vpmsum_glue.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

This driver was originally merged via the crypto tree, so I'll assume
Herbert will pick up the fix. If he hasn't in a few days I'll take it.

cheers

2017-03-08 08:47:10

by Herbert Xu

Subject: Re: [PATCH] crypto: powerpc - Fix initialisation of crc32c context

Daniel Axtens <[email protected]> wrote:
> Turning on crypto self-tests on a POWER8 shows:
>
> alg: hash: Test 1 failed for crc32c-vpmsum
> 00000000: ff ff ff ff
>
> Comparing the code with the Intel CRC32c implementation on which
> ours is based shows that we are doing an init with 0, not ~0
> as CRC32c requires.
>
> This probably wasn't caught because btrfs does its own weird
> open-coded initialisation.
>
> Initialise our internal context to ~0 on init.
>
> This makes the self-tests pass, and btrfs continues to work.
>
> Fixes: 6dd7a82cc54e ("crypto: powerpc - Add POWER8 optimised crc32c")
> Cc: Anton Blanchard <[email protected]>
> Cc: [email protected]
> Signed-off-by: Daniel Axtens <[email protected]>

Patch applied. Thanks.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt