From: Eric Biggers ebiggers@google.com

The ->digest() method of crct10dif-pclmul reads the current CRC value from the shash_desc context. But this value is uninitialized, causing crypto_shash_digest() to compute the wrong result. Fix it.

Probably this wasn't noticed before because lib/crc-t10dif.c only uses crypto_shash_update(), not crypto_shash_digest(). Likewise, crypto_shash_digest() is not yet tested by the crypto self-tests because those only test the ahash API which only uses shash init/update/final.

Fixes: 0b95a7f85718 ("crypto: crct10dif - Glue code to cast accelerated CRCT10DIF assembly as a crypto transform") Cc: stable@vger.kernel.org # v3.11+ Cc: Tim Chen tim.c.chen@linux.intel.com Signed-off-by: Eric Biggers ebiggers@google.com --- arch/x86/crypto/crct10dif-pclmul_glue.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/arch/x86/crypto/crct10dif-pclmul_glue.c b/arch/x86/crypto/crct10dif-pclmul_glue.c index 64f17d2d8b67a..3c81e15b0873f 100644 --- a/arch/x86/crypto/crct10dif-pclmul_glue.c +++ b/arch/x86/crypto/crct10dif-pclmul_glue.c @@ -71,15 +71,14 @@ static int chksum_final(struct shash_desc *desc, u8 *out) return 0; }

-static int __chksum_finup(__u16 *crcp, const u8 *data, unsigned int len, - u8 *out) +static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out) { if (len >= 16 && crypto_simd_usable()) { kernel_fpu_begin(); - *(__u16 *)out = crc_t10dif_pcl(*crcp, data, len); + *(__u16 *)out = crc_t10dif_pcl(crc, data, len); kernel_fpu_end(); } else - *(__u16 *)out = crc_t10dif_generic(*crcp, data, len); + *(__u16 *)out = crc_t10dif_generic(crc, data, len); return 0; }

@@ -88,15 +87,13 @@ static int chksum_finup(struct shash_desc *desc, const u8 *data, { struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);

- return __chksum_finup(&ctx->crc, data, len, out); + return __chksum_finup(ctx->crc, data, len, out); }

static int chksum_digest(struct shash_desc *desc, const u8 *data, unsigned int length, u8 *out) { - struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - - return __chksum_finup(&ctx->crc, data, length, out); + return __chksum_finup(0, data, length, out); }

static struct shash_alg alg = {