From 43ea178b120ba626c10c6149e3d37fde2cfcb2d4 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 31 Mar 2019 13:04:13 -0700 Subject: [PATCH] crypto: x86/crct10dif-pcl - fix use via crypto_shash_digest() commit dec3d0b1071a0f3194e66a83d26ecf4aa8c5910e upstream. 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: # v3.11+ Cc: Tim Chen Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- 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 cd4df9322501..7bbfe7d35da7 100644 --- a/arch/x86/crypto/crct10dif-pclmul_glue.c +++ b/arch/x86/crypto/crct10dif-pclmul_glue.c @@ -76,15 +76,14 @@ 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 (irq_fpu_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; } @@ -93,15 +92,13 @@ 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 = { -- 2.20.1