From: Eric Biggers <ebiggers@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx> # v3.11+
Cc: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
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 = {
--
2.21.0
