Hi.
I checked how it works on QAT hardware, and it does no harm. All unit tests
still pass.
Verified on two QAT-enabled machines.
The question is: should this patch be simplified to just add a call to memset
(to zero the digest variable while still keeping it on the stack) at the
function begin? And that will be a faster solution in run-time (using the
variable on the stack instead of calloc that uses the heap).
Adam
> -----Original Message-----
> From: dev <dev-boun...@dpdk.org> On Behalf Of Feifei Wang
> Sent: Monday, 17 May, 2021 11:07
> To: Griffin, John <john.grif...@intel.com>; Trahe, Fiona
> <fiona.tr...@intel.com>; Jain, Deepak K <deepak.k.j...@intel.com>; Jerin
> Jacob <jerin.ja...@caviumnetworks.com>; Herbert Guan
> <herbert.g...@arm.com>
> Cc: dev@dpdk.org; david.march...@redhat.com; n...@arm.com; Feifei
> Wang <feifei.wa...@arm.com>; sta...@dpdk.org; Ruifeng Wang
> <ruifeng.w...@arm.com>
> Subject: [dpdk-dev] [PATCH v3] crypto/qat: fix uninitilized compiler warning
>
> In Arm platform, when "RTE_ARCH_ARM64_MEMCPY" is set as true,
> compiler will report variable uninitilized warning:
>
> ../drivers/crypto/qat/qat_sym_session.c:
> In function ‘partial_hash_compute’:
> ../lib/eal/include/generic/rte_byteorder.h:241:24: warning:
> ‘<U35a0>’ may be used uninitialized in this function
> [-Wmaybe-uninitialized]
> 241 | #define rte_bswap32(x) __builtin_bswap32(x)
> ...
>
> This is because "digest" will be initialized by "rte_memcpy" function rather
> than "memcpy" if "RTE_ARCH_ARM64_MEMCPY" is set as true. However,
> compiler cannot know it is initialized by the function.
>
> To fix this, use "calloc" to initialize "digest".
>
> Fixes: cd7fc8a84b48 ("eal/arm64: optimize memcpy")
> Cc: sta...@dpdk.org
>
> Signed-off-by: Feifei Wang <feifei.wa...@arm.com>
> Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com>
> ---
> v2: add check and free for memory dynamic allocation (David Marchand)
> v3: fix compiler error
>
> drivers/crypto/qat/qat_sym_session.c | 27 ++++++++++++++++++---------
> 1 file changed, 18 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/crypto/qat/qat_sym_session.c
> b/drivers/crypto/qat/qat_sym_session.c
> index 231b1640da..105a10957a 100644
> --- a/drivers/crypto/qat/qat_sym_session.c
> +++ b/drivers/crypto/qat/qat_sym_session.c
> @@ -1190,8 +1190,7 @@ static int partial_hash_compute(enum
> icp_qat_hw_auth_algo hash_alg,
> uint8_t *data_out)
> {
> int digest_size;
> - uint8_t digest[qat_hash_get_digest_size(
> - ICP_QAT_HW_AUTH_ALGO_DELIMITER)];
> + uint8_t *digest;
> uint32_t *hash_state_out_be32;
> uint64_t *hash_state_out_be64;
> int i;
> @@ -1200,55 +1199,65 @@ static int partial_hash_compute(enum
> icp_qat_hw_auth_algo hash_alg,
> if (digest_size <= 0)
> return -EFAULT;
>
> + digest = calloc(qat_hash_get_digest_size(
> + ICP_QAT_HW_AUTH_ALGO_DELIMITER),
> sizeof(uint8_t));
> + if (!digest)
> + return -ENOMEM;
> +
> hash_state_out_be32 = (uint32_t *)data_out;
> hash_state_out_be64 = (uint64_t *)data_out;
>
> switch (hash_alg) {
> case ICP_QAT_HW_AUTH_ALGO_SHA1:
> if (partial_hash_sha1(data_in, digest))
> - return -EFAULT;
> + goto fail;
> for (i = 0; i < digest_size >> 2; i++, hash_state_out_be32++)
> *hash_state_out_be32 =
> rte_bswap32(*(((uint32_t *)digest)+i));
> break;
> case ICP_QAT_HW_AUTH_ALGO_SHA224:
> if (partial_hash_sha224(data_in, digest))
> - return -EFAULT;
> + goto fail;
> for (i = 0; i < digest_size >> 2; i++, hash_state_out_be32++)
> *hash_state_out_be32 =
> rte_bswap32(*(((uint32_t *)digest)+i));
> break;
> case ICP_QAT_HW_AUTH_ALGO_SHA256:
> if (partial_hash_sha256(data_in, digest))
> - return -EFAULT;
> + goto fail;
> for (i = 0; i < digest_size >> 2; i++, hash_state_out_be32++)
> *hash_state_out_be32 =
> rte_bswap32(*(((uint32_t *)digest)+i));
> break;
> case ICP_QAT_HW_AUTH_ALGO_SHA384:
> if (partial_hash_sha384(data_in, digest))
> - return -EFAULT;
> + goto fail;
> for (i = 0; i < digest_size >> 3; i++, hash_state_out_be64++)
> *hash_state_out_be64 =
> rte_bswap64(*(((uint64_t *)digest)+i));
> break;
> case ICP_QAT_HW_AUTH_ALGO_SHA512:
> if (partial_hash_sha512(data_in, digest))
> - return -EFAULT;
> + goto fail;
> for (i = 0; i < digest_size >> 3; i++, hash_state_out_be64++)
> *hash_state_out_be64 =
> rte_bswap64(*(((uint64_t *)digest)+i));
> break;
> case ICP_QAT_HW_AUTH_ALGO_MD5:
> if (partial_hash_md5(data_in, data_out))
> - return -EFAULT;
> + goto fail;
> break;
> default:
> QAT_LOG(ERR, "invalid hash alg %u", hash_alg);
> - return -EFAULT;
> + goto fail;
> }
>
> + free(digest);
> return 0;
> +
> +fail:
> + free(digest);
> + return -EFAULT;
> }
> #define HMAC_IPAD_VALUE 0x36
> #define HMAC_OPAD_VALUE 0x5c
> --
> 2.25.1
