[PATCH v2] crypto/qat: fix docsis segmentation fault

[Rebecca Troy]

Currently if AES or DES algorithms fail for Docsis test suite,
a segmentation fault occurs when cryptodev_qat_autotest is ran.

This is due to a duplicate call of EVP_CIPHER_CTX_free for the
session context. Ctx is freed firstly in the bpi_cipher_ctx_init
function and then again at the end of qat_sym_session_configure_cipher
function.

This commit fixes this bug by removing the first instance
of EVP_CIPHER_CTX_free, leaving just the dedicated function in
the upper level to free the ctx.

Fixes: 98f0608 ("crypto/qat: add symmetric session file")
Cc: fiona.trahe at intel.com
Cc: stable at dpdk.org

Signed-off-by: Rebecca Troy <rebecca.troy at intel.com>
Acked-by: Fan Zhang <roy.fan.zhang at intel.com>

---
V2:
 - Changed the bug fix to set *ctx to NULL after the first
instance of EVP_CIPHER_CTX_free, rather than removing it.
This will ensure NULL checks are met appropriately in further
EVP_CIPHER_CTX_free calls, avoiding segmentation fault without
relying solely on the caller to free the *ctx.
.
---
 drivers/crypto/qat/qat_sym_session.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/qat/qat_sym_session.c b/drivers/crypto/qat/qat_sym_session.c
index e40c042ba9..b30396487e 100644
--- a/drivers/crypto/qat/qat_sym_session.c
+++ b/drivers/crypto/qat/qat_sym_session.c
@@ -136,8 +136,10 @@ bpi_cipher_ctx_init(enum rte_crypto_cipher_algorithm cryptodev_algo,
 	return 0;
 
 ctx_init_err:
-	if (*ctx != NULL)
+	if (*ctx != NULL) {
 		EVP_CIPHER_CTX_free(*ctx);
+		*ctx = NULL;
+	}
 	return ret;
 }
 
-- 
2.25.1