afalg: fix coverity 1485661 improper use of negative value

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15635)

1 files changed, 4 insertions, 3 deletions

diff --git a/engines/e_afalg.c b/engines/e_afalg.c
index 93b3b3f02e..f36665acf6 100644
--- a/engines/e_afalg.c
+++ b/engines/e_afalg.c
@@ -544,7 +544,7 @@ static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
                              const unsigned char *iv, int enc)
 {
     int ciphertype;
-    int ret;
+    int ret, len;
     afalg_ctx *actx;
     const char *ciphername;
 
@@ -588,8 +588,9 @@ static int afalg_cipher_init(EVP_CIPHER_CTX *ctx, const unsigned char *key,
     if (ret < 1)
         return 0;
 
-
-    ret = afalg_set_key(actx, key, EVP_CIPHER_CTX_get_key_length(ctx));
+    if ((len = EVP_CIPHER_CTX_get_key_length(ctx)) <= 0)
+        goto err;
+    ret = afalg_set_key(actx, key, len);
     if (ret < 1)
         goto err;