Fix some possible memory leaks in EVP_CipherInit_ex

An EVP_CONTEXT with zero cipher but non-zero engine,
and/or cipher_data is possible if an error happens
in EVP_CTRL_INIT or in EVP_CTRL_COPY, the error handling
will just clear the cipher in that case.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/16756)

diff --git a/crypto/evp/evp_enc.c b/crypto/evp/evp_enc.c
index e3c165d48e082dc4c46f72fd1296de0494720040..d835968f253ce24c93e2c5af9d9c911f29dae8da 100644 (file)
--- a/crypto/evp/evp_enc.c
+++ b/crypto/evp/evp_enc.c
@@ -85,7 +85,11 @@ int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
          * previous check attempted to avoid this if the same ENGINE and
          * EVP_CIPHER could be used).
          */
-        if (ctx->cipher) {
+        if (ctx->cipher
+#ifndef OPENSSL_NO_ENGINE
+                || ctx->engine
+#endif
+                || ctx->cipher_data) {
             unsigned long flags = ctx->flags;
             EVP_CIPHER_CTX_reset(ctx);
             /* Restore encrypt and flags */
@@ -105,11 +109,7 @@ int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
             /* There's an ENGINE for this job ... (apparently) */
             const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);
             if (!c) {
-                /*
-                 * One positive side-effect of US's export control history,
-                 * is that we should at least be able to avoid using US
-                 * misspellings of "initialisation"?
-                 */
+                ENGINE_finish(impl);
                 EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);
                 return 0;
             }