modes: fix coverity 1449851: overlapping memory copy

Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14584)

diff --git a/crypto/modes/cbc128.c b/crypto/modes/cbc128.c
index df0ab244f831e3f2772c5aa65ffab3ed0ee2395d..9ac9299f65880496cd77c4f377bb7802c3324f76 100644 (file)
--- a/crypto/modes/cbc128.c
+++ b/crypto/modes/cbc128.c
@@ -114,7 +114,8 @@ void CRYPTO_cbc128_decrypt(const unsigned char *in, unsigned char *out,
                 out += 16;
             }
         }
-        memcpy(ivec, iv, 16);
+        if (ivec != iv)
+            memcpy(ivec, iv, 16);
     } else {
         if (STRICT_ALIGNMENT &&
             ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) {