crypto: ccree - dec auth tag size from cryptlen map

Remove the auth tag size from cryptlen before mapping the destination
in out-of-place AEAD decryption thus resolving a crash with
extended testmgr tests.
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: stable@vger.kernel.org # v4.19+
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/ccree/cc_buffer_mgr.c

@@ -894,8 +894,12 @@ static int cc_aead_chain_data(struct cc_drvdata *drvdata,
 
 	if (req->src != req->dst) {
 		size_for_map = areq_ctx->assoclen + req->cryptlen;
-		size_for_map += (direct == DRV_CRYPTO_DIRECTION_ENCRYPT) ?
-				authsize : 0;
+
+		if (direct == DRV_CRYPTO_DIRECTION_ENCRYPT)
+			size_for_map += authsize;
+		else
+			size_for_map -= authsize;
+
 		if (is_gcm4543)
 			size_for_map += crypto_aead_ivsize(tfm);