From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751521AbdKVTwN (ORCPT ); Wed, 22 Nov 2017 14:52:13 -0500 Received: from mail-it0-f66.google.com ([209.85.214.66]:42477 "EHLO mail-it0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751249AbdKVTwJ (ORCPT ); Wed, 22 Nov 2017 14:52:09 -0500 X-Google-Smtp-Source: AGs4zMZzUQSmZC6akywMBBb95QDKcaMTNGasiccOdgAWo9sNQMazr7JEiAf82ldu46yJcX0MgpNNEg== From: Eric Biggers To: linux-crypto@vger.kernel.org, Herbert Xu Cc: "Theodore Ts'o" , "Jason A . Donenfeld" , Martin Willi , Ard Biesheuvel , linux-kernel@vger.kernel.org, Eric Biggers Subject: [PATCH 1/5] crypto: chacha20 - Fix unaligned access when loading constants Date: Wed, 22 Nov 2017 11:51:35 -0800 Message-Id: <20171122195139.121269-2-ebiggers3@gmail.com> X-Mailer: git-send-email 2.15.0.448.gf294e3d99a-goog In-Reply-To: <20171122195139.121269-1-ebiggers3@gmail.com> References: <20171122195139.121269-1-ebiggers3@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Biggers The four 32-bit constants for the initial state of ChaCha20 were loaded from a char array which is not guaranteed to have the needed alignment. Fix it by just assigning the constants directly instead. Signed-off-by: Eric Biggers --- crypto/chacha20_generic.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/crypto/chacha20_generic.c b/crypto/chacha20_generic.c index 4a45fa4890c0..ec84e7837aac 100644 --- a/crypto/chacha20_generic.c +++ b/crypto/chacha20_generic.c @@ -41,12 +41,10 @@ static void chacha20_docrypt(u32 *state, u8 *dst, const u8 *src, void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv) { - static const char constant[16] = "expand 32-byte k"; - - state[0] = le32_to_cpuvp(constant + 0); - state[1] = le32_to_cpuvp(constant + 4); - state[2] = le32_to_cpuvp(constant + 8); - state[3] = le32_to_cpuvp(constant + 12); + state[0] = 0x61707865; /* "expa" */ + state[1] = 0x3320646e; /* "nd 3" */ + state[2] = 0x79622d32; /* "2-by" */ + state[3] = 0x6b206574; /* "te k" */ state[4] = ctx->key[0]; state[5] = ctx->key[1]; state[6] = ctx->key[2]; -- 2.15.0.448.gf294e3d99a-goog