From patchwork Mon Mar 1 16:13:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 389809 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E36CDC43142 for ; Mon, 1 Mar 2021 18:03:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C436B653EB for ; Mon, 1 Mar 2021 18:03:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239211AbhCASDb (ORCPT ); Mon, 1 Mar 2021 13:03:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:52490 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237577AbhCAR4t (ORCPT ); Mon, 1 Mar 2021 12:56:49 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3439C65253; Mon, 1 Mar 2021 17:28:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614619683; bh=IcTdTKUdRz82ut84jVSWQPuXkYg+kRy4McALB7/uNfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a5ZVgaGKDHntvlCeW6C1WHW/fDdh2PdCKpqistL6vOWdYcAWqRreL5+ptNonjNH0o auFWnXl9FGVL9hKsJwogn2MzOHCcOEJRbTaFVg5P0ZBuvnbo2OFWXqFkITKBk6vlQK TSHKX+Pzfou8qBbJ5Cbt52mavCx+9nX5Ar92m87A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ard Biesheuvel , Herbert Xu Subject: [PATCH 5.10 543/663] crypto: aesni - prevent misaligned buffers on the stack Date: Mon, 1 Mar 2021 17:13:11 +0100 Message-Id: <20210301161208.736501888@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161141.760350206@linuxfoundation.org> References: <20210301161141.760350206@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ard Biesheuvel commit a13ed1d15b07a04b1f74b2df61ff7a5e47f45dd8 upstream. The GCM mode driver uses 16 byte aligned buffers on the stack to pass the IV to the asm helpers, but unfortunately, the x86 port does not guarantee that the stack pointer is 16 byte aligned upon entry in the first place. Since the compiler is not aware of this, it will not emit the additional stack realignment sequence that is needed, and so the alignment is not guaranteed to be more than 8 bytes. So instead, allocate some padding on the stack, and realign the IV pointer by hand. Cc: Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- arch/x86/crypto/aesni-intel_glue.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) --- a/arch/x86/crypto/aesni-intel_glue.c +++ b/arch/x86/crypto/aesni-intel_glue.c @@ -686,7 +686,8 @@ static int gcmaes_crypt_by_sg(bool enc, struct crypto_aead *tfm = crypto_aead_reqtfm(req); unsigned long auth_tag_len = crypto_aead_authsize(tfm); const struct aesni_gcm_tfm_s *gcm_tfm = aesni_gcm_tfm; - struct gcm_context_data data AESNI_ALIGN_ATTR; + u8 databuf[sizeof(struct gcm_context_data) + (AESNI_ALIGN - 8)] __aligned(8); + struct gcm_context_data *data = PTR_ALIGN((void *)databuf, AESNI_ALIGN); struct scatter_walk dst_sg_walk = {}; unsigned long left = req->cryptlen; unsigned long len, srclen, dstlen; @@ -735,8 +736,7 @@ static int gcmaes_crypt_by_sg(bool enc, } kernel_fpu_begin(); - gcm_tfm->init(aes_ctx, &data, iv, - hash_subkey, assoc, assoclen); + gcm_tfm->init(aes_ctx, data, iv, hash_subkey, assoc, assoclen); if (req->src != req->dst) { while (left) { src = scatterwalk_map(&src_sg_walk); @@ -746,10 +746,10 @@ static int gcmaes_crypt_by_sg(bool enc, len = min(srclen, dstlen); if (len) { if (enc) - gcm_tfm->enc_update(aes_ctx, &data, + gcm_tfm->enc_update(aes_ctx, data, dst, src, len); else - gcm_tfm->dec_update(aes_ctx, &data, + gcm_tfm->dec_update(aes_ctx, data, dst, src, len); } left -= len; @@ -767,10 +767,10 @@ static int gcmaes_crypt_by_sg(bool enc, len = scatterwalk_clamp(&src_sg_walk, left); if (len) { if (enc) - gcm_tfm->enc_update(aes_ctx, &data, + gcm_tfm->enc_update(aes_ctx, data, src, src, len); else - gcm_tfm->dec_update(aes_ctx, &data, + gcm_tfm->dec_update(aes_ctx, data, src, src, len); } left -= len; @@ -779,7 +779,7 @@ static int gcmaes_crypt_by_sg(bool enc, scatterwalk_done(&src_sg_walk, 1, left); } } - gcm_tfm->finalize(aes_ctx, &data, authTag, auth_tag_len); + gcm_tfm->finalize(aes_ctx, data, authTag, auth_tag_len); kernel_fpu_end(); if (!assocmem) @@ -828,7 +828,8 @@ static int helper_rfc4106_encrypt(struct struct crypto_aead *tfm = crypto_aead_reqtfm(req); struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm); void *aes_ctx = &(ctx->aes_key_expanded); - u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN))); + u8 ivbuf[16 + (AESNI_ALIGN - 8)] __aligned(8); + u8 *iv = PTR_ALIGN(&ivbuf[0], AESNI_ALIGN); unsigned int i; __be32 counter = cpu_to_be32(1); @@ -855,7 +856,8 @@ static int helper_rfc4106_decrypt(struct struct crypto_aead *tfm = crypto_aead_reqtfm(req); struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm); void *aes_ctx = &(ctx->aes_key_expanded); - u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN))); + u8 ivbuf[16 + (AESNI_ALIGN - 8)] __aligned(8); + u8 *iv = PTR_ALIGN(&ivbuf[0], AESNI_ALIGN); unsigned int i; if (unlikely(req->assoclen != 16 && req->assoclen != 20)) @@ -985,7 +987,8 @@ static int generic_gcmaes_encrypt(struct struct crypto_aead *tfm = crypto_aead_reqtfm(req); struct generic_gcmaes_ctx *ctx = generic_gcmaes_ctx_get(tfm); void *aes_ctx = &(ctx->aes_key_expanded); - u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN))); + u8 ivbuf[16 + (AESNI_ALIGN - 8)] __aligned(8); + u8 *iv = PTR_ALIGN(&ivbuf[0], AESNI_ALIGN); __be32 counter = cpu_to_be32(1); memcpy(iv, req->iv, 12); @@ -1001,7 +1004,8 @@ static int generic_gcmaes_decrypt(struct struct crypto_aead *tfm = crypto_aead_reqtfm(req); struct generic_gcmaes_ctx *ctx = generic_gcmaes_ctx_get(tfm); void *aes_ctx = &(ctx->aes_key_expanded); - u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN))); + u8 ivbuf[16 + (AESNI_ALIGN - 8)] __aligned(8); + u8 *iv = PTR_ALIGN(&ivbuf[0], AESNI_ALIGN); memcpy(iv, req->iv, 12); *((__be32 *)(iv+12)) = counter;