From patchwork Fri Jan 15 18:18:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 12023761 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 AD71FC432C3 for ; Fri, 15 Jan 2021 18:20:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FFF1222B3 for ; Fri, 15 Jan 2021 18:20:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388344AbhAOSUX (ORCPT ); Fri, 15 Jan 2021 13:20:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:42920 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388279AbhAOSUN (ORCPT ); Fri, 15 Jan 2021 13:20:13 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id F176023AAA; Fri, 15 Jan 2021 18:19:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1610734773; bh=Jel0jSfxzz6JC5YFbmX2zBvLW5g+Ng3wqiU7Ogpwi0U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nV+PbKlE4fejFkAJT2QUpw8lFuA/9WiIzVOwQWxZ8m42b+BxHOeac7Nv6YlEjicfq 9NSow62EK+Kce5qwM4tuIP2FNmGnI6wXaQpgyE3Oi2QZgObDE4cHU0EwJKw7W+7QI3 juUYfw9Dd7eoWLJIeQpui6nAsYH85pO3czfkCYC/8+ei411Yaq6owCWkqVqFFI5m9S aVfh9Vxwm+x/hpT6nvN2QvoQIcFbjV8dhTFfs7RVUpxYhzHusxOnMS75ZVuA+qNssB DjCldKSxFgNoSAhvqz23SuCDosGmeRCT+VaVBego5uOG/vv9IgcpB8VIPQrt/BO3RZ Mx374CmaajuLg== From: Eric Biggers To: linux-fscrypt@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-api@vger.kernel.org, Theodore Ts'o , Jaegeuk Kim , Victor Hsieh Subject: [PATCH 2/6] fs-verity: don't pass whole descriptor to fsverity_verify_signature() Date: Fri, 15 Jan 2021 10:18:15 -0800 Message-Id: <20210115181819.34732-3-ebiggers@kernel.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210115181819.34732-1-ebiggers@kernel.org> References: <20210115181819.34732-1-ebiggers@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Eric Biggers Now that fsverity_get_descriptor() validates the sig_size field, fsverity_verify_signature() doesn't need to do it. Just change the prototype of fsverity_verify_signature() to take the signature directly rather than take a fsverity_descriptor. Signed-off-by: Eric Biggers Reviewed-by: Jaegeuk Kim Reviewed-by: Amy Parker --- fs/verity/fsverity_private.h | 6 ++---- fs/verity/open.c | 3 ++- fs/verity/signature.c | 20 ++++++-------------- 3 files changed, 10 insertions(+), 19 deletions(-) diff --git a/fs/verity/fsverity_private.h b/fs/verity/fsverity_private.h index 6c9caccc06021..a7920434bae50 100644 --- a/fs/verity/fsverity_private.h +++ b/fs/verity/fsverity_private.h @@ -140,15 +140,13 @@ void __init fsverity_exit_info_cache(void); #ifdef CONFIG_FS_VERITY_BUILTIN_SIGNATURES int fsverity_verify_signature(const struct fsverity_info *vi, - const struct fsverity_descriptor *desc, - size_t desc_size); + const u8 *signature, size_t sig_size); int __init fsverity_init_signature(void); #else /* !CONFIG_FS_VERITY_BUILTIN_SIGNATURES */ static inline int fsverity_verify_signature(const struct fsverity_info *vi, - const struct fsverity_descriptor *desc, - size_t desc_size) + const u8 *signature, size_t sig_size) { return 0; } diff --git a/fs/verity/open.c b/fs/verity/open.c index a987bb785e9b0..60ff8af7219fe 100644 --- a/fs/verity/open.c +++ b/fs/verity/open.c @@ -181,7 +181,8 @@ struct fsverity_info *fsverity_create_info(const struct inode *inode, vi->tree_params.hash_alg->name, vi->tree_params.digest_size, vi->file_digest); - err = fsverity_verify_signature(vi, desc, desc_size); + err = fsverity_verify_signature(vi, desc->signature, + le32_to_cpu(desc->sig_size)); out: if (err) { fsverity_free_info(vi); diff --git a/fs/verity/signature.c b/fs/verity/signature.c index 012468eda2a78..143a530a80088 100644 --- a/fs/verity/signature.c +++ b/fs/verity/signature.c @@ -29,21 +29,19 @@ static struct key *fsverity_keyring; /** * fsverity_verify_signature() - check a verity file's signature * @vi: the file's fsverity_info - * @desc: the file's fsverity_descriptor - * @desc_size: size of @desc + * @signature: the file's built-in signature + * @sig_size: size of signature in bytes, or 0 if no signature * - * If the file's fs-verity descriptor includes a signature of the file digest, - * verify it against the certificates in the fs-verity keyring. + * If the file includes a signature of its fs-verity file digest, verify it + * against the certificates in the fs-verity keyring. * * Return: 0 on success (signature valid or not required); -errno on failure */ int fsverity_verify_signature(const struct fsverity_info *vi, - const struct fsverity_descriptor *desc, - size_t desc_size) + const u8 *signature, size_t sig_size) { const struct inode *inode = vi->inode; const struct fsverity_hash_alg *hash_alg = vi->tree_params.hash_alg; - const u32 sig_size = le32_to_cpu(desc->sig_size); struct fsverity_formatted_digest *d; int err; @@ -56,11 +54,6 @@ int fsverity_verify_signature(const struct fsverity_info *vi, return 0; } - if (sig_size > desc_size - sizeof(*desc)) { - fsverity_err(inode, "Signature overflows verity descriptor"); - return -EBADMSG; - } - d = kzalloc(sizeof(*d) + hash_alg->digest_size, GFP_KERNEL); if (!d) return -ENOMEM; @@ -70,8 +63,7 @@ int fsverity_verify_signature(const struct fsverity_info *vi, memcpy(d->digest, vi->file_digest, hash_alg->digest_size); err = verify_pkcs7_signature(d, sizeof(*d) + hash_alg->digest_size, - desc->signature, sig_size, - fsverity_keyring, + signature, sig_size, fsverity_keyring, VERIFYING_UNSPECIFIED_SIGNATURE, NULL, NULL); kfree(d);